WO2012089607A1 - Novel compounds with a 3a-azabicyclo [4.1.0] heptane core acting on orexin receptors - Google Patents

Abstract

This invention relates to azabicyclo[4.1.0]hept-4-yl derivatives and their use as pharmaceuticals.

Description

NOVEL COMPOUNDS WITH A 3A-AZABICYCLO [4.1.0] HEPTANE CORE ACTING ON OREXIN RECEPTORS

This invention relates to azabicyclo[4.1.0]hept-4-yl derivatives and their use as pharmaceuticals.

Many medically significant biological processes are mediated by proteins participating in signal transduction pathways that involve G-proteins and/or second messengers.

Polypeptides and polynucleotides encoding the human 7-transmembrane G-protein coupled neuropeptide receptor, orexin-1 (HFGAN72), have been identified and are disclosed in EP875565, EP875566 and WO 96/34877. Polypeptides and polynucleotides encoding a second human orexin receptor, orexin-2 (HFGANP), have been identified and are disclosed in EP893498.

Polypeptides and polynucleotides encoding polypeptides which are ligands for the orexin-1 receptor, e.g. orexin-A (Lig72A) are disclosed in EP849361.

The orexin ligand and receptor system has been well characterised since its discovery (see for example Sakurai, T. et al (1998) Cell, 92 pp 573 to 585; Smart et al (1999) British Journal of Pharmacology 128 pp 1 to 3; Willie et al (2001) Ann. Rev.

Neurosciences 24 pp 429 to 458; Sakurai (2007) Nature Reviews Neuroscience 8 pp 171 to 181; Ohno and Sakurai (2008) Front. Neuroendocrinology 29 pp 70 to 87). From these studies it has become clear that orexins and orexin receptors play a number of important physiological roles in mammals and open up the possibility of the development of new therapeutic treatments for a variety of diseases and disorders as described hereinbelow.

Experiments have shown that central administration of the ligand orexin-A stimulated food intake in freely-feeding rats during a 4 hour time period. This increase was approximately four-fold over control rats receiving vehicle. These data suggest that orexin- A may be an endogenous regulator of appetite (Sakurai, T. et al (1998) Cell, 92 pp 573 to 585; Peyron et al (1998) J. Neurosciences 18 pp 9996 to 10015; Willie et al (2001) Ann. Rev. Neurosciences 24 pp 429 to 458). Therefore, antagonists of the orexin-A receptor(s) may be useful in the treatment of obesity and diabetes. In support of this it has been shown that orexin receptor antagonist SB334867 potently reduced hedonic eating in rats (White et al (2005) Peptides 26 pp 2231 to 2238) and also attenuated high-fat pellet self- administration in rats (Nair et al (2008) British Journal of Pharmacology, published online 28 January 2008).

The search for new therapies to treat obesity and other eating disorders is an important challenge. According to WHO definitions a mean of 35% of subjects in 39 studies were overweight and a further 22% clinically obese in westernised societies. It has been estimated that 5.7% of all healthcare costs in the USA are a consequence of obesity. About 85%) of Type 2 diabetics are obese. Diet and exercise are of value in all diabetics. The incidence of diagnosed diabetes in westernised countries is typically 5% and there are estimated to be an equal number undiagnosed. The incidence of obesity and Type 2 diabetes is rising, demonstrating the inadequacy of current treatments which may be either ineffective or have toxicity risks including cardiovascular effects. Treatment of diabetes with sulfonylureas or insulin can cause hypoglycaemia, whilst metformin causes GI side- effects. No drug treatment for Type 2 diabetes has been shown to reduce the long-term complications of the disease. Insulin sensitisers will be useful for many diabetics, however they do not have an anti-obesity effect.

As well as having a role in food intake, the orexin system is also involved in sleep and wakefulness. Rat sleep/EEG studies have shown that central administration of orexin- A, an agonist of the orexin receptors, causes a dose-related increase in arousal, largely at the expense of a reduction in paradoxical sleep and slow wave sleep 2, when administered at the onset of the normal sleep period (Hagan et al (1999) Proc.Natl.Acad.Sci. 96 pp 10911 to 10916). The role of the orexin system in sleep and wakefulness is now well established (Sakurai (2007) Nature Reviews Neuroscience 8 pp 171 to 181 ; Ohno and Sakurai (2008) Front. Neuroendocrinology 29 pp 70 to 87; Chemelli et al (1999) Cell 98 pp 437 to 451; Lee et al (2005) J. Neuroscience 25 pp 6716 to 6720; Piper et al (2000) European J

Neuroscience 12 pp 726-730 and Smart and Jerman (2002) Pharmacology and Therapeutics 94 pp 51 to 61). Antagonists of the orexin receptors may therefore be useful in the treatment of sleep disorders including insomnia. Studies with orexin receptor antagonists, for example SB334867, in rats (see for example Smith et al (2003) Neuroscience Letters 341 pp 256 to 258) and more recently dogs and humans (Brisbare-Roch et al (2007) Nature Medicine 13(2) pp 150 to 155) further support this.

In addition, recent studies have suggested a role for orexin antagonists in the treatment of motivational disorders, such as disorders related to reward seeking behaviours for example drug addiction and substance abuse (Borgland et al (2006) Neuron 49(4) pp 589-601; Boutrel et al (2005) Proc.Natl.Acad.Sci. 102(52) pp 19168 to 19173; Harris et al (2005) Nature 437 pp 556 to 559).

International Patent Applications WO99/09024, W099/58533, WO00/47577 and WO00/47580 disclose phenyl urea derivatives and WO00/47576 discloses quinolinyl cinnamide derivatives as orexin receptor antagonists. WO05/118548 discloses substituted 1,2,3,4-tetrahydroisoquinoline derivatives as orexin antagonists.

WO01/96302, WO02/44172, WO02/89800, WO03/002559, WO03/002561, WO03/032991, WO03/037847, WO03/041711, WO08/038251, WO09/003993,

WO09/003997 and WO09/124956 all disclose cyclic amine derivatives.

WO08/038251 discloses 3-aza-bicyclo[3.1.0]hexane derivatives as orexin antagonists. We have now found that certain azabicyclo[4.1.0]hept-4-yl derivatives have beneficial properties including, for example, high potency, good brain penetration and good bioavailability. Such properties make these azabicyclo[4.1.0]hept-4-yl derivatives very attractive as potential pharmaceutical agents which may be useful in the prevention or treatment of obesity, including obesity observed in Type 2 (non-insulin-dependent) diabetes patients, sleep disorders, anxiety, depression, schizophrenia, drug dependency or compulsive behaviour. Additionally these compounds may be useful in the treatment of stroke, particularly ischemic or haemorrhagic stroke, and/or blocking the emetic response, i.e. useful in the treatment of nausea and vomiting.

Accordingly the present invention provides a compound of formula (I)

(I)

wherein:

Het is a heteroaryl group selected from pyridinyl, pyrimidinyl, pyridazinyl, pyrazinyl, triazinyl, thiazolyl or thiadiazolyl, said heteroaryl group being optionally substituted with 1, 2 or 3 substituents independently selected from the group consisting of: Ci_-4alkyl, halo, Ci. ₄alkoxy, haloCi_-4alkyl, haloCi_-4alkoxy and cyano;

X is C or N;

Y is C orN;

Ri is Ci_-4alkyl, halo, Ci- alkoxy, haloCi_-4alkyl, haloCi- alkoxy, cyano, C_1-4alkylS0₂, C_3-8 cycloalkylS0₂, C_3-8cycloalkylCH₂S0₂, phenyl or a 5 or 6 membered heterocyclyl group containing 1, 2 or 3 atoms selected from N, O or S, which phenyl or heterocyclyl group is optionally substituted with Ci_-4alkyl, halo, Ci_-4alkoxy, haloCi_-4alkyl, haloCi_-4alkoxy or cyano;

R₂ is C_1-4alkyl, halo, C_1-4alkoxy, haloC_1-4alkyl, haloC_1-4alkoxy, cyano, phenyl or a 5 or 6 membered heterocyclyl group containing 1, 2 or 3 atoms selected from N, O or S, which phenyl or heterocyclyl group is optionally substituted with Ci_-4alkyl, halo, Ci_-4alkoxy, haloCi- alkyl, haloCi- alkoxy or cyano;

R₃ is

or cyano;

m is 0 or l; and

n is 0 or 1;

or a pharmaceutically acceptable salt thereof.

In one embodiment the stereogenic centres of the compounds of formula (I) are in a cis (IS,4R,6S)- configuration.

In one embodiment the stereogenic centres of the compounds of formula (I) are in a trans (IR,4R,6R)- configuration.

In one embodiment Het is pyridinyl.

In one embodiment Het is pyrimidinyl.

In one embodiment Het is pyridazinyl.

In one embodiment Het is pyrazinyl.

In one embodiment Het is triazinyl.

In one embodiment Het is thiazolyl.

In one embodiment Het is thiadiazolyl.

In one embodiment Het is substituted with trifluoromethyl.

In one embodiment X and Y are both carbon.

In one embodiment X and Y are both nitrogen.

In one embodiment X is nitrogen and Y is carbon. In one embodiment X is carbon and Y is nitrogen.

In one embodiment Ri is triazolyl.

In one embodiment Ri is pyrazolyl.

In one embodiment Ri is pyrimidinyl.

In one embodiment m is 1 and n is 0.

In one embodiment m is 1, n is 0 and R₂ is methyl.

In one embodiment the invention provides the compound of formula (I) selected from the group consisting of:

(lR,4R,6R)-3-{[6-methyl-3-(2-pyrimidinyl)-2-pyridinyl]carbonyl}-4-{2-[5- (trifluoromethyl)-2-pyridinyl] ethyl } -3 -azabicyclo[4.1. OJheptane;

(lR,4R,6R)-3-{[6-methyl-3-(2-pyrimidinyl)-2-pyridinyl]carbonyl}-4-{2-[4- (trifluoromethyl)-2-pyridinyl]ethyl}-3-azabicyclo[4.1.0]heptanes;

(lR,4R,6R)-3-{[5-methyl-2-(2-pyrimidinyl)phenyl]carbonyl}-4-{2-[5-(trifluoromethyl)-2- pyridinyl] ethyl } -3 -azabicyclo[4.1.OJheptane;

(lR,4R,6R)-3-{[6-methyl-3-(2-pyrimidinyl)-2-pyridinyl]carbonyl}-4-{2-[4-

(trifluorom ethyl)- 1 ,3 -thiazol-2-yl]ethyl } -3-azabicyclo[4.1.OJheptane;

(lR,4R,6R)-3-{[6-methyl-3-(2-pyrimidinyl)-2-pyridinyl]carbonyl}-4-{2-[2-

(trifluoromethyl)-4-pyrimidinyl]ethyl}-3-azabicyclo[4.1. OJheptane;

(lR,4R,6R)-3-{[6-methyl-3-(2-pyrimidinyl)-2-pyridinyl]carbonyl}-4-{2-[6-methyl-4-

(trifluoromethyl)-3-pyridazinyl]ethyl}-3-azabicyclo[4.1. OJheptane;

(lR,4R,6R)-3-{[6-methyl-3-(2-pyrimidinyl)-2-pyridinyl]carbonyl}-4-{2-[6-methyl-4-

(trifluoromethyl)-2-pyridinyl]ethyl}-3-azabicyclo[4.1. OJheptane;

(lR,4R,6R)-3-{[6-methyl-3-(2H-l,2,3-triazol-2-yl)-2-pyridinyl]carbonyl}-4-{2-[5-

(trifluorom ethyl)- 1 ,3 ,4-thiadiazol-2-yl]ethyl } -3-azabicyclo[4.1.OJheptane;

(lR,4R,6R)-3-{[6-methyl-3-(2H-l,2,3-triazol-2-yl)-2-pyridinyl]carbonyl}-4-{2-[5-

(trifluoromethyl)-2-pyridinyl]ethyl}-3-azabicyclo[4.1.0]heptanes;

6,6'-dimethyl-2'-[((lR,4R,6R)-4-{2-[5-(trifluoromethyl)-2-pyridinyl]ethyl}-3- azabicyclo[4.1.0]hept-3-yl)carbonyl]-2,3'-bipyridine;

(lR,4R,6R)-3-{[6-methyl-3-(2-pyrimidinyl)-2-pyridinyl]carbonyl}-4-{2-[3-

(trifluoromethyl)-2-pyridinyl]ethyl}-3-azabicyclo[4.1.0]heptanes;

(lR,4R,6R)-3-{[6-methyl-3-(2H-l,2,3-triazol-2-yl)-2-pyridinyl]carbonyl}-4-{2-[5-

(trifluoromethyl)-2-pyrazinyl]ethyl}-3-azabicyclo[4.1.OJheptane;

(lR,4R,6R)-3-{[5-methyl-2-(2-pyrimidinyl)phenyl]carbonyl}-4-{2-[5-(trifluoromethyl)-2- pyrazinyl]ethyl}-3-azabicyclo[4.1.OJheptane;

(lR,4R,6R)-3-{[6-methyl-3-(2-pyrimidinyl)-2-pyridinyl]carbonyl}-4-{2-[6- (trifluoromethyl)-2-pyrazinyl]ethyl}-3-azabicyclo[4.1.OJheptane;

(lR,4R,6R)-4-[2-(5,6-dimethyl-2-pyrazinyl)ethyl]-3-{[6-methyl-3-(2H-l,2,3-triazol-2-yl)-2- pyridinyl]carbonyl}-3-azabicyclo[4.1. OJheptane;

(lS,4R,6S)-3-{[6-methyl-3-(2-pyrimidinyl)-2-pyridinyl]carbonyl}-4-{2-[5- (trifluoromethyl)-2-pyrazinyl]ethyl}-3-azabicyclo[4.1.OJheptane; and

(lR,4R,6R)-4-[2-(5,6-dimethyl-l,2,4-triazin-3-yl)ethyl]-3-{[6-methyl-3-(2-pyrimidinyl)-2- pyridinyl]carbonyl}-3-azabicyclo[4.1.0]heptanes;

or a pharmaceutically acceptable salt thereof. The Het group may be attached to the ethylene linker by means of a bond between the carbon atom in said linker and any carbon or nitrogen atom in said Het group..

Preferably the Het group is attached to the linker by means of a bond between the carbon atom in the linker and a carbon atom in the Het group ring.

When Ri or R₂ is a heterocyclic group it can be any 5 or 6 membered heterocyclyl group containing 1, 2 or 3 atoms selected from N, O or S. Examples of such heterocyclic groups include pyrimidinyl, oxadiazolyl, oxazolyl, isoxazolyl, thiazolyl, triazolyl, imidazolyl, pyrazolinyl, pyridazinyl, pyrazinyl, pyridinyl, furanyl, thienyl, pyrrolyl, thiadiazolyl, triazinyl and isothiazolyl.

When Ri or R₂ is a heterocyclic group, said group may be attached to the X/Y containing ring by means of a bond between a carbon atom of said X/Y containing ring and a carbon or a heteroatom of the heterocyclic group. For example where Ri is a triazolyl group the attachment to the X/Y containing ring may be by means of a bond between a carbon atom on the X/Y containing ring and a) one of the two carbon atoms or b) one of the three nitrogen atoms of the triazolyl group.

When the compound contains a Ci_-4alkyl group, whether alone or forming part of a larger group, e.g. Ci_-4alkoxy, the alkyl group may be straight chain, branched or cyclic, or combinations thereof. Examples of Ci_-4alkyl are methyl or ethyl.

Examples of haloCi_-4alkyl include trifluoromethyl (i.e. -CF₃).

Examples of Ci_-4alkoxy include methoxy and ethoxy.

Examples of haloCi_-4alkoxy include trifluoromethoxy (i.e. - OCF₃).

Halogen or "halo" (when used, for example, in haloCi_-4alkyl) means fluoro, chloro, bromo or iodo.

It is to be understood that the present invention covers all combinations of particularised groups and substituents described herein above.

It will be appreciated that for use in medicine the salts of the compounds of formula (I) should be pharmaceutically acceptable. Suitable pharmaceutically acceptable salts will be apparent to those skilled in the art. Pharmaceutically acceptable salts include those described by Berge, Bighley and Monkhouse J.Pharm.Sci (1977) 66, pp 1-19. Such pharmaceutically acceptable salts include acid addition salts formed with inorganic acids e.g. hydrochloric, hydrobromic, sulphuric, nitric or phosphoric acid and organic acids e.g. succinic, maleic, acetic, fumaric, citric, tartaric, benzoic, p-toluenesulfonic, methanesulfonic or naphthalenesulfonic acid. Other salts e.g. oxalates or formates, may be used, for example in the isolation of compounds of formula (I) and represent another aspect of this invention.

Certain of the compounds of formula (I) may form acid addition salts with one or more equivalents of the acid. The present invention includes within its scope all possible stoichiometric and non-stoichiometric forms.

The compounds of formula (I) may be prepared in crystalline or non-crystalline form and, if crystalline, may optionally be solvated, eg. as the hydrate. This invention includes within its scope stoichiometric solvates (eg. hydrates) as well as compounds containing variable amounts of solvent (eg. water).

As used herein "pharmaceutically acceptable derivative" includes any

pharmaceutically acceptable ester or salt of such ester of a compound of formula (I) which, upon administration to the recipient is capable of providing (directly or indirectly) a compound of formula (I) or an active metabolite or residue thereof.

The stereogenic centres of the compounds of formula (I) are in a (1S,4R,6S)- or a a trans (\R,4R,6R)- configuration. The invention also extends to any tautomeric forms or mixtures thereof.

The subject invention also includes isotopically-labeled compounds which are identical to those recited in formula (I) but for the fact that one or more atoms are replaced by an atom having an atomic mass or mass number different from the atomic mass or mass number most commonly found in nature. Examples of isotopes that can be incorporated into compounds of the invention include isotopes of hydrogen, carbon, nitrogen, oxygen, fluorine, iodine and chlorine such as ¾ ^UC, ¹⁴C, ¹⁸F, ¹²³I or ¹²⁵I.

Compounds of the present invention and pharmaceutically acceptable salts of said compounds that contain the aforementioned isotopes and/or other isotopes of other atoms are within the scope of the present invention. Isotopically labeled compounds of the present invention, for example those into which radioactive isotopes such as ³H or ¹⁴C have been incorporated, are useful in drug and/or substrate tissue distribution assays. Tritiated, ie. ³H, and carbon-14, ie. ¹⁴C, isotopes are particularly preferred for their ease of preparation and detectability. ^UC and ¹⁸F isotopes are particularly useful in PET (positron emission tomography).

Since the compounds of formula (I) are intended for use in pharmaceutical compositions it will readily be understood that they are each preferably provided in substantially pure form, for example at least 60% pure, more suitably at least 75% pure and preferably at least 85%, especially at least 98% pure (% are on a weight for weight basis). Impure preparations of the compounds may be used for preparing the more pure forms used in the pharmaceutical compositions.

According to a further aspect of the present invention there is provided a process for the preparation of compounds of formula (I) and derivatives thereof. The following schemes detail some synthetic routes to compounds of the invention. In the following schemes reactive groups can be protected with protecting groups and deprotected according to well established techniques.

Schemes

According to a further aspect of the invention there is provided a process for the preparation of compounds of formula (I) or salts thereof. The following 3 schemes are examples of synthetic schemes that may be used to synthesise the compounds of the invention. In the schemes Het has the meaning given in formula (I), and the group Ar₁ denotes the 6 membered X/Y containing ring

wherein X, Y, R_1? R₂, R₃, m and n all have the meanings given in formula (I):

Scheme 1



Scheme 3

NaN0₂

DC / buffer solution pH=5

It will be understood by those skilled in the art that certain compounds of the invention can be converted into other compounds of the invention according to standard chemical methods.

The starting materials for use in the scheme are commercially available, known in the literature or can be prepared by known methods.

Pharmaceutically acceptable salts may be prepared conventionally by reaction with the appropriate acid or acid derivative.

The present invention provides compounds of formula (I) or a pharmaceutically acceptable salt thereof for use in human or veterinary medicine.

The compounds of formula (I) or their pharmaceutically acceptable salts may be of use for the treatment or prophylaxis of a disease or disorder where an antagonist of a human orexin receptor is required.

Coumpounds of formula (I) or their pharmaceutically acceptable salts may be of use for the treatment or prophylaxis of sleep disorders selected from the group consisting of Dyssomnias such as Primary Insomnia (307.42), Primary Hypersomnia (307.44),

Narcolepsy (347), Breathing-Related Sleep Disorders (780.59), Circadian Rhythm Sleep Disorder (307.45) and Dyssomnia Not Otherwise Specified (307.47); primary sleep disorders such as Parasomnias such as Nightmare Disorder (307.47), Sleep Terror Disorder (307.46), Sleepwalking Disorder (307.46) and Parasomnia Not Otherwise Specified (307.47); Sleep Disorders Related to Another Mental Disorder such as Insomnia Related to Another Mental Disorder (307.42) and Hypersomnia Related to Another Mental Disorder (307.44); Sleep Disorder Due to a General Medical Condition, in particular sleep disturbances associated with such diseases as neurological disorders, neuropathic pain, restless leg syndrome, heart and lung diseases; and Substance-Induced Sleep Disorder including the subtypes Insomnia Type, Hypersomnia Type, Parasomnia Type and Mixed Type; Sleep Apnea and Jet-Lag Syndrome.

In addition the compounds of formula (I) or their pharmaceutically acceptable salts may be of use for the treatment or prophylaxis of depression and mood disorders including Major Depressive Episode, Manic Episode, Mixed Episode and Hypomanic Episode;

Depressive Disorders including Major Depressive Disorder, Dysthymic Disorder (300.4), Depressive Disorder Not Otherwise Specified (311); Bipolar Disorders including Bipolar I Disorder, Bipolar Π Disorder (Recurrent Major Depressive Episodes with Hypomanic Episodes) (296.89), Cyclothymic Disorder (301.13) and Bipolar Disorder Not Otherwise Specified (296.80); Other Mood Disorders including Mood Disorder Due to a General Medical Condition (293.83) which includes the subtypes With Depressive Features, With Major Depressive-like Episode, With Manic Features and With Mixed Features),

Substance-Induced Mood Disorder (including the subtypes With Depressive Features, With Manic Features and With Mixed Features) and Mood Disorder Not Otherwise Specified (296.90).

Further, the compounds of formula (I) or their pharmaceutically acceptable salts may be of use for the treatment or prophylaxis of anxiety disorders including Panic Attack; Panic Disorder including Panic Disorder without Agoraphobia (300.01) and Panic Disorder with Agoraphobia (300.21); Agoraphobia; Agoraphobia Without History of Panic Disorder (300.22), Specific Phobia (300.29, formerly Simple Phobia) including the subtypes Animal Type, Natural Environment Type, Blood-Injection-Injury Type, Situational Type and Other Type), Social Phobia (Social Anxiety Disorder, 300.23), Obsessive-Compulsive Disorder (300.3), Posttraumatic Stress Disorder (309.81), Acute Stress Disorder (308.3), Generalized Anxiety Disorder (300.02), Anxiety Disorder Due to a General Medical Condition (293.84), Substance-Induced Anxiety Disorder, Separation Anxiety Disorder (309.21), Adjustment Disorders with Anxiety (309.24) and Anxiety Disorder Not Otherwise Specified (300.00).

In addition the compounds of formula (I) or their pharmaceutically acceptable salts may be of use for the treatment or prophylaxis of substance-related disorders including Substance Use Disorders such as Substance Dependence, Substance Craving and Substance Abuse; Substance-Induced Disorders such as Substance Intoxication, Substance

Withdrawal, Substance-Induced Delirium, Substance-Induced Persisting Dementia, Substance-Induced Persisting Amnestic Disorder, Substance-Induced Psychotic Disorder, Substance-Induced Mood Disorder, Substance-Induced Anxiety Disorder, Substance- Induced Sexual Dysfunction, Substance-Induced Sleep Disorder and Hallucinogen

Persisting Perception Disorder (Flashbacks); Alcohol -Related Disorders such as Alcohol Dependence (303.90), Alcohol Abuse (305.00), Alcohol Intoxication (303.00), Alcohol Withdrawal (291.81), Alcohol Intoxication Delirium, Alcohol Withdrawal Delirium, Alcohol -Induced Persisting Dementia, Alcohol-Induced Persisting Amnestic Disorder, Alcohol -Induced Psychotic Disorder, Alcohol-Induced Mood Disorder, Alcohol-Induced Anxiety Disorder, Alcohol-Induced Sexual Dysfunction, Alcohol -Induced Sleep Disorder and Alcohol-Related Disorder Not Otherwise Specified (291.9); Amphetamine (or

Amphetamine-Like)-Related Disorders such as Amphetamine Dependence (304.40), Amphetamine Abuse (305.70), Amphetamine Intoxication (292.89), Amphetamine

Withdrawal (292.0), Amphetamine Intoxication Delirium, Amphetamine Induced Psychotic Disorder, Amphetamine-Induced Mood Disorder, Amphetamine-Induced Anxiety Disorder, Amphetamine-Induced Sexual Dysfunction, Amphetamine-Induced Sleep Disorder and Amphetamine-Related Disorder Not Otherwise Specified (292.9); Caffeine Related

Disorders such as Caffeine Intoxication (305.90), Caffeine-Induced Anxiety Disorder, Caffeine-Induced Sleep Disorder and Caffeine-Related Disorder Not Otherwise Specified (292.9); Cannabis-Related Disorders such as Cannabis Dependence (304.30), Cannabis Abuse (305.20), Cannabis Intoxication (292.89), Cannabis Intoxication Delirium, Cannabis- Induced Psychotic Disorder, Cannabis-Induced Anxiety Disorder and Cannabis-Related Disorder Not Otherwise Specified (292.9); Cocaine-Related Disorders such as Cocaine Dependence (304.20), Cocaine Abuse (305.60), Cocaine Intoxication (292.89), Cocaine Withdrawal (292.0), Cocaine Intoxication Delirium, Cocaine-Induced Psychotic Disorder, Cocaine-Induced Mood Disorder, Cocaine-Induced Anxiety Disorder, Cocaine-Induced Sexual Dysfunction, Cocaine-Induced Sleep Disorder and Cocaine-Related Disorder Not Otherwise Specified (292.9); Hallucinogen-Related Disorders such as Hallucinogen Dependence (304.50), Hallucinogen Abuse (305.30), Hallucinogen Intoxication (292.89), Hallucinogen Persisting Perception Disorder (Flashbacks) (292.89), Hallucinogen

Intoxication Delirium, Hallucinogen-Induced Psychotic Disorder, Hallucinogen-Induced Mood Disorder, Hallucinogen-Induced Anxiety Disorder and Hallucinogen-Related Disorder Not Otherwise Specified (292.9); Inhalant-Related Disorders such as Inhalant Dependence (304.60), Inhalant Abuse (305.90), Inhalant Intoxication (292.89), Inhalant Intoxication Delirium, Inhalant-Induced Persisting Dementia, Inhalant-Induced Psychotic Disorder, Inhalant-Induced Mood Disorder, Inhalant-Induced Anxiety Disorder and

Inhalant-Related Disorder Not Otherwise Specified (292.9); Nicotine-Related Disorders such as Nicotine Dependence (305.1), Nicotine Withdrawal (292.0) and Nicotine-Related Disorder Not Otherwise Specified (292.9); Opioid-Related Disorders such as Opioid Dependence (304.00), Opioid Abuse (305.50), Opioid Intoxication (292.89), Opioid Withdrawal (292.0), Opioid Intoxication Delirium, Opioid-Induced Psychotic Disorder, Opioid-Induced Mood Disorder, Opioid-Induced Sexual Dysfunction, Opioid-Induced Sleep Disorder and Opioid-Related Disorder Not Otherwise Specified (292.9); Phencyclidine (or Phencyclidine-Like)-Related Disorders such as Phencyclidine Dependence (304.60), Phencyclidine Abuse (305.90), Phencyclidine Intoxication (292.89), Phencyclidine

Intoxication Delirium, Phencyclidine-Induced Psychotic Disorder, Phencyclidine-Induced Mood Disorder, Phencyclidine-Induced Anxiety Disorder and Phencyclidine-Related Disorder Not Otherwise Specified (292.9); Sedative-, Hypnotic-, or Anxiolytic-Related Disorders such as Sedative, Hypnotic, or Anxiolytic Dependence (304.10), Sedative, Hypnotic, or Anxiolytic Abuse (305.40), Sedative, Hypnotic, or Anxiolytic Intoxication (292.89), Sedative, Hypnotic, or Anxiolytic Withdrawal (292.0), Sedative, Hypnotic, or Anxiolytic Intoxication Delirium, Sedative, Hypnotic, or Anxiolytic Withdrawal Delirium, Sedative-, Hypnotic-, or Anxiolytic-Persisting Dementia, Sedative-, Hypnotic-, or

Anxiolytic- Persisting Amnestic Disorder, Sedative-, Hypnotic-, or Anxiolytic-Induced Psychotic Disorder, Sedative-, Hypnotic-, or Anxiolytic-Induced Mood Disorder, Sedative-, Hypnotic-, or Anxiolytic-Induced Anxiety Disorder Sedative-, Hypnotic-, or Anxiolytic- Induced Sexual Dysfunction, Sedative-, Hypnotic-, or Anxiolytic-Induced Sleep Disorder and Sedative-, Hypnotic-, or Anxiolytic-Related Disorder Not Otherwise Specified (292.9); Poly sub stance-Related Disorder such as Polysubstance Dependence (304.80); and Other (or Unknown) Substance-Related Disorders such as Anabolic Steroids, Nitrate Inhalants and Nitrous Oxide.

In addition the compounds of formula (I) or their pharmaceutically acceptable salts may be of use for the treatment or prophylaxis of feeding disorders such as bulimia nervosa, binge eating, obesity, including obesity observed in Type 2 (non-insulin-dependent) diabetes patients. Further, the compounds of formula (I) or their pharmaceutically acceptable salts may be of use for the treatment or prophylaxis of stroke, particularly ischemic or haemorrhagic stroke and/or in blocking an emetic response i.e. nausea and vomiting.

The numbers in brackets after the listed diseases refer to the classification code in DSM-IV: Diagnostic and Statistical Manual of Mental Disorders, 4th Edition, published by the American Psychiatric Association. The various subtypes of the disorders mentioned herein are contemplated as part of the present invention.

The invention also provides a method for the treatment of a disease or disorder in a subject, for example those diseases and disorders mentioned hereinabove, comprising administering to said subject an effective amount of a compound of formula (I), or a pharmaceutically acceptable salt thereof. The invention also provides a compound of formula (I), or a pharmaceutically acceptable salt thereof, for use in the treatment or prophylaxis of a disease or disorder, for example those diseases and disorders mentioned hereinabove.

The invention also provides the use of a compound of formula (I), or a

pharmaceutically acceptable salt thereof, in the manufacture of a medicament for use in the treatment or prophylaxis of a disease or disorder, for example those diseases and disorders mentioned hereinabove.

For use in therapy the compounds of the invention are usually administered as a pharmaceutical composition. The invention also provides a pharmaceutical composition comprising a compound of formula (I), or a pharmaceutically acceptable salt thereof, and a pharmaceutically acceptable carrier.

The compounds of formula (I) or their pharmaceutically acceptable salts may be administered by any convenient method, e.g. by oral, parenteral, buccal, sublingual, nasal, rectal or transdermal administration, and the pharmaceutical compositions adapted accordingly.

The compounds of formula (I) or their pharmaceutically acceptable salts which are active when given orally can be formulated as liquids or solids, e.g. as syrups, suspensions, emulsions, tablets, capsules or lozenges.

A liquid formulation will generally consist of a suspension or solution of the active ingredient in a suitable liquid carrier(s) e.g. an aqueous solvent such as water, ethanol or glycerine, or a non-aqueous solvent, such as polyethylene glycol or an oil. The formulation may also contain a suspending agent, preservative, flavouring and/or colouring agent.

A composition in the form of a tablet can be prepared using any suitable

pharmaceutical carrier(s) routinely used for preparing solid formulations, such as magnesium stearate, starch, lactose, sucrose and cellulose.

A composition in the form of a capsule can be prepared using routine encapsulation procedures, e.g. pellets containing the active ingredient can be prepared using standard carriers and then filled into a hard gelatin capsule; alternatively a dispersion or suspension can be prepared using any suitable pharmaceutical carrier(s), e.g. aqueous gums, celluloses, silicates or oils and the dispersion or suspension then filled into a soft gelatin capsule.

Typical parenteral compositions consist of a solution or suspension of the active ingredient in a sterile aqueous carrier or parenterally acceptable oil, e.g. polyethylene glycol, polyvinyl pyrrolidone, lecithin, arachis oil or sesame oil. Alternatively, the solution can be lyophilised and then reconstituted with a suitable solvent just prior to administration.

Compositions for nasal administration may conveniently be formulated as aerosols, drops, gels and powders. Aerosol formulations typically comprise a solution or fine suspension of the active ingredient in a pharmaceutically acceptable aqueous or nonaqueous solvent and are usually presented in single or multidose quantities in sterile form in a sealed container which can take the form of a cartridge or refill for use with an atomising device. Alternatively the sealed container may be a disposable dispensing device such as a single dose nasal inhaler or an aerosol dispenser fitted with a metering valve. Where the dosage form comprises an aerosol dispenser, it will contain a propellant which can be a compressed gas e.g. air, or an organic propellant such as a fluorochlorohydrocarbon or hydrofluorocarbon. Aerosol dosage forms can also take the form of pump-atomisers.

Compositions suitable for buccal or sublingual administration include tablets, lozenges and pastilles where the active ingredient is formulated with a carrier such as sugar and acacia, tragacanth, or gelatin and glycerin.

Compositions for rectal administration are conveniently in the form of suppositories containing a conventional suppository base such as cocoa butter.

Compositions suitable for transdermal administration include ointments, gels and patches.

In one embodiment the composition is in unit dose form such as a tablet, capsule or ampoule.

The composition may contain from 0.1% to 100% by weight, for example from 10 to 60% by weight, of the active material, depending on the method of administration. The composition may contain from 0% to 99% by weight, for example 40% to 90% by weight, of the carrier, depending on the method of administration. The composition may contain from 0.05mg to lOOOmg, for example from l .Omg to 500mg, of the active material, depending on the method of administration. The composition may contain from 50 mg to 1000 mg, for example from lOOmg to 400mg of the carrier, depending on the method of administration. The dose of the compound used in the treatment of the aforementioned disorders will vary in the usual way with the seriousness of the disorders, the weight of the sufferer, and other similar factors. However, as a general guide suitable unit doses may be 0.05 to 1000 mg, more suitably 1.0 to 500 mg, and such unit doses may be administered more than once a day, for example two or three a day. Such therapy may extend for a number of weeks or months.

Orexin-A (Sakurai, T. et al (1998) Cell, 92 pp 573-585) can be employed in screening procedures for compounds which inhibit the ligand' s activation of the orexin-1 or orexin-2 receptors.

In general, such screening procedures involve providing appropriate cells which express the orexin-1 or orexin-2 receptor on their surface. Such cells include cells from mammals, yeast, Drosophila or s. coli. In particular, a polynucleotide encoding the orexin- 1 or orexin-2 receptor is used to transfect cells to express the receptor. The expressed receptor is then contacted with a test compound and an orexin-1 or orexin-2 receptor ligand, as appropriate, to observe inhibition of a functional response. One such screening procedure involves the use of melanophores which are transfected to express the orexin-1 or orexin-2 receptor, as described in WO 92/01810.

Another screening procedure involves introducing RNA encoding the orexin-1 or orexin-2 receptor into Xenopus oocytes to transiently express the receptor. The receptor oocytes are then contacted with a receptor ligand and a test compound, followed by detection of inhibition of a signal in the case of screening for compounds which are thought to inhibit activation of the receptor by the ligand.

Another method involves screening for compounds which inhibit activation of the receptor by determining inhibition of binding of a labelled orexin-1 or orexin-2 receptor ligand to cells which have the orexin-1 or orexin-2 receptor (as appropriate) on their surface. This method involves transfecting a eukaryotic cell with DNA encoding the orexin-1 or orexin-2 receptor such that the cell expresses the receptor on its surface and contacting the cell or cell membrane preparation with a compound in the presence of a labelled form of an orexin-1 or orexin-2 receptor ligand. The ligand may contain a radioactive label. The amount of labelled ligand bound to the receptors is measured, e.g. by measuring

radioactivity.

Yet another screening technique involves the use of FLIPR equipment for high throughput screening of test compounds that inhibit mobilisation of intracellular calcium ions, or other ions, by affecting the interaction of an orexin-1 or orexin-2 receptor ligand with the orexin-1 or orexin-2 receptor as appropriate.

Throughout the specification and claims which follow, unless the context requires otherwise, the word 'comprise', and variations such as 'comprises' and 'comprising' will be understood to imply the inclusion of a stated integer or step or group of integers or steps but not to the exclusion of any other integer or step or group of integers or steps.

All publications, including but not limited to patents and patent applications, cited in this specification are herein incorporated by reference as if each individual publication were specifically and individually indicated to be incorporated by reference herein as though fully set forth.

The following Examples illustrate the preparation of certain compounds of formula (I) or salts thereof. The Descriptions 1 to 73 illustrate the preparation of intermediates used to make compounds of formula (I) or salts thereof.

In the procedures that follow, after each starting material, reference to a description is typically provided. This is provided merely for assistance to the skilled chemist. The starting material may not necessarily have been prepared from the Description referred to.

The yields were calculated assuming that products were 100 % pure if not stated otherwise.

The compounds described in the Examples described hereinafter have all been prepared as a first step from stereochemically pure starting materials. The stereochemistry of the compounds of the Descriptions and Examples have been assigned on the assumption that the absolute configuration of these centres are retained. The relative stereochemistry of the compounds of the Descriptions and Examples have been assigned on the assumption that the relative stereochemistry is maintained as determined by using Rotating frame 2D ROESY experiments in the chiral intermediates. In some Examples the relative

stereochemistry has been confirmed on the final compounds as well.

Compounds are named using ACD/Name PRO 6.02 chemical naming software

(Advanced Chemistry Development Inc., Toronto, Ontario, M5H2L3, Canada).

Proton Magnetic Resonance ( MR) spectra were recorded either on Varian instrument at 400, 500 or 600 MHz, or on a Bruker instrument at 400 MHz. Chemical shifts are reported in ppm (δ) using the residual solvent line as internal standard. Splitting patterns are designed as s, singlet; d, doublet; t, triplet; q, quartet; m, multiplet; b, broad. The NMR spectra were recorded at a temperature ranging from 25 to 90 °C. When more than one conform er was detected the chemical shifts for the most abundant one is usually reported. Unless otherwise specified, HPLC analyses indicated by HPLC (walk-up): rt (retention time) = x min, were performed on a Agilent 1100 series instrument using a Luna 3u CI 8(2) 100A column (50 x 2.0 mm, 3 μπι particle size) [Mobile phase and Gradient: 100% (water + 0.05% TFA) to 95% (acetonitrile + 0.05% TFA) in 8 min. Column T = 40 °C. Flow rate = 1 mL/min. UV detection wavelength = 220 nm]. Other HPLC analyses, indicated by HPLC (walk-up, 3 min method), were performed using an Agilent Zorbax SB- C18 column (50 x 3.0 mm, 1.8 μπι particle size) [Mobile phase and Gradient: (Solvent A: water + 0.05% TFA) (Solvent B: acetonitrile + 0.05% TFA) Gradient: time 0 min 0% B. From 0 to 95% B in 2.5 min. 95% B for 0.2 min. From 95 to 100% B in 0.2 min. 100% B for 0.4 min. From 100% to 0% B in 0. lmin. Flow rate = 1.5 mL/min. UV detection wavelength = 220 nm]

In the analytical characterization of the described compounds "MS" refers to Mass Spectra taken by Direct infusion Mass or to Mass Spectra associated with peaks taken by UPLC/MS or HPLC/MS analysis, where the Mass Spectrometer used is as mentioned below.

Direct infusion Mass spectra (MS) were run on a Agilent MSD 1100 Mass

Spectrometer, operating in ES (+) and ES (-) ionization mode [ES (+): Mass range: 100- 1000 amu. Infusion solvent: water + 0.1% HC0₂H / CH₃CN 50/50. ES (-): Mass range: 100-1000 amu. Infusion solvent: water + 0.05% H₄OH / CH₃CN 50/50]

MS spectra associated with the peaks were taken on HPLC instrument Perkin Elmer 200 series coupled to an Applied Biosystems API150EX Mass Spectrometer.

UV and MS spectra associated with the peaks were taken on HPLC instrument Agilent 1100 Series coupled to an Agilent LC/MSD 1100 Mass Spectrometer operating in positive or negative electrospray ionization mode and in both acidic and basic gradient conditions

[Acidic gradient LC/MS - ES (+ or -): analyses performed on a Supelcosil ABZ + Plus column (33 x 4.6 mm, 3 μιη). Mobile phase: A - water + 0.1% HC0₂H / B - CH₃CN.

Gradient (standard method): t=0 min 0% (B), from 0% (B) to 95% (B) in 5 min lasting for

1.5 min, from 95% (B) to 0%(B) in 0.1 min, stop time 8.5 min. Column T = room temperature. Flow rate = 1 mL/min. Gradient (fast method): t=0 min 0% (B), from 0% (B) to 95% (B) in 3 min lasting for 1 min, from 95% (B) to 0% (B) in 0.1 min, stop time 4.5 min. Column T = room temperature. Flow rate = 2 mL/min.

Basic gradient LC/MS - ES (+ or -): analyses performed on a XTerra MS CI 8 column (30 x

4.6 mm, 2.5 μιη). Mobile phase: A - 5 mM aq. H₄HC0₃ + ammonia (pH 10) / B - CH₃CN. Gradient: t = 0 min 0% (B), from 0% (B) to 50% (B) in 0.4 min, from 50% (B) to 95% (B) in 3.6 min lasting for 1 min, from 95% (B) to 0% (B) in 0.1 min, stop time 5.8 min. column temperature = room temperature. Flow rate = 1.5 mL/min].

Mass range ES (+ or -): 100-1000 amu. UV detection range: 220-350 nm. The usage of this methodology is indicated by "LC-MS" in the analytic characterization of the described compounds.

Total ion current (TIC) and DAD UV chromatographic traces together with MS and

UV spectra associated with the peaks were taken on a UPLC/MS Acquity™ system equipped with 2996 PDA detector and coupled to a Waters Micromass ZQ™ Mass Spectrometer operating in positive or negative electrospray ionisation mode [LC/MS - ES (+ or -): analyses performed using an AcquityTM UPLC BEH C18 column (50 x 21 mm, 1.7 μιη particle size), column temperature 40 °C]. Mobile phase: A-water + 0.1% HCOOH / B - CH₃CN + 0.075% HCOOH, Flow rate: 1.0 mL/min, Gradient: t=0 min 3% B, t=0.05 min 6% B, t= 0.57 min 70% B, t=l .4 min 99% B, t=l .45 min 3% B). The usage of this methodology is indicated by "UPLC" in the analytic characterization of the described compounds.

[LC/MS - ES (+ or -): analyses performed using an Acquity™ UPLC BEH CI 8 column (50 x 2.1 mm, 1.7 μιη particle size) column temperature 40 °C]. Mobile phase: A - water + 0.1% HC0₂H / B - CH₃CN + 0.06% or 0.1% HC0₂H Gradient: t = 0 min 3% B, t =1.5 min 100% B, t = 1.9 min 100% B, t = 2 min 3% B stop time 2 min. Column T = 40 °C. Flow rate = 1.0 mL/min. Mass range: ES (+): 100-1000 amu or ES(+): 50-800 amu. ES (-): 100- 800 amu. UV detection range: 210-350 nm. The usage of this methodology is indicated by "UPLC (Acid IPQC)" in the analytic characterization of the described compounds.

[LC/MS - ES (+ or -): analyses performed using an Acquity™ UPLC BEH C 18 column (50 x 2.1 mm, 1.7 μιη particle size) column temperature 40 °C]. Mobile phase: A - water + 0.1% HC0₂H / B - CH₃CN + 0.06% or 0.1% HC0₂H. Gradient: t = 0 min 3% B, t = 0.05 min 6% B, t = 0.57 min 70% B, t = 1.06 min 99% B lasting for 0.389 min, t = 1.45 min 3% B, stop time 1.5 min. Column T = 40 °C. Flow rate = 1.0 mL/min. Mass range: ES (+): 100- 1000 amu or ES(+): 50-800 amu, ES (-): 100-800 amu. UV detection range: 210-350 nm. The usage of this methodology is indicated by "UPLC (Acid QC POS 50-800 or

QC POS 70 900 or GEN QC or FF AL QC)" in the analytic characterization of the described compounds.

[LC/MS - ES (+ or -): analyses performed using an Acquity™ UPLC BEH CI 8 column (50 x 2.1 mm, 1.7 μιη particle size) column temperature 40 °C]. Mobile phase: A - water + 0.1% HC0₂H / B - CH₃CN + 0.06% or 0.1% HC0₂H. Gradient: t = 0 min 3% B, t = 1.06 min 99 % B, t = 1.45 min 99 % B, t = 1.46 min 3 % B, stop time 1.5 min. Column T = 40 °C. Flow rate = 1.0 mL/min. Mass range: ES (+): 100-1000 amu. ES (-): 100-800 amu. UV detection range: 210-350 nm. The usage of this methodology is indicated by "UPLC (Acid GEN QC SS)" in the analytic characterization of the described compounds.

Total ion current (TIC) and DAD UV chromatographic traces together with MS and UV spectra associated with the peaks were taken on a UPLC/MS Acquity™ system equipped with PDA detector and coupled to a Waters SQD mass spectrometer operating in positive and negative alternate electrospray ionisation mode [LC/MS - ES(+ or -): analyses performed using an Acquity™ UPLC BEH C 18 column (50 x 2.1 mm, 1.7 μιη particle size) column temperature 40 °C]. Mobile phase: A - 10 mM aqueous solution of NH₄HC0₃ (adjusted to pH 10 with ammonia) / B - CH₃CN. Gradient: t = 0 min 3% B, t = 1.06 min 99% B lasting for 0.39 min, t = 1.46 min 3% B, stop time 1.5 min. Column T = 40 °C. Flow rate = 1.0 mL/min. Mass range: ES (+): 100-1000 amu or ES (+): 50-800 amu. ES (-): 100- 1000 amu. UV detection range: 220-350 nm. The usage of this methodology is indicated by "UPLC (Basic GEN QC or QC POS 50-800)" in the analytic characterization of the described compounds. Unless otherwise specified, Preparative LC-MS purifications were run on a MDAP- ZQ (FractionLynx) Waters instrument, using a Sunfire C18 OBD (100 x 19 mm x 5 μπι) column at room temperature. The injection volume was 50 μΐ. Mobile phase: A = 0.1% v/v solution of formic acid in water; B = Acetonitrile. Flow rate: 17 ml/min.

Preparative purification gradient: t = 0 min 45% B, t = 8 min 75% B, t = 10 min 100% B, t = 11 min 45% B.

For reactions involving microwave irradiation, a Personal Chemistry EmrysTM Optimizer was used.

In a number of preparations, purification was performed using Biotage manual flash chromatography (Flash+), Biotage automatic flash chromatography (Horizon, SP1 and SP4), Companion CombiFlash (ISCO) automatic flash chromatography, Flash Master Personal or Vac Master systems.

Flash chromatography was carried out on silica gel 230-400 mesh (supplied by Merck AG Darmstadt, Germany), Varian Mega Be-Si pre-packed cartridges, pre-packed Biotage silica cartridges (e.g. Biotage SNAP cartridge), KP-NH prepacked flash cartridges or ISCO RediSep Silica cartridges.

SPE-SCX cartridges are ion exchange solid phase extraction columns supplied by Varian. The eluent used with SPE-SCX cartridges is DCM and MeOH or ACN or MeOH followed by 2 N ammonia solution in MeOH. The collected fractions are those eluted with the ammonia solution in MeOH.

SPE-Si cartridges are silica solid phase extraction columns supplied by Varian.

ENV+ cartridges are packed with ENV+ a hyper cross-linked hydroxylated polystyrene-divinylbenzene copolymer.

The following table lists the used abbreviations:

ACN Acetonitrile

AcOH Acetic acid

bs or br.s. broad signal

Boc t-Butoxycarbonyl

Burgess reagent Methyl N-(triethylammoniumsulphonyl)carbamate

CBr₄ Carbon tetrabromide

CV Column volumes

Cy Cyclohexanes

DBU 1,8-Diazabicyclo[5.4.0] undec-7-ene

DCE Dichloroethane

DCM Dichloromethane

Dess-Martin 1, 1, l-Tris(acetoxy)-l, l-dihydro-l,2-benziodoxol-3-(lH)-one periodinane

DIAD Diisopropyl azodicarboxylate

DIPEA N,N-Diisopropyl-N-ethylamine

DMF Dimethylformamide

DMSO Dimethylsulfoxide EtOAc Ethyl acetate

EtOH Ethanol

Lindlar Catalyst 2,2' -(ethyl enedithio)di ethanol

MeOH Methanol

min Minutes

MTBE Methyl tertiary butyl ether

NMP N-Methyl-2-pyrrolidone

Ph Phenyl

pH=3 buffer Citric acid/NaOH/HCl in water solution available from Merck solution KGaA

rt retention time

T temperature

TBAF Tetrabutyl ammonium fluoride

TBDMS fert-Butyl dimethylsilyl

TBDPS fert-Butyl diphenylsilyl

TBTU O-(benzotriazol-l-yl)-N,N;N'N'-tetramethyluronium

tetrafluorob orate

tBu tert-butyl

TEA Tri ethyl amine

TEMPO 2,2,6,6-Tetramethylpiperidine- 1 -oxyl

TFA Trifluoroacetic acid

THF Tetrahydrofuran

TMS Trimethylsilyl

Ts ^-Toluensulfonyl

T₃P 1 -Propane phosphonic anhydride

Descriptions

Description 1: 1,1-dimethylethyl (lR,6R)-2-oxo-3-azab ic clo [4.1.0] heptane-4- carboxylate (Dl)

Sodium iodide (391 g, 2.6 mol) was partially dissolved in ACN (1.7 1) after stirring at 20°C for 10 minutes under nitrogen atmosphere. TMS-Cl (0.323 1, 2.5 mol) was added over 10 minutes and the resulting yellow slurry was stirred at 20°C for 1 hour. A solution of (lR,55)-3-oxabicyclo[3.1.0]hexan-2-one (Minakem supplier, 170 g, 1.73 mol) in ACN (340 ml) was added over 5 minutes at 20°C. The suspension was heated to 50°C (internal temperature), then kept for 3 hours and 45 minutes at 50°C. The mixture was diluted with MeOH (1.7 1) at 20°C and concentrated to 5 volumes (850 ml) under reduced pressure. MeOH (1.7 1) was then added followed by TMS-Cl (0.102 1, 0.8 mol). The resulting mixture was stirred at 20°C for 15 hours 30 minutes. The mixture was concentrated under vacuum to 5 volumes (0.85 1), then 2-MeTHF was added (1.7 1) and the solution was concentrated to 5 volumes (0.85 1). 2-MeTHF was added (1.7 1). The dark red solution was washed with aqueous Na₂S0₃ 20% w/w (0.68 1) at 20°C (solution became colourless-light yellow). The biphasic system was separated and the organic layer was washed with water (0.68 1), then concentrated under vacuum to 4 volumes (0.68 1). 2-MeTHF (1.7 1) was added and the solution of methyl (lR,2S)-2-(iodomethyl)cyclopropanecarboxylate was concentrated to 5 volumes (0.85 1), diluted with 2-Me-THF (0.51 1). N-(Diphenylmethylene)glycine t-butylester (503.2g, 1.7mol, 1.2 eq) was suspended in dry Me-THF (1.7L) at 20°C under nitrogen. The mixture was cooled to 0°C and KOtBu (195.5g, 1.74mol, 1 eq) was added in three portions. The slurry was become a yellow- orange solution and was stirred at 0°C for 30 minutes. The previous solution of methyl (lR,2S)-2-(iodomethyl)cyclopropanecarboxylate in 2-MeTHF was slowly added over 25 minutes, keeping the temperature lower than 5°C during the addition. The mixture was stirred at 0°C for 2.5 hours. The mixture was quenched with buffer pH=7

(KH₂P0₄/Na₂HP0₄) (340ml) at 0°C. The biphasic system was warmed at 20°C. The water phase was discharged. To the organic phase at 0°C was added citric acid 30% w/w (1.36L) keeping the temperature 0-5°C and the biphasic system was stirred for 16 hours 20 minutes at 20°C. Cyclohexane (3.4L) was added and the phases were separated. The water phase was washed with cyclohexane (3.4L). Ethyl acetate (3.4L) was added to the water phase, and then the system was basified to pH=8.5 with aqueous saturated K₂C0₃ (0.85L) then diluted with water (0.425L). The biphasic system was separated. The aqueous layer was back extracted with ethyl acetate (3.4L). The combined organic phases were washed with water (0.51L), concentrated to 10 volumes (1.7L). Toluene (3.4L) was added and the solution was concentrated to 10 volumes (1.7L), diluted again with toluene (0.85L). To this solution was added HC1 37% (0.85ml, catalytic amount). The solution was heated to 105°C for 20 hours. The solution was cooled at 40°C, reduced to 4 volumes (0.68L) under reduced pressure and heptane (1.19L) was added over lhour. The mixture was stirred at 40°C for 30 minutes and then cooled at 15°C over 1 hour: a solid was precipitated. The slurry was stirred at 15° for approximately 16 hours and then filtered. The solid was washed with heptane (2x0.425L), dried in a vacuum oven at 40°C for 20 hours and 30 minutes. 1,1 -dimethyl ethyl (lR,6R)-2-oxo-3-azabicyclo[4.1.0]heptane-4-carboxylate (syn/anti mixture, 194g) was obtained as white solid.

1H MR (600 MHz, DMSO-d6) δ ppm 6.86 - 7.39 (1 H, 2 m), 3.81 (1 H, 2 dd), 2.20 - 2.33 (1 H, 2 m), 1.74 - 2.11 (1 H, 2 m), 1.42 (9 H, s), 1.4 - 1.6 (1 H, m), 0.90 - 1.12 (1 H, 2 m), 0.69 - 0.88 (1 H, 2 m)

Description 2: l,l-dimethylethyl(lR,4S,6R)-4-(hydroxymethyl)-3- azabicyclo[4.1.0]heptane-3-carboxylate (D2)

The 1,1 -dimethyl ethyl (lR,6R)-2-oxo-3-azabicyclo[4.1.0]heptane-4-carboxylate, (150g, 1 eq) was dissolved in toluene (0.450L) and MeOH (1.05L) stirred for 5 minutes at 20°C. The temperature was cooled to 15°C and KOH (60g, 1.06 mol, 1.5eq) was added in two portions. The solution was stirred at 20°C for 3hours. The solution was cooled to 10°C, TMSCl (0.36L, 2.84 mol, 4eq) was added keeping the temperature around 10-15°C over 40 minutes. White solid was precipitated (KC1). The slurry was stirred at room temperature overnight. The pH of the organic phase was measured and found to be 1. NaHC0₃ solid (240g) was added in four portions to reach pH=5.5. The volume was reduced to 4 volumes (0.6L). THF (1.5L) was added and the volume is reduced to 4 volumes (0.6L) by distillation under reduced pressure. The solid was filtered (note: 60ml of the slurry was collected prior to filtration, so 10% of input was removed) and washed with THF (3x0.3L). The filtrate appeared cloudy. The solution was reduced to 2.2 volumes (0.337L) by distillation under reduced pressure and BF₃.THF (422.55mL, 3.83 mol, 6eq considering the 10% removed) was added under stirring whilst maintaining an internal temperature of 25°C. The resulting solution was added slowly to a solution of L1BH₄ (4M in THF) (0.648L, 2.59 mol, 4eq) diluted with THF (0.405L) keeping the temperature at 25-30°C (the line was washed with THF (0.337L)). The mixture was stirred at 30°C overnight (17 hours). The mixture was quenched slowly with MeOH (0.54L) at 25-30°C. The solution was stirred at 50°C for approximately 1 hour. After this time, the solution was reduced to 5.5 volumes (742.5 mL) by distillation under reduced pressure. HC1 3M (0.540L) was then added at 10-15°C. The mixture was stirred at 20°C for 1 hour and toluene (0.54L) was added. The phases were separated. The aqueous phase was washed with toluene (3x0.54L).The aqueous layer was basified with 6M NaOH (405mL) until pH=9. To the basic aqueous solution at 25°C were successively added THF (67.5 mL) and a solution of ditert-butyl dicarbonate in THF

(50%wt/vol, d=0.92, 0.25L, 0.626 mol, 0.93eq) The pH was adjusted to pH=8.5 by addition of 6M NaOH (0.135L). The resulting slurry was stirred for 30 minutes at 25°C and the pH was adjusted to pH=9 by addition of 6M NaOH (0.135L). The slurry was then stirred for 3hours and then filtered. The inorganic salts were washed with MTBE (2x0.27L). The filtrate was diluted with MTBE (1.08L). The biphasic system was separated. The organic phase was washed with NaCl 20%w/w (0.54L) and then concentrated under reduced pressure to 2.5 volumes (337.5 mL). Heptane (1.35L) was added and the solution was reduced to 5 volumes (0.675L), diluted with heptane (0.675L) and concentrated to 5 volumes (0.675L) by distillation under reduced pressure. Seed (135mg) of the title compound was added at 40°C and the slurry was cooled at 20°C in 1 hour. The slurry was stirred for at least 4 hours and filtered. The solid was washed with cold heptane (0.27L) and dried in a vacuum oven at 40°C for 14 hours and 30 minutes. l,l-dimethylethyl(lR,4S,6R)- 4-(hydroxymethyl)-3-azabicyclo[4.1.0]heptane-3-carboxylate (98g) was obtained as white solid.

1H MR (600 MHz, DMSO-d6) δ ppm 4.67 (1 H, br. s.), 3.6 - 3.9 (2 H, m), 3.2 - 3.5 (3 H, m), 1.89 (1 H, m), 1.54 (1 H, m), 1.37 (9 H, br. s.), 0.90 (2 H, m), 0.58 (1 H, m), -0.09 (1 H, q)

Description 3: 1,1-dimethylethyl (lR,4S,6R)-4-formyl-3-azabicyclo[4.1.0]heptane-3- carboxylate (D3)

To a solution of 1,1-dimethylethyl (lR,4S,6R)-4-(hydroxymethyl)-3- azabicyclo[4.1.0]heptane-3-carboxylate D2 (4 g) in dry DCM (126 ml) under nitrogen at room temperature, Dess-Martin periodinane (8.21 g, 19.36 mmol) was added portionwise then the mixture was stirred at room temperature for 3 hours. A saturated solution of

Na₂S₂03 was added and the mixture stirred for 10 minutes, then 15 ml of NaHC0₃ saturated solution were added and the mixture stirred for 5 minutes, then phases were separated; organic phase was washed with water, dried over phase separator filter tube and

concentrated under reduced pressure (cold bath) affording the title compound D3 (4.12 g). UPLC (Acid GEN_QC_SS) rt = 0.75 minutes, peak observed: 170 [M+1-C(CH₃)₃] Ci₂Hi₉N0₃ requires: 225.

1H MR (400 MHz, DMSO-i¾) δ ppm 0.16 (dq, 1 H) 0.61 (td, 1 H) 0.83 - 1.12 (m, 2 H) 1.25 - 1.44 (m, 9 H) 1.61 - 1.75 (m, 1 H) 2.19 - 2.31 (m, 1 H) 3.26 - 3.44 (m, 1 H) 3.48 - 3.75 (m, 1 H) 3.92 - 4.13 (m, 1 H) 9.45 (d, 1 H)

Description 4: 1,1-dimethylethyl (lR,4S,6R)-4-(2,2-dibromoethenyl)-3- azabicyclo[4.1.0]heptane-3-carboxylate (D4)

To a solution of triphenylphosphine (33.5 g, 128 mmol) and CBr₄ (21.20 g, 63.9 mmol) in dry DCM (123 ml) at 0°C, a solution of 1,1-dimethylethyl (lR,4S,6R)-4-formyl-3- azabicyclo[4.1.0]heptane-3-carboxylate D3 (7.2 g) in DCM (7 ml) was added dropwise. The reaction was stirred for 30 minutes at 0 °C then NaHC0₃ saturated solution was added and the mixture was allowed to reach room temperature, then layers were separated and organic one was dried over phase separator filter tube and concentrated. The residue was suspended in Cyclohexane/Et₂0 1 : 1 and stirred overnight. The day after it was filtered, solvent was evaporated under reduced pressure and the residue was suspended in Cyclohexane and stirred for 2 hours. The suspension was filtered again, solvent eliminated under reduced pressure, the residue suspended again in Cyclohexane and stirred for further 1 hour. Then it was filtered, solvent concentrated under reduced pressure and the residue was purified by flash chromatography on silica gel (SNAP lOOg, eluentCy to Cy/EtOAc 9: 1 in 10CV) affording the title compound D4 (9.8 g).

UPLC (Acid GEN_QC_SS) rt = 1.09 minutes, peak observed: 326 [(M+1-C(CH₃)₃] Ci₃Hi₉Br₂N0₂ requires: 381

1H NMR (400 MHz, CHLOROFORM-^ δ ppm 0.18 (br. s., 1 H) 0.73 (td, 1 H) 0.89 - 1.18 (m, 2 H) 1.37 - 1.55 (m, 9 H) 1.65 - 1.79 (m, 1 H) 2.02 (ddd, 1 H) 3.61 (br. s., 2 H) 4.46 (br. s., 1 H) 6.59 (d, 1 H)

Description 5: 1,1-dimethylethyl (lR,4S,6R)-4-ethynyl-3-azabicyclo[4.1.0]heptane-3- carboxylate (D5)

To a solution of 1,1-dimethylethyl (lR,4S,6R)-4-(2,2-dibromoethenyl)-3- azabicyclo[4.1.0]heptane-3-carboxylate D4 (9 g) in dry THF (215 ml) at -78°C under nitrogen atmosphere, s-BuLi (33.7 ml, 47.2 mmol) was added dropwise over 1 hour. Once the addition was complete, the reaction mixture was left stirring at -78°C for 2 hours, then

150 ml of NH₄C1 saturated solution were added at -78°C and the mixture was allowed to reach room temperature. Then water and Et₂0 were added and phases were separated.

Organic phase was washed with brine, dried over sodium sulphate, filtered and concentrated under reduced pressure. Crude was purified by flash chromatography on silica gel (lOOg SNAP, eluentCy to Cy/EtOAc 9: 1 in 7CV) affording the title compound (4.7 g). The latter was again purified by flash chromatography on silica gel (SNAP lOOg, eluentCy to

Cy/EtOAc 9: 1 in 15CV) affording the title compound D5 (3.98 g).

UPLC (Acid GEN_QC_SS) rt = 0.92 minutes, peak observed: 166 [(M+1-C(CH₃)₃]

Ci₃Hi₉N0₂ requires: 221.

1H NMR (500 MHz, DMSO-i¾) δ ppm -0.24 - -0.09 (m, 1 H) 0.55 - 0.76 (m, 1 H) 0.84 -

1.13 (m, 2 H) 1.38 (s, 9 H) 1.63 - 1.82 (m, 1 H) 1.89 - 2.15 (m, 1 H) 3.19 - 3.61 (m, 1 H)

3.60 - 3.88 (m, 2 H) 4.54 - 4.94 (m, 1 H)

Description 6 : 1,1-dimethylethyl (lR,4S,6R)-4-[(E/Z)-2-(4,4,5,5-tetramethyl-l,3,2- dioxaborolan-2-yl)ethenyl]-3-azabicyclo[4.1.0]heptane-3-carboxylate (D6)

A solution of 1,1-dimethylethyl (lR,4S,6R)-4-ethynyl-3-azabicyclo[4.1.0]heptane-3- carboxylate D5 (500 mg) and 4,4,5, 5-tetramethyl-l,3,2-dioxaborolane (0.984 ml, 6.78 mmol) in dry DCM (12 ml) was degassed with nitrogen stream, then

tris(triphenylphosphine)rhodium(I) chloride (41.8 mg, 0.045 mmol) was added and the mixture was stirred at room temperature for 20 hours. The mixture was quenched with NH₄CI saturated solution and extracted with EtOAc. Organic phase was dried over Na₂S0₄, filtered and concentrated under reduced pressure. Crude was purified by Flash

chromatography on silica gel (Biotage SP1, SNAP 25 g, eluentCy to Cy/EtOAc 9: 1) affording the title compound D6 (162 mg).

UPLC (Acid GEN_QC_SS): rt = 1.07 minutes, peak observed: 350 (M+l). Ci₉H₃₂BN0₄ requires 349.

Description 7: (2S)-2-amino-4-penten-l-ol (D7)

In a 20 L reactor, to a suspension of (2S)-2-amino-4-pentenoic acid (available from Sigma - Aldrich #285013) (200 g, 1319 mmol) in THF dry (3200 ml) stirred under nitrogen at 0 °C was added a solution of LiAlH₄ (1600 ml, 1600 mmol) 1 M in THF dropwise in 1.5 hours (mantaining internal temperature between 0 °C and 5 °C). The reaction mixture was stirred at 25 °C for 2 hours (white suspension). The check by TLC (DCM/MeOH 1/1, AcOH 0.5% ninhidrine) showed reaction to be completed. The reaction mixture was cooled to 0 °C and was quenched by adding in sequence: 60.7 ml of water (1 ml H₂0 x 1 g of L1AIH₄) + 60.7 ml of NaOH 1 N (1 ml NaOH 1M x 1 g of L1AIH₄) + 182 ml of water (3 ml H₂0 x 1 g of LiAlFLi). The suspension was stirred at room temperature for 1 hour then the precipitate was filtered over sodium sulphate (gooch n3) and washed with Et₂0 (6 L) and DCM (4 L). The solvent was evaporated (temperature bath 30 °C) of the crude title compound D7 (110 g) as pale-orange oil. MS: (ES/+) m/z: 102 (M+l). C₅HnNO requires 101. 1H NMR (400 MHz, DMSO-d₆) δ ppm 1.39 (br. s, 2 H) 1.81 - 1.96 (m, 1 H) 2.06 - 2.19 (m, 1 H) 2.59 - 2.73 (m, 1 H) 3.14 (dd, 1 H) 3.26 (dd, 1 H) 4.48 (br. s, 1 H) 4.91 - 5.09 (m, 2 H) 5.71 - 5.92 (m, 1 H)

Description 8: 1,1-dimethylethyl (2-{[(lS)-l-(hydroxymethyl)-3-buten-l-yl]amino}-2- oxoethyl)carbamate (non-preferred name) (D8)

In a 5 L reactor, to a solution of (2S)-2-amino-4-penten-l-ol D7 (110 g of the crude title compound prepared in the description D7) in THF (660 ml) and MeOH (440 ml) stirred at 0 °C (+5 °C internal) was added triethylamine (182 ml, 1305 mmol) and 2,5-dioxo-l- pyrrolidinyl N-{[(l,l-dimethylethyl)oxy]carbonyl}glycinate (available from Sigma -Aldrich #15423) (237 g, 870 mmol) portionwise over 15 min. The reaction mixture was stirred at 2 °C (internal temperature) for 3 hours. TLC check (TLC- H₂, DCM/MeOH 95/5, potassium permanganate) showed residual starting material. Further 2,5-dioxo-l -pyrrolidinyl N-{[(1,1- dimethylethyl)oxy]carbonyl}glycinate (60 g, 220 mmol) was added and the mixture stirred at 2 °C for 1 hour. TLC check (TLC- H₂, DCM/MeOH 95/5, potassium permanganate) showed residual starting material. Further 2, 5-dioxo-l -pyrrolidinyl N-{[(1,1- dimethylethyl)oxy]carbonyl}glycinate (40 g, 146 mmol) was added and the mixture stirred at 2 °C for 1 hours. TLC check (TLC- H₂, DCM/MeOH 95/5, potassium permanganate) showed residual starting material but the work-up was carried out. The reaction mixture was poured into aqueous saturated solution of H₄CI (3400 ml) and EtOAc (1375 ml), then the phases were separated and the aqueous layer was back-extracted with EtOAc (1375 ml). The combined organic layers were washed with NaHC0₃ aqueous saturated solution (1031 ml) dried (Na₂S0₄) and evaporated to give crude material (268 g, deep brown). This residue was triturated with Et₂0 (687 ml) for 1 hour at 25 °C. The solid was filtered (gooch n3), washed with Et₂0 (200 ml) and dried under vacuum to give the title compound D8 (87 g) as pale brown solid. Mother liquors (deep brown) were evaporated and the residue

chromatographed (Biotage 75 L, silica column, eluting with DCM/MeOH 98/2, 95/5) to give (34 g) of residual brown product that was triturated with Et₂0 (200 ml). The solid was filtered, washed with Et₂0 and dried under vacuum to give a further batch of the title compound D8 (26 g) as pale brown solid. MS: (ES/+) m/z: 259 (M+l). Ci₂H₂₂N₂0₄ requires 258. 1H MR (400 MHz, CDC1₃) δ ppm 1.47 (s, 9 H) 2.22 - 2.43 (m, 2 H) 2.68 - 2.83 (m, 1 H) 3.50 - 3.86 (m, 4 H) 3.94 - 4.09 (m, 1 H) 5.00 - 5.25 (m, 3 H) 5.64 - 5.89 (m, 1 H) 6.17 - 6.44 (m, 1 H) Description 9: 1,1-dimethylethyl {2-[(4S)-2,2-dimethyl-4-(2-propen-l-yl)-l,3- oxazolidin-3-yl]-2-oxoethyl}carbamate (non-preferred name) (D9)

To a suspension of 1,1-dimethylethyl (2-{[(l S)-l-(hydroxymethyl)-3-buten-l-yl]amino}-2- oxoethyl)carbamate D8 (37 g) in toluene (370 ml) stirred at 25 °C were added 2,2- bis(methyloxy)propane (370 ml, 3020 mmol) and p-toluenesulfonic acid monohydrate (3.7 g, 19.45 mmol). The reaction mixture was stirred at reflux (85 °C internal, oil bath 105 °C) for 1.5 hour (clear solution). The check by TLC (DCM/MeOH 95/5) showed the reaction to be completed. The solvent was evaporated to obtain a brown oil that was chromatographed (Biotage 75 L, silica, eluting with Cy/EtOAc 8/2, 7/3) to give the title compound D9 (30 g) as yellow oil. UPLC (Acid GEN QC): rt = 0.69 minutes, peak observed: 299 (M+l).

C₁₅H₂₆N₂O₄ requires 298. 1H MR (400 MHz, CDC1₃) δ ppm 1.46 (s, 9 H) 1.54 (s, 3 H) 1.67 (s, 3 H) 2.30 - 2.49 (m, 2 H) 3.71 - 4.05 (m, 5 H) 5.04 - 5.22 (m, 2 H) 5.37 - 5.52 (m, 1 H) 5.65 - 5.81 (m, 1 H)

Description 10: trifluoromethanesulfonic acid - {2-[(4S)-2,2-dimethyl-4-(2-propen-l- yl)-l,3-oxazolidin-3-yl]-2-oxoethyl}amine (1:1) (D10)

To a solution of 1,1 -dimethyl ethyl {2-[(4S)-2,2-dimethyl-4-(2-propen-l-yl)-l,3-oxazolidin- 3-yl]-2-oxoethyl}carbamate D9 (28.67 g) in DCM (300 ml) 2,6-dimethylpyridine (27.9 ml, 240 mmol) was added followed by trimethylsilyl trifluoromethanesulfonate (34.7 ml, 192 mmol) the mixture was stirred at room temperature for 30 min. The reaction was quenched with 2 ml of water and the solvent was removed under reduced pressure, the residue was charged on a Biotage 75 L column eluting with [DCM/MeOH 100:0 then 98:2 then 96:4 then 85: 15]. Evaporation of the solvent gave: the title compound D10 (21 g). UPLC (Acid FINAL QC): rt = 0.36 minutes, peak observed: 199 (M+l - CHF₃O₃S)

CioHi₈N₂0₂-CHF₃0₃S requires 348. 1H MR (400 MHz, DMSO-d₆) δ ppm 1.40 (s, 3 H), 1.50 (s, 3 H), 2.17-2.43 1.40 (m, 2 H), 3.68-3.98 (m, 4 H), 3.99-4.09 (m, 1 H), 4.83-5.40 (m, 2 H), 5.58-5.97 (m, 1 H), 7.63-8.36 (br.s., 2 H)

Description 11 : (4S)-3-(diazoacetyl)-2,2-dimethyl-4-(2-propen-l-yl)-l,3-oxazolidine

{2-[(4S)-2,2-dimethyl-4-(2-propen-l-yl)-l,3-oxazolidin-3-yl]-2-oxoethyl}amine

trifluoromethansulfonate D10 (67.0 g) was dissolved in DCM (670 ml) and pH = 5 Buffer solution (670 ml) and cooled to 2 °C (internal). Sodium nitrite (26.5 g, 385 mmol) dissolved in water (134 ml) was added dropwise to the reaction mixture stirred at 2 °C over 30 min. The reaction mixture was stirred at 3 °C for 2.5 hours. Phases were separated. Water phase was back-extracted with DCM (1 x 670 ml, 1 x 335 ml). The combined organic layers, dried (Na₂S0₄), were evaporated (bath temperature 30 °C) to give 43 g of crude product. This crude was purified over silica pad [(230-400 Mesh) eluting with Cy/EtOAc 8/2, 7/3, 6/4] to give the title compound Dll (36.58 g) as pale yellow oil. UPLC (Acid GEN QC): rt = 0.59 minutes, peak observed: 210 (M+l) C10H15N3O2 requires 209. 1H

MR (400 MHz, CDC1₃) δ ppm 1.58 (s, 3 H) 1.69 (s, 3 H) 2.25 - 2.50 (m, 2 H) 3.43 - 3.70 (m, 1 H) 3.82 - 4.01 (m, 2 H) 4.84 (s, 1 H) 5.09 - 5.24 (m, 2 H) 5.63 - 5.84 (m, 1 H)

Description 12: (5aS,6aS,7aS)-3,3-dimethylhexahydro-5H- cyclopropa[</|[l,3]oxazolo[3,4- ]pyridin-5-one and (5aR,6aR,7aS)-3,3- dimethylhexahydro-5H-cyclopropa [d\ [1 ,3] oxazolo [3,4- ] pyridin-5-one (D12A syn D12B anti)

A syn B anti

(4S)-3-(diazoacetyl)-2,2-dimethyl-4-(2-propen-l-yl)-l,3-oxazolidine Dll (36.5 g) dissolved in DCM (365 ml) was added dropwise at 25 °C to a suspension of rhodium(II) acetate dimer (3.85 g, 8.72 mmol) in DCM (183 ml) over 2.5 hours. The resulting mixture was stirred at 25 °C for 30 minutes. From TLC (Cy/ EtOAc 1/1): no more starting material. The mixture was filtered (gooch n 3), concentrated and chromatographed twice (over silica 230-400 Mesh, eluting with Cy/ EtOAc 7/3, 6/4) to give three fractions that after trituration with n- heptane (40 ml, for each fraction) gave the following three batches:

D12B D12A 95:3 (10.3 g, anti as major isomer anti/syn 95/3) HPLC (walk up): rtl = 3.09 rt2 = 3.14 minutes;

D12A D12B 31:68 (4.47 g, anti/syn roughly 31/68) HPLC (walk up): rtl = 3.05 rt2 = 3.11 minutes;

D12A D12B (10.5 g, D 12A syn as major isomer). HPLC (walk up): rtl = 3.08 rt2 = 3.16 minutes. 1H MR (500 MHz, CDC1₃) δ ppm 3.87 - 4.02 (m, 2 H), 3.32 (t, 1 H), 2.29 - 2.38 (m, 1 H), 1.57 (s, 3 H), 1.45 - 1.51 (m, 1 H), 1.43 (s, 3 H), 1.36 - 1.42 (m, 1 H), 1.12 - 1.20 (m, 1 H), 1.06 - 1.12 (m, 0 H), 0.45 - 0.54 (m, 1 H)

662 mg of this third batch of D12A D12B were taken and purified by flash chromatography (Snap-50 g silica gel column, EtOAc /Cy from 100 % Cy to 30:70). From this purification it was obtained a batch of almost pure cis isomer (the title compound D12A) (298 mg) as white solid, and a 347g batch of a mixture of cis/ trans isomers (75/25) as a colourless oil. UPLC (Basic GEN QC): rt = 0.48 minutes, peak observed: 182 (M+l). Ci₀Hi₅NO₂ requires 181. 1H NMR (400 MHz, CDC1₃) δ ppm 3.98 - 4.10 (m, 2 H) 3.36 - 3.45 (m, 1 H) 2.37 - 2.47 (m, 1 H) 1.66 (s, 3 H) 1.53 - 1.61 (m, 1 H) 1.52 (s, 3 H) 1.42 - 1.50 (m, 1 H) 1.14 - 1.29 (m, 2 H) 0.59 (m, 1 H)

Description 13: (lS,4S,6S)-4-(hydroxymethyl)-3-azabicyclo[4.1.0]heptan-2-one (D13)

(5aS,6aS,7aS)-3,3-dimethylhexahydro-5H-cyclopropa[d][l,3]oxazolo[3,4-a]pyridin-5-one D12 (3.56 g) was dissolved in HCl (25 ml, 150 mmol)(6 M in water) into a 250 ml-round bottomed flask and the mixture was stirred at 40 °C: after 4 hours the reaction was complete. The solvent was evaporated at reduced pressure using a rotavapor (bath temperature: 40 °C). The oily residue was stripped with toluene and the residue dried under high vacuum for 3 hours, obtaining the title compound D13 as white solid (2.843 g). UPLC (Acid IPQC): rt = 0.31 minutes, peak observed: 142 (M+l). C₇HnN0₂ requires 141. 1H NMR (500 MHz, DMSO-i¾) d ppm 0.56 - 0.68 (m, 1 H) 0.93 - 1.05 (m, 1 H) 1.30 - 1.39 (m, 1 H) 1.39 - 1.48 (m, 1 H) 1.57 - 1.67 (m, 1 H) 1.98 - 2.09 (m, 1 H) 3.17 - 3.29 (m, 2 H) 3.31 - 3.40 (m, 1 H) 6.89 - 7.13 (m, 1 H)

Description 14: 1,1-dimethylethyl (lS,4S,6S)-4-(hydroxymethyl)-3- azabicyclo[4.1.0]heptane-3-carboxylate (D14)

(lS,4S,6S)-4-(hydroxymethyl)-3-azabicyclo[4.1.0]heptan-2-one D13 (3.839 g) was suspended in THF (40 ml) then BH₃.THF (1 M THF solution, 136 ml, 136 mmol) was added slowly (over 5 minutes) and the resulting mixture stirred at reflux for 2 hours. The mixture was cooled to room temperature and then to 0 °C using an ice/water bath. MeOH (25 ml) was slowly added and, when the gas evolution stopped, HCl (3 M water solution, 140 ml, 420 mmol) was slowly added and the resulting mixture was stirred again at 85 °C for 1 hour. The mixture was cooled again to room temperature.

A second reaction mixture was prepared: (lS,4S,6S)-4-(hydroxymethyl)-3- azabicyclo[4.1.0]heptan-2-one D13 (100 mg) was suspended in THF (0.5 mL), then

BH₃.THF (3.6 mL, 3.60 mmol) was added slowly (over 1 minute) and the resulting mixture stirred at reflux for 2 hours. This second mixture was chilled to room temperature, then HCl (3.6 mL, 10.80 mmol) was slowly added and the resulting mixture was stirred again at 75°C for 1 hour. This mixture was chilled again to room temperature and then it was added to the first mixture to form a single mixture.

NaOH (3 M water solution, 140 ml, 420 mmol) was slowly added to the acidic mixture, then additional NaOH (50 ml, 150 mmol) was added in order to get a pH value of about 10. Boc₂0 (7.13 ml, 30.7 mmol) was added dissolved in THF (30 ml) and the resulting biphasic mixture was stirred vigorously at room temperature overnight. New Boc₂0 (4.57 ml, 19.70 mmol) was added dissolved in THF (20 ml) and the mixture stirred vigorously at room temperature for 1.5 hours. EtOAc (100 ml) was added to the mixture and the phases were separated. The water phase was extracted with EtOAc (3 x 100 mis) and all the organic fractions were mixed together. The so obtained organic solution was washed with brine (3 x 150 mis), dried over Na₂S0₄ and evaporated at reduced pressure, obtaining the crude target material as pale yellow oil (14 g). This material was purified by Biotage (Snap-340 g silica gel column, from pure Cy to EtOAc /Cy 70:30). It was obtained the title compound D14 (5.695 g) as colourless oil. MS: (ES/+) m/z: 228 (M+l) 128 (M+l-Boc). Ci₂H₂iN0₃ requires 227. 1H MR (500 MHz, DMSO-d₆) δ ppm 4.43 (t, 1 H), 4.00 - 4.20 (m, 1 H), 3.34 - 3.45 (m, 1 H), 3.25 - 3.31 (m, 2 H), 2.10 - 2.23 (m, 1 H), 2.00 - 2.10 (m, 1 H), 1.30 (s, 9 H), 0.86 - 0.99 (m, 2 H), 0.66 - 0.77 (m, 1 H), 0.51 - 0.61 (m, 1 H), -0.04 - 0.05 (m, 1 H)

Description 15: 1,1-dimethylethyl (lS,4S,6S)-4-formyl-3-azabicyclo[4.1.0]heptane-3- carboxylate (D15)

Dess-Martin periodinane (1866 mg, 4.40 mmol) was added to a solution of 1,1- dimethylethyl (1 S,4S,6S)-4-(hydroxymethyl)-3-azabicyclo[4.1.0]heptane-3-carboxylate D14 (1000 mg, 4.40 mmol) in DCM (20 ml). After 3 hours at 23 °C a saturated solution of Na₂S₂0₃ (35 ml) was added to the reaction mixture and stirred for 1 hour.

The aqueous phase was back extracted with DCM (3 x 10 ml), organics were collected, dried (Na₂S0₄), filtered and evaporated under reduced pressure.

The crude obtained was purified by silica gel chromatography (SNAP KP-Sil 25g; eluted with Cy/EtOAc 5 CV from 100% Cy to 95/4, 5 CV 95/5).

Evaporated fractions gave the title compound D15 as yellowish oil (610 mg).

MS: (ES/+) m/z: 170 [M+1-C(CH₃)₃]

Description 16: 1,1-dimethylethyl (lS,4S,6S)-4-(2,2-dibromoethenyl)-3- azabicyclo [4.1.0] heptane-3-carboxylate (Dl 6)

To a suspension of triphenylphosphine (2841 mg, 10.83 mmol) and CBr₄ (1796 mg, 5. mmol) in DCM (11 ml) was added dropwise at 0 °C a solution of 1,1-dimethylethyl (lS,4S,6S)-4-formyl-3-azabicyclo[4.1.0]heptane-3-carboxylate D15 (610 mg) in DCM (9 ml). The resulting mixture was stirred at 0 °C for 30 minutes.

A saturated solution of NaHC0₃ (40 ml) was added and the phase separated. The aqueous phase was back extracted with DCM (2 x 5 ml) and the collected organic layers were dried (Na₂S0₄), filtered and evaporated under reduced pressure.

The yellow solid obtained was purified by silica gel chromatography (SNAP KP-Sil 50g; eluted with Cy/EtOAc, 5 CV from 100% Cy to 95/5, 5 CV 95/5).

It was obtained the title compound D16 as white solid (700 mg).

UPLC (Basic GEN QC): rt = 1.11 minutes peak observed: 382 (M+l) Ci₃Hi₉Br₂N0₂ requires: 381.

1H NMR (400 MHz, CHLOROFORM-^ δ ppm 0.15 (q, 1 H) 0.76 - 0.85 (m, 1 H) 0.85 - 1.05 (m, 2 H) 1.10 - 1.24 (m, 1 H) 1.48 (s, 9 H) 2.23 - 2.52 (m, 2 H) 4.13 - 4.33 (m, 1 H) 4.34 - 4.53 (m, 1 H) 6.27 (d, 1 H) Description 17: 1,1-dimethylethyl (lS,4S,6S)-4-ethynyl-3-azab ic clo [4.1.0] heptane-3- carboxylate (D17)

A solution of 1,1-dimethylethyl (l S,4S,6S)-4-(2,2-dibromoethenyl)-3- azabicyclo[4.1.0]heptane-3-carboxylate D16 (700 mg) in dry THF (18 ml) was cooled to - 78 °C under nitrogen atmosphere and treated with sec-butyllithium (2.76 ml, 3.86 mmol) dropwise over 45 minutes. The resulting solution was stirred at -78 °C for 1 hour.

The reaction mixture was treated with 20 ml of aqueous NH₄C1 saturated solution, warmed to room temperature, diluted with 50 ml of Et₂0 and the layers were separated.

The organic one was washed with 10 ml of brine, dried over Na₂S0₄ anhydrous, filtered and concentrated under vacuum to dryness.

The resulting orange oil was purified by silica gel chromatography (SNAP KP-Sil 50 g; eluted with Cy/EtOAc 10 CV from 100% Cy to 95/5, 7 CV 95/5).

Evaporated fractions gave the title compound D17 as colourless oil (345 mg).

1H NMR (400 MHz, CHLOROFORM-^ δ ppm 0.63 - 0.77 (m, 2 H) 0.84 - 0.98 (m, 1 H) 1.11 - 1.25 (m, 1 H) 1.49 (s, 9 H) 1.62 - 1.88 (m, 1 H) 2.24 (d, 1 H) 2.28 - 2.39 (m, 1 H)

2.83 - 3.10 (m, 1 H) 4.21 - 4.34 (m, 1 H) 4.71 (br. s., 1 H)

Description 18: 1,1-dimethylethyl (lS,4S,6S)-4-{[5-(trifluoromethyl)-2- pyrazinyl]ethynyl}-3-azabic clo [4.1.0] heptane-3-carboxylate (Dl 8)

1,1 -dimethyl ethyl (lS,4S,6S)-4-ethynyl-3-azabicyclo[4.1.0]heptane-3-carboxylate D17 (150 mg), 2-bromo-5-(trifluoromethyl)pyrazine (154 mg, 0.678 mmol), DIPEA (0.592 ml, 3.39 mmol), Pd[(C₆H₅)₃P]4 (78 mg, 0.068 mmol) and copper(I) iodide (25.8 mg, 0.136 mmol) were collected together and dissolved in DMF (5 ml).

The reaction was stirred at 23 °C for 3 hours.

A saturated solution of NaHC0₃ (20 ml) was added and the aqueous layer was back extracted with Et₂0 (3 x 10 ml). The collected organic layers were washed with brine (3 x 5 ml), dried over Na₂S0₄, filtered, and concentrated under vacuum to give the crude product. The crude product was purified by silica gel chromatography (SNAP KP-Sil 25g cartridge; eluted with Cy/EtOAc 5 CV from 100% Cy to 90/10, 5 CV 90/10).

Evaporation of the fractions gave the title compound D18 (140 mg).

UPLC (IPQC): rt = 1.38 minutes, peak observed: 312 [M+l- C(CH₃)₃] Description 19: 1,1-dimethylethyl (lS,4R,6S)-4-{2-[5-(trifluoromethyl)-2- pyrazinyl]ethyl}-3-azabic clo [4.1.0] heptane-3-carboxylate (Dl 9)

To a solution of 1,1-dimethylethyl (lS,4S,6S)-4-{[5-(trifluoromethyl)-2-pyrazinyl]ethynyl}- 3-azabicyclo[4.1.0]heptane-3-carboxylate D18 (140 mg) in dry MeOH (20 ml) at room temperature was added Pd/C (40.6 mg, 0.038 mmol) in one charge. The mixture was stirred under H₂ atmosphere (1 Atm) at room temperature for 2 hours.

The catalyst was filtered off, the solvent was evaporated and the residue was treated with the same procedure above described. The mixture was stirred for additional 1 hour under H₂ atmosphere. The conversion was complete. The catalyst was filtered off, the solvent was evaporated and the residue (145 mg) was purified by flash chromatography (SNAP 10 g, cyclohexane:EtOAc=9: 1). The appropriated fractions were joined and concentrated to obtain the title compound D19 (65 mg).

UPLC (Basic GEN QC Lowgain) : rt = 1.04 minutes, peak observed: 372 (M+l)

Ci₈H₂₄F₃N₃0₂ requires: 371.

Description 20: (lS,4R,6S)-4-{2-[5-(trifluoromethyl)-2-pyrazinyl]ethyl}-3- azabicyclo[4.1.0]heptane (D20)

To a solution of 1,1 -dimethyl ethyl (lS,4R,6S)-4-{2-[5-(trifluoromethyl)-2-pyrazinyl]ethyl}- 3-azabicyclo[4.1.0]heptane-3-carboxylate D19 (65 mg) in DCM (5 ml) at room temperature TFA (1 ml, 12.98 mmol) was added dropwise. The solution was stirred at room temperature for 30 minutes. The volatiles were removed under reduced pressure. The residue was loaded onto a SCX cartridge (1 g, eluting with MeOH and ammonia (2.0 M in MeOH). The ammoniacal fractions were joined and evaporated to give the title compound D20 (45 mg). UPLC (Basic GEN QC Lowgain) : rt = 0.78 minutes, peak observed: 272 (M+l)

C13HK5F3N3 requires: 271.

Description 21 : 1,1-dimethylethyl (lR,4S,6R)-4-{[5-(trifluoromethyl)-2- pyridinyl] ethynyl}-3-azabic clo [4.1.0] heptane-3-carboxylate (D21)

1,1-dimethylethyl (lR,4S,6R)-4-ethynyl-3-azabicyclo[4.1.0]heptane-3-carboxylate D5 (170 mg), 2-chloro-5-(trifluoromethyl)pyridine (139 mg, 0.768 mmol), DIPEA (0.671 ml, 3.84 mmol), Pd[(C₆H₅)₃P]4 (89 mg, 0.077 mmol) and copper (I) iodide (29.3 mg, 0.154 mmol) were collected together and dissolved in DMF (7.5 ml). The reaction was stirred at 23 °C for 3 hours.

A saturated solution of NaHC0₃ (20 ml) was added and the aqueous layer was back extracted with Et₂0 (3 x 10 ml). The collected organic layers were washed with brine (3 x 5 ml), dried over Na₂S0₄, filtered and concentrated under vacuum to give the crude product. This was purified by silica gel chromatography (SNAP KP-Sil 25 g cartridge; eluted with Cy/EtOAc 5 CV from 100% Cy to 90/10, 5 CV 90/10). Evaporation of the fractions gave the title compound D21 (36 mg), which was used without further purification.

UPLC (IPQC): rt = 1.45 minutes, peak observed: 367 (M+l), 311 [M+1-C(CH₃)₃].

Ci H₂iF₃N₂0₂ requires 366.

Description 22: 1,1-dimethylethyl (lR,4S,6R)-4-{[5-(trifluoromethyl)-2- pyridinyl] ethynyl}-3-azabic clo [4.1.0] heptane-3-carboxylate (D22)

A suspension of 1,1-dimethylethyl (lR,4S,6R)-4-{[5-(trifluoromethyl)-2- pyridinyl]ethynyl}-3-azabicyclo[4.1.0]heptane-3-carboxylate D21 (36 mg) and Pd/C (10.46 mg, 9.83 μηιοΐ) in MeOH (5 ml) was stirred in hydrogen atmosphere for 5 hours. The reaction mixture was filtered through a Celite pad and the solvent removed under vacuum. The title compound D22 (22 mg) was used as a crude oil.

UPLC (TPQC): rt = 1.49 minutes, peak observed: 371 (M+l), 315 [M+1-C(CH₃)₃]. 271 (M+l-Boc). Ci9H₂5F₃N₂02 requires 370.

Description 23: (lR,4R,6R)-4-{2-[5-(trifluoromethyl)-2-pyridinyl]ethyl}-3- azabicyclo[4.1.0]heptane (D23)

1,1 -dimethyl ethyl (lR,4R,6R)-4-{2-[5-(trifluoromethyl)-2-pyridinyl]ethyl}-3- azabicyclo[4.1.0]heptane-3-carboxylate D22 (22 mg) was dissolved in DCM (0.6 ml) and TFA (4.58 μΐ, 0.059 mmol) was added.

After 1 hour the volatiles were removed under vacuum and the brown oil obtained was charged on cationic exchange cartridge (SCX lg; washed with 30 ml of MeOH, eluted with 9 ml of 2M H₃/MeOH). The evaporation of ammoniac fraction gave the title compound D23 as yellowish oil (13 mg).

UPLC (IPQC): rt = 0.64 minutes, peak observed: 271 (M+l). Ci₄Hi₇F₃N₂ requires 270.

Description 24: 1,1-dimethylethyl (lR,4S,6R)-4-{[3-(trifluoromethyl)-2- pyridinyl]ethynyl}-3-azabic clo [4.1.0] heptane-3-carboxylate (D24)

In a microwave vial 1,1-dimethylethyl (lR,4S,6R)-4-ethynyl-3-azabicyclo[4.1.0]heptane-3- carboxylate D5 (250 mg), 2-chloro-3-(trifluoromethyl)pyridine (246 mg, 1.356 mmol), Cs₂C0₃ (368 mg, 1.130 mmol), bis(triphenylphosphine)palladium(II) chloride (15.86 mg, 0.023 mmol), tri-t-butylphosphine (10.96 μΐ, 0.045 mmol) and DBU (14 μΐ, 0.093 mmol) were dissolved in DMF (4 ml). The vial was sealed under nitrogen and the mixture was irradiated for 10 minutes at 150 °C.

The reaction mixture was cooled to 23 °C, diluted with EtOAc (30 ml) and filtered through a Celite pad. The filtrate was washed with brine (3 x 20 ml) and the combined aqueous layers were back extracted with EtOAc (2 x 5 ml). Organic layers were dried (Na₂S0₄), filtered and evaporated.

The brown oil obtained was purified by column chromatography (SNAP KP-Sil 25g; eluted with Cy/EtOAc 4CV from 100% Cy to 80/20, 6CV 80/20). Evaporated fractions gave a yellow oil (130 mg), containing desired compound with coloured impurities. It was charged on silica gel column (SNAP KP-Sil lOg) and eluted with DCM/EtOAc 10CV from 100% DCM to 90/10, 5CV 90/10.

Evaporated fractions gave the title compound D24 (115 mg).

UPLC (Basic GEN QC) rtl = 1.0 minutes rt2: 1.04 minutes (rotamers present) peaks observed: 367 (M+l) 311 [M+1-C(CH₃)₃] 267 (M+l- Boc) Ci₉H₂iF₃N₂0₂ requires 366. 1H NMR (400 MHz, CHLOROFORM-^ δ ppm 0.03 (br. s., 1 H) 0.77 (br. s., 1 H) 0.94 - 1.24 (m, 2 H) 1.24 - 1.36 (m, 1 H) 1.39 - 1.53 (m, 9 H) 1.91 (br. s., 1 H) 2.28 (d, 1 H) 3.74 (br. s., 1 H) 5.27 (br. s., 1 H) 7.38 (dd, 1 H) 7.98 (d, 1 H) 8.69 - 8.81 (m, 1 H)

Description 25: 1,1-dimethylethyl (lR,4R,6R)-4-{2-[3-(trifluoromethyl)-2- pyridinyl] ethyl}-3-azabic clo [4.1.0] heptane-3-carboxylate (D25)

1,1-dimethylethyl (lR,4S,6R)-4-{[3-(trifluoromethyl)-2-pyridinyl]ethynyl}-3- azabicyclo[4.1.0]heptane-3-carboxylate D24 (115 mg) was dissolved in MeOH (8 ml), Pd/C (33.4 mg, 0.031 mmol) was added and the resulting suspension was stirred under hydrogen atmosphere. After 2 hours the reaction mixture was filtered and the solvent evaporated to dryness.

It was obtained the title compound D25 as colourless oil (115 mg).

UPLC (IPQC) rt = 1.36 minutes peak observed: 371 (M+l) 315 [M+l- C(CH₃)₃] 271 (M+l- Boc) Ci₉H₂₅F₃N₂0₂ requires 370.

Description 26: (lR,4R,6R)-4-{2-[3-(trifluoromethyl)-2-pyridinyl]ethyl}-3- azabicyclo[4.1.0]heptane (D26)

To a solution of 1,1-dimethylethyl (lR,4R,6R)-4-{2-[3-(trifluoromethyl)-2-pyridinyl]ethyl}- 3-azabicyclo[4.1.0]heptane-3-carboxylate D25 (115 mg) in DCM (3 ml) was added TFA (0.75 ml, 9.73 mmol). After 30 minutes the solvent was removed under reduced pressure and the yellow oil obtained was charged on a SCX (2 g, washed with 40 ml of MeOH and eluted with 10 ml of 2M NH₃/MeOH).

The ammoniac fraction was evaporated to dryness. A yellow oil was obtained containing title compound and other impurities (65 mg).

This oil was purified by column chromatography (SNAP KP-NH 1 lg; eluted with

Cy/iPrOH 3CV from 100% Cy to 99/1, 5CV 99/1).

Evaporated fraction gave a yellowish oil, resulted to be the title compound D26 (62 mg). UPLC (Basic GEN QC) rt = 0.76 minutes peak observed: 271 (M+l) C14H17F3N2 requires 270.

1H MR (500 MHz, DMSO-i¾) δ ppm 0.11 - 0.21 (m, 1 H) 0.50 - 0.59 (m, 1 H) 0.88 - 1.02 (m, 2 H) 1.34 - 1.45 (m, 1 H) 1.57 - 1.71 (m, 2 H) 1.71 - 1.79 (m, 1 H) 2.08 - 2.18 (m, 1 H) 2.56 - 2.63 (m, 1 H) 2.75 - 2.88 (m, 1 H) 2.95 - 3.06 (m, 1 H) 3.26 - 3.37 (m, 1 H) 7.42 - 7.46 (m, 1 H) 8.09 (d, 1 H) 8.77 (d, 1 H)

Description 27: 1,1-dimethylethyl (lR,4S,6R)-4-{[5-(trifluoromethyl)-2- pyrazinyl] ethynyl}-3-azabic clo [4.1.0] heptane-3-carboxylate (D27)

bis(triphenylphosphine)palladium(II) chloride (21.40 mg, 0.030 mmol), triphenylphosphine (15.99 mg, 0.061 mmol), TEA (4.5 ml, 32.3 mmol), 2-bromo-5-(trifluoromethyl)pyrazine (346 mg, 1.524 mmol) and copper(I) iodide (11.61 mg, 0.061 mmol) were collected together in a round bottomed flask. The mixture was stirred for 30 minutes and then 1,1- dimethylethyl (lR,4S,6R)-4-ethynyl-3-azabicyclo[4.1.0]heptane-3-carboxylate D5 (337 mg) was added. The reaction was stirred at room temperature for 2 hours.

A saturated solution of H₄CI (10 ml) was added and the aqueous layer was back extracted with diethyl ether (3 x 10 ml). The collected organic layers were washed with brine (3 x 5 ml), dried over Na₂S0₄, filtered, and concentrated under vacuum to give the crude product. The crude product was purified by silica gel chromatography (SNAP KP-Sil 25g cartridge; eluted with Cy/EtOAc 5CV from 100% Cy to 90/10, 5 CV 90/10).

Collection and evaporation of the fractions gave the title compound D27 (300 mg).

UPLC (GEN_QC_SS) rt = 1.02 minutes, peak observed: 312 [M-C(CH₃)₃] Ci₈H₂₀F₃N₃O₂ requires: 368.

Description 28: 1,1-dimethylethyl (lR,4R,6R)-4-{2-[5-(trifluoromethyl)-2- pyrazinyl]ethyl}-3-azabic clo [4.1.0] heptane-3-carboxylate (D28)

1 , 1 -dimethylethyl ( 1R,4 S,6R)-4- { [5 -(trifluoromethyl)-2-pyrazinyl] ethynyl } -3 - azabicyclo[4.1.0]heptane-3-carboxylate D27 (300 mg) was dissolved in MeOH (20 ml) then Pd/C (8.69 mg, 0.082 mmol) was added and the reaction was hydrogenated at atmosferic pressure of hydrogen at room temperature for 3 hours. The catalyst was filtered through a Celite pad, and the methanolic phase was evaporated under vacuum to give the title compound D28 (220 mg), which was used for next step without any purification.

UPLC (Basic GEN QC) rt = 1.06 minutes, peak observed: 372 (M+l) 316 [M+l- C(CH₃)₃] Ci₈H₂₄F₃N₃0₂ requires: 371. Description 29: (lR,4R,6R)-4-{2-[5-(trifluoromethyl)-2-pyrazinyl]ethyl}-3- azabicyclo[4.1.0]heptane (D29)

To a solution of 1,1 -dimethyl ethyl (lR,4R,6R)-4-{2-[5-(trifluoromethyl)-2- pyrazinyl]ethyl}-3-azabicyclo[4.1.0]heptane-3-carboxylate D28 (220 mg) in DCM (5 ml), TFA (2.5 ml, 32.4 mmol) was added dropwise. The mixture was left stirring at room temperature for 1 hour. Solvent was evaporated in vacuum and the crude was purified by SCX using MeOH 100% to MeOH/NH₃ 2M. It was recovered the title compound D29 (152 mg).

UPLC (Final QC) rt = 0.46 minutes, peak observed: 272 (M+l) Ci₃Hi₆F₃N₃ requires: 271.

Description 30: 1,1-dimethylethyl (lR,4S,6R)-4-{(E/Z)-2-[4-(trifluoromethyl)-2- pyridinyl] ethenyl}-3-azabic clo [4.1.0] heptane-3-carboxylatecarboxylate (D30)

To a degassed solution of 1,1-dimethylethyl (lR,4S,6R)-4-[(E/Z)-2-(4,4,5,5-tetramethyl- l,3,2-dioxaborolan-2-yl)ethenyl]-3-azabicyclo[4.1.0]heptane-3-carboxylate D6 (100 mg) and 2-chloro-4-(trifluoromethyl)pyridine (62.4 mg, 0.344 mmol) in DME (3 ml) and sodium carbonate 2M solution (1 ml, 0.286 mmol), bis(triphenylphosphine)palladium(II) chloride (20.10 mg, 0.029 mmol) was added and the mixture was heated to 90°C and stirred at that temperature for 1 hour. The mixture was cooled down to room temperature then partitioned between water and EtOAc. Organic phase was dried over sodium sulphate, filtered and concentrated under reduced pressure. Crude was purified by Flash Chromatography on silica gel (Biotage SP1, SNAPlOg, eluentCy to Cy/EtOAc 8:2) affording the title compound D30 (51 mg).

UPLC (GEN QC SS): rt = 1.03 min, peak observed: 369 (M+l). Ci₉H₂₃F₃N₂0₂ requires 368.

Description 31: 1,1-dimethylethyl (lR,4R,6R)-4-{2-[4-(trifluoromethyl)-2- pyridinyl] ethyl}-3-azabic clo [4.1.0] heptane-3-carboxylate (D31)

1,1 -dimethyl ethyl (lR,4S,6R)-4-{(E/Z)-2-[4-(trifluoromethyl)-2-pyridinyl]ethenyl}-3- azabicyclo[4.1.0]heptane-3-carboxylate D30 (51 mg) was dissolved in dry MeOH (10 ml) then Pd/C (14.73 mg, 0.014 mmol) was added and the reaction was hydrogenated at atmospheric pressure and at room temperature for 50 minutes. Reaction was gone to completion thus it was filtered over a pad of Celite washing with MeOH. Solvent was eliminated under reduced pressure affording the title compound D31 (48 mg).

UPLC (GEN QC SS): rt = 1.03 min, peak observed: 371 (M+l). C19H25F3N2O2 requires 370.

1H MR (400 MHz, CHLOROFORM-<f) δ ppm 0.01 (q, 1 H) 0.61 - 0.76 (m, 1 H) 0.84 - 1.06 (m, 2 H) 1.31 - 1.55 (m, 9 H) 1.71 - 2.01 (m, 3 H) 2.09 - 2.30 (m, 1 H) 2.71 - 2.91 (m, 2 H) 3.33 (br. s., 1 H) 3.96 (br. s., 1 H) 4.10 (br. s., 1 H) 7.30 - 7.42 (m, 2 H) 8.72 (d, 1 H)

Description 32: 1,1-dimethylethyl (lR,4R,6R)-4-{2-[4-(trifluoromethyl)-2- pyridinyl] ethyl}-3-azabicyclo [4.1.0] heptane-3-carboxylate (D32)

To a solution of 1,1-dimethylethyl (lR,4R,6R)-4-{2-[4-(trifluoromethyl)-2-pyridinyl]ethyl}- 3-azabicyclo[4.1.0]heptane-3-carboxylate D31 (48 mg) in dry DCM (2 ml),TFA (0.5 ml, 6.49 mmol) was added and the mixture was stirred at room temperature for 45 minutes. Reaction was gone to completion thus it was concentrated under reduced pressure, the residue dissolved in MeOH and loaded on a SCX cartridge washing with MeOH and eluting with NH₃ 2M in MeOH affording the title compound D32 (33 mg).

UPLC (GEN_QC_SS): rt = 0.54 min, peak observed: 271 (M+l). Ci₄Hi₇F₃N₂ requires 270. Description 33: 4-(trifluoromethyl)-l,3-thiazol-2-amine (D33)

A solution of 3-bromo-l,l,l-trifluoro-2-propanone (4 g, 20.95 mmol) and thiourea (1.595 g, 20.95 mmol) in EtOH (40 ml) was heated to 70°C and stirred at that temperature for 2 hours. Reaction was gone to completion thus the mixture was cooled down to room temperature, solvent eliminated under reduced pressure and crude was triturated with Et₂0 affording the title compound as hydrochloride salt. The latter was therefore treated with NaHCC saturated solution and extracted with DCM. Organic phase was dried over phase separator filter tube and concentrated under reduced pressure affording the title compound D33 (3.1 g).

UPLC (GEN_QC_SS): rt = 0.58 min, peak observed: 169 (M+l). C₄H₃F₃N₂S requires 168. 1H NMR (400 MHz, CHLOROFORM-^ δ ppm 5.50 (br. s., 2 H) 6.98 (s, 1 H)

Description 34: 2-chloro-4-(trifluoromethyl)-l,3-thiazole (D34)

To a solution of 4-(trifluoromethyl)-l,3-thiazol-2-amine D33 (2.9 g) in dry ACN (35 ml), copper(II) chloride (2.78 g, 20.70 mmol) was added, then 1,1 -dimethyl ethyl nitrite (3.08 ml, 25.9 mmol) was added dropwise (bubbling observed) at room temperature and the mixture was stirred at that temperature for 45 minutes. The mixture was then partitioned between water and Et₂0, organic phase was washed with brine, dried over Na₂S0₄, filtered and concentrated under reduced pressure (desired compound was volatile thus cold bath and minimum pressure 700mBar were used). The resulting solution was then distilled with Claisen apparatus in order to remove Et₂0 and ACN affording the title compound D34 (2-25 g).

1H NMR (400 MHz, CDC1₃) 6(ppm): 7.69 (s, 1 H). Description 35: 1,1-dimethylethyl (lR,4S,6R)-4-{(E/Z)-2-[4-(trifluoromethyl)-l,3- thiazol-2-yl] ethenyl}-3-azabic clo [4.1.0] heptane-3-carboxylate (D35)

To a degassed solution of 1,1-dimethylethyl (lR,4S,6R)-4-[(E/Z)-2-(4,4,5,5-tetramethyl- l,3,2-dioxaborolan-2-yl)ethenyl]-3-azabicyclo[4.1.0]heptane-3-carboxylate D6 (65 mg) and 2-chloro-4-(trifluoromethyl)-l,3-thiazole D34 (84 mg) in DME (3 ml) and sodium carbonate 2M solution (1 ml, 0.186 mmol), bis(triphenylphosphine)palladium(II) chloride (13.06 mg, 0.019 mmol) was added and the mixture was heated to 90°C and stirred at that temperature for 1 hour. The mixture was cooled down to room temperature then partitioned between water and EtOAc. Organic phase was dried over Na₂S0₄, filtered and concentrated under reduced pressure. Crude was purified by Flash Chromatography on silica gel (Biotage SP1, SNAPlOg, eluentCy to Cy/EtOAc 8:2) affording the title compound D35 (41 mg). UPLC (GEN QC SS): rt = 1.07 min, peak observed: 375 (M+l). C₁₇H₂₁F₃N₂O₂S requires 374. Description 36: 1,1-dimethylethyl (lR,4R,6R)-4-{2-[4-(trifluoromethyl)-l,3-thiazol-2- yl] ethyl}-3-azabicyclo [4.1.0] heptane-3-carboxylate (D36)

1 , 1 -dimethyl ethyl (lR,4S,6R)-4-{ (E/Z)-2-[4-(trifluoromethyl)- 1 ,3 -thiazol-2-yl]ethenyl } -3- azabicyclo[4.1.0]heptane-3-carboxylate D35 (41 mg) was dissolved in dry MeOH (10 ml) then Pd/C (11.65 mg, 10.95 μιηοΐ) was added and the reaction was hydrogenated at atmospheric pressure and at room temperature for 2 hours. The catalyst was filtered off over a pad of Celite washing with MeOH then solvent was eliminated under reduced pressure affording the title compound D36 (37 mg).

UPLC (GEN_QC_SS): rt = 1.07 min, peak observed: 377 (M+l). C₁₇H₂₃F₃N₂O₂S requires 376.

Description 37: (lR,4R,6R)-4-{2-[4-(trifluoromethyl)-l,3-thiazol-2-yl]ethyl}-3- azabicyclo[4.1.0]heptane (D37)

To a solution of 1,1-dimethylethyl (lR,4R,6R)-4-{2-[4-(trifluoromethyl)-l,3-thiazol-2- yl]ethyl}-3-azabicyclo[4.1.0]heptane-3-carboxylate D36 (37 mg) in DCM (2 ml),TFA (0.379 ml, 4.91 mmol) was added and the mixture was stirred at room temperature for 45 minutes. Reaction was gone to completion thus it was concentrated under reduced pressure, the residue dissolved in MeOH and loaded on a SCX cartridge washing with MeOH and eluting with ¼ 2M in MeOH affording the title compound D37 (27 mg).

UPLC (GEN_QC_SS): rt = 0.51 min, peak observed: 277 (M+l). C₁₂H₁₅F₃N₂S requires 276. Description 38: 1,1-dimethylethyl (lR,4S,6R)-4-{(E/Z)-2-[2-(trifluoromethyl)-4- pyrimidinyl]ethenyl}-3-azabicyclo [4.1.0] heptane-3-carboxylate (D38)

To a degassed solution of 1,1-dimethylethyl (lR,4S,6R)-4-[(E/Z)-2-(4,4,5,5-tetramethyl- l,3,2-dioxaborolan-2-yl)ethenyl]-3-azabicyclo[4.1.0]heptane-3-carboxylate D6 (90 mg) and 4-chloro-2-(trifluoromethyl)pyrimidine (56.4 mg, 0.309 mmol) in DME (3 ml) and sodium carbonate 2M solution (1 ml, 0.258 mmol), bis(triphenylphosphine)palladium(II) chloride (18.09 mg, 0.026 mmol) was added and the mixture was heated to 90°C and stirred at that temperature for 1 hour. The mixture was cooled down to room temperature then partitioned between water and EtOAc. Organic phase was dried over Na₂S04, filtered and concentrated under reduced pressure. Crude was purified by flash chromatography on silica gel (Biotage SP1, SNAP 10 g, eluen Cy to Cy/EtOAc 8:2) affording the title compound D38 (46 mg). UPLC (GEN QC SS): rt = 1.03 min, peak observed: 370 (M+l). Ci₈H₂₂F₃N₃0₂ requires 369.

Description 39: 1,1-dimethylethyl (lR,4R,6R)-4-{2-[2-(trifluoromethyl)-4- pyrimidinyl] ethyl}-3-azabic clo [4.1.0] heptane-3-carboxylate (D39)

To a solution of 1,1 -dimethyl ethyl (lR,4S,6R)-4-{(E/Z)-2-[2-(trifluoromethyl)-4- pyrimidinyl]ethenyl}-3-azabicyclo[4.1.0]heptane-3-carboxylate D38 (46 mg) in MeOH (8 ml), Lindlar catalyst (26.5 mg, 0.012 mmol) was added and the reaction was hydrogenated at room temperature for 20 hours.

Only starting material was detected thus the mixture was filtered over a pad of Celite washing with MeOH, solvent was eliminated under reduced pressure; the residue was dissolved again in MeOH (8 ml), Pd/C (13.25 mg, 0.012 mmol) was added and the mixture was hydrogenated at room temperature for 20 minutes. The mixture was then filtered over a pad of Celite washing with MeOH affording the title compound D39 (44 mg).

UPLC (GEN QC SS): rt = 1.03 min, peak observed: 372 (M+l). Ci₈H₂₄F₃N₃0₂ requires 371.

Description 40: (lR,4R,6R)-4-{2-[2-(trifluoromethyl)-4-pyrimidinyl]ethyl}-3- azabicyclo[4.1.0]heptane (D40)

To a solution of 1,1 -dimethyl ethyl (lR,4R,6R)-4-{2-[2-(trifluoromethyl)-4- pyrimidinyl]ethyl}-3-azabicyclo[4.1.0]heptane-3-carboxylate D39 (44 mg) in dry DCM (2 ml),TFA (0.456 ml, 5.92 mmol) was added and the mixture was stirred at room temperature for 45 minutes. Reaction was gone to completion thus it was concentrated under reduced pressure, the residue dissolved in MeOH and loaded on a SCX cartridge washing with MeOH and eluting with H₃ 2M in MeOH affording the title compound D40 (33 mg). UPLC (GEN_QC_SS): rt = 0.48 min, peak observed: 272 (M+l). Ci₃Hi₆F₃N₃ requires 271. Description 41 : 1,1-dimethylethyl (lR,4S,6R)-4-{(E/Z)-2-[6-methyl-4-(trifluoromethyl)- 3-pyridazinyl]ethenyl}-3-azabicyclo[4.1.0]heptane-3-carboxylate (D41)

To a degassed solution of 1, 1-dimethylethyl (lR,4S,6R)-4-[(E/Z)-2-(4,4,5,5-tetramethyl- l,3,2-dioxaborolan-2-yl)ethenyl]-3-azabicyclo[4.1.0]heptane-3-carboxylate D6 (90 mg) and 3-chloro-6-methyl-4-(trifluoromethyl)pyridazine (60.8 mg, 0.309 mmol) in DME (3 ml) and sodium carbonate 2N solution (1 ml, 0.258 mmol), bis(triphenylphosphine)palladium(II) chloride (18.09 mg, 0.026 mmol) was added and the mixture was heated to 90°C and stirred at that temperature for 1 hour. The mixture was cooled down to room temperature then partitioned between water and EtOAc. Organic phase was dried over Na₂S0₄, filtered and concentrated under reduced pressure. Crude was purified by flash chromatography on silica gel (Biotage SP1, SNAP 10 g, eluentCy to Cy/EtOAc 6:4) affording the title compound D41 (38 mg).

UPLC (GEN_QC_SS): rt = 1.00 min, peak observed: 384 (M+l). Ci₉H₂₄F₃N₃0₂ requires 383.

Description 42: 1,1-dimethylethyl (lR,4R,6R)-4-{2-[6-methyl-4-(trifluoromethyl)-3- pyridazinyl] ethyl}-3-azabic clo [4.1.0] heptane-3-carboxylate (D42)

To a solution of 1, 1-dimethylethyl (lR,4S,6R)-4-{(E/Z)-2-[6-methyl-4-(trifluoromethyl)-3- pyridazinyl]ethenyl}-3-azabicyclo[4.1.0]heptane-3-carboxylate D41 (38 mg) in MeOH (8 ml), Pd/C (10.55 mg, 9.91 μπιοΐ) was added and the reaction was hydrogenated at room temperature for 1 hour. Then the mixture was filtered over a pad of Celite washing with MeOH, solvent was eliminated under reduced pressure affording the title compound D42

(34 mg).

UPLC (GEN_QC_SS): rt = 1.00 min, peak observed: 386 (M+l). Ci₉H₂₆F₃N₃0₂ requires 385. Description 43: (lR,4R,6R)-4-{2-[6-methyl-4-(trifluoromethyl)-3-pyridazinyl]ethyl}-3- azabicyclo[4.1.0]heptane (D43)

To a solution of 1,1 -dimethyl ethyl (lR,4R,6R)-4-{2-[6-methyl-4-(trifluoromethyl)-3- pyridazinyl]ethyl}-3-azabicyclo[4.1.0]heptane-3-carboxylate D42 (34 mg) in dry DCM (2 ml),TFA (0.340 ml 4.41 mmol) was added and the mixture was stirred at room temperature for 45 minutes. Reaction was gone to completion thus it was concentrated under reduced pressure, the residue dissolved in MeOH and loaded on a SCX cartridge washing with MeOH and eluting with NH₃ 2M in MeOH affording the title compound D43 (26 mg). UPLC (GEN_QC_SS): rt = 0.48 min, peak observed: 286 (M+l). d₄Hi₈F₃N₃ requires 285.

Description 44: 1,1-dimethylethyl (lR,4S,6R)-4-{[6-methyl-4-(trifluoromethyl)-2- pyridinyl] ethynyl}-3-azabic clo [4.1.0] heptane-3-carboxylate (D44)

In a microwave vial 1,1-dimethylethyl (lR,4S,6R)-4-ethynyl-3-azabicyclo[4.1.0]heptane-3- carboxylate D5 (250 mg), 2-chloro-6-m ethyl -4-(trifluoromethyl)pyri dine (221 mg, 1.130 mmol), Cs₂C0₃ (368 mg, 1.130 mmol), bis(triphenylphosphine)palladium(II) chloride (15.86 mg, 0.023 mmol), tri-t-butylphosphine (10.96 μΐ, 0.045 mmol) and DBU (14 μΐ, 0.093 mmol) were dissolved in DMF (4 ml). The vial was sealed under nitrogen and the mixture was irradiated for 10 minutes at 150 °C.

The reaction mixture was cooled to 23 °C, diluted with EtOAc (30 ml) and filtered through a Celite pad. The filtrate was washed with brine (3 x 20 ml) and the combined aqueous layers were back extracted with EtOAc (2 x 5 ml). Organic layers were dried (Na₂S0₄), filtered and evaporated.

The brown oil obtained was purified by column chromatography (SNAP KP-Sil 50g; eluted with Cy/EtOAc 3CV from 100% Cy to 90/10, 5CV 90/10).

Evaporated fractions gave the title compound D44 as yellow oil (128 mg).

UPLC (IPQC): rt = 1.43 minutes, peak observed: 381 (M+l) C₂₀H₂₃F₃N₂O₂ requires: 380.

¹H NMR (400 MHz, CHLOROFORM-^ δ ppm 0.03 (br. s., 1 H) 0.75 (td, 1 H) 0.97 - 1.20 (m, 2 H) 1.42 - 1.54 (m, 9 H) 1.93 (br. s., 1 H) 2.27 (br. s., 1 H) 2.60 - 2.71 (m, 3 H) 3.74

(br. s., 1 H) 4.01 (d, 1 H) 4.94-5.32 (br. s., 1 H) 7.30 - 7.34 (m, 1 H) 7.47 (s, 1 H) Description 45: 1,1-dimethylethyl (lR,4R,6R)-4-{2-[6-methyl-4-(trifluoromethyl)-2- pyridinyl] ethyl}-3-azabic clo [4.1.0] heptane-3-carboxylate (D45)

1,1-dimethylethyl (lR,4S,6R)-4-{[6-methyl-4-(trifluoromethyl)-2-pyridinyl]ethynyl}-3- azabicyclo[4.1.0]heptane-3-carboxylate D44 (128 mg) was dissolved in MeOH (8 ml), Pd/C (35.8 mg, 0.034 mmol) was added and the resulting suspension was stirred under hydrogen atmosphere. After 2 hours the reaction mixture was filtered and the solvent evaporated to dryness.

It was obtained the title compound D45 (121 mg) as colorless oil.

UPLC (IPQC): rt = 1.4 minutes, peak observed: 385 (M+l) C20H27F3N2O2 requires: 384.

Description 46: (lR,4R,6R)-4-{2-[6-methyl-4-(trifluoromethyl)-2-pyridinyl]ethyl}-3- azabicyclo[4.1.0]heptane (D46)

To a solution of 1,1-dimethylethyl (lR,4R,6R)-4-{2-[6-methyl-4-(trifluoromethyl)-2- pyridinyl]ethyl}-3-azabicyclo[4.1.0]heptane-3-carboxylate D45 (126 mg) in dry DCM (4 ml), TFA (1.263 ml, 16.39 mmol) was added and the mixture was stirred at room temperature for 45 minutes. Reaction was gone to completion thus it was concentrated under reduced pressure, the residue dissolved in MeOH and loaded on a SCX cartridge washing with MeOH and eluting with H₃ 2M in MeOH affording the title compound D46 (91 mg).

UPLC (IPQC): rt = 0.67 min, peak observed: 285 (M+l). Ci₅Hi₉F₃N₂ requires 284.

1H MR (400 MHz, CHLOROFORM-^ δ ppm 0.17 (q, 1 H) 0.67 (td, 1 H) 1.01 - 1.13 (m, 2 H) 1.49 - 1.64 (m, 1 H) 1.68 - 1.85 (m, 3 H) 1.93 (dd, 1 H) 2.19 (m, 1 H) 2.57 - 2.65 (m, 3 H) 2.72 - 2.82 (m, 1 H) 2.82 - 2.99 (m, 2 H) 3.46 - 3.59 (m, 1 H) 7.13 - 7.24 (m, 2 H)

Description 47: 1,1-dimethylethyl (lR,4S,6R)-4-{(E/Z)-2-[5-(trifluoromethyl)-l,3,4- thiadiazol-2-yl] ethenyl}-3-azabicyclo [4.1.0] heptane-3-carboxylate (D47)

To a degassed solution of 1,1-dimethylethyl (lR,4S,6R)-4-[(E/Z)-2-(4,4,5,5-tetramethyl- l,3,2-dioxaborolan-2-yl)ethenyl]-3-azabicyclo[4.1.0]heptane-3-carboxylate D6 (80 mg), 2- chloro-5-(trifluoromethyl)-l,3,4-thiadiazole (51.8 mg, 0.275 mmol) in DME (1.5 ml) and sodium carbonate 2M solution (0.115 ml, 0.229 mmol)

bis(triphenylphosphine)palladium(II) chloride (16.08 mg, 0.023 mmol) was added and the mixture was heated to 90°C and stirred at that temperature for 1 hour. Reaction was gone to completion, thus the mixture was cooled down to room temperature and diluted with EtOAc. Organic phase was washed with water, dried overNa₂S0₄, filtered and concentrated under reduced pressure. Crude was purified by flash chromatography on silica gel (Biotage SP 1 , SNAP 10 g, eluent: Cy to Cy/EtOAc 8 :2) affording the title compound D47 (46 mg). UPLC (IPQC): rt = 1.30 min, peak observed: 376 (M+l). Ci₆H₂oF₃N30₂S requires 375.

Description 48: 1,1-dimethylethyl (lR,4R,6R)-4-{2-[5-(trifluoromethyl)-l,3,4- thiadiazol-2-yl] ethyl}-3-azabicyclo [4.1.0] heptane-3-carboxylate (D48)

To a solution of 1,1-dimethylethyl (lR,4S,6R)-4-{(E/Z)-2-[5-(trifluoromethyl)-l,3,4- thiadiazol-2-yl]ethenyl}-3-azabicyclo[4.1.0]heptane-3-carboxylate D47 (46 mg) in MeOH (8 ml), Pd/C (13.04 mg, 0.012 mmol) was added and the reaction was hydrogenated at atmospheric pressure and at room temperature for 1 hour. Then the mixture was filtered over a pad of Celite washing with MeOH, solvent was eliminated under reduced pressure affording the title compound D48 (38 mg).

UPLC (IPQC): rt = 1.30 min, peak observed: 378 (M+l). Ci₆H₂₂F₃N₃0₂S requires 377. 1H NMR (400 MHz, CHLOROFORM-^ δ ppm -0.07 - 0.14 (m, 1 H) 0.62 - 0.82 (m, 1 H) 0.86 - 1.08 (m, 2 H) 1.34 - 1.56 (m, 9 H) 1.70 - 1.93 (m, 2 H) 2.03 (br. s., 1 H) 2.24 - 2.46 (m, 1 H) 3.06 - 3.22 (m, 2 H) 3.22 - 3.40 (m, 1 H) 4.00 (br. s., 1 H) 4.14 (br. s., 1 H)

Description 49: (lR,4R,6R)-4-{2-[5-(trifluoromethyl)-l,3,4-thiadiazol-2-yl]ethyl}-3- azabicyclo[4.1.0]heptane (D49)

To a solution of 1,1-dimethylethyl (lR,4R,6R)-4-{2-[5-(trifluoromethyl)-l,3,4-thiadiazol-2- yl]ethyl}-3-azabicyclo[4.1.0]heptane-3-carboxylate D48 (38 mg) in dry DCM (2 ml), TFA (0.388 ml, 5.03 mmol) was added and the mixture was stirred at room temperature for 45 minutes. Reaction was gone to completion thus it was concentrated under reduced pressure, the residue dissolved in MeOH and loaded on a SCX cartridge washing with MeOH and eluting with ¼ 2M in MeOH affording the title compound D49 (27 mg).

UPLC (IPQC ): rt = 0.56 min, peak observed: 278 (M+l). C₁₁H₁₄F₃N₃S requires 277. Description 50: 3-(trifluoromethyl)pyrazine 1-oxide (D50)

CF₃

O

A mixture of 2-(trifluoromethyl)pyrazine (2 g, 13.51 mmol), acetic acid (3.8 ml, 66.4 mmol) and hydrogen peroxide 30% (2.5 ml, 24.47 mmol) was stirred 70°C for 72 hours. The reaction mixture was cooled down to room temperature and the volatiles were evaporated under vacuum. The obtained slurry was treated with DCM/water 50ml/30ml.

The phases were separated and the aqueous one was back extracted with DCM (2x50ml). Combined organics were washed with saturated solution of NaHC0₃ (20ml), brine (20ml), dried over Na₂S0₄ and evaporated to dryness to get the title compound D50 (1.16 g,) as waxy solid. It was used without further purification in next steps.

1H MR (400 MHz, DMSO-i¾) δ ppm 8.61 (dd, 1 H) 8.72 (d, 1 H) 8.98 (s, 1 H)

Description 51: 2-chloro-6-(trifluoromethyl)pyrazine (D51)

3-(trifluoromethyl)pyrazine 1-oxide D50 (100 mg) was dissolved in POCl₃ (1 ml, 10.73 mmol) and heated at 100 °C for 2 hours. The reaction was poured in ice and diluted with 20 ml of NaHC0₃ saturated solution. The product was extracted with Et₂0 (3 x 5 ml). The combined organic layers were evaporated in a distillation apparatus in order to remove the ethereal solvent, affording the title compound D51 (90 mg).

1H MR (500 MHz, DMSO-i¾) δ ppm 9.19 (s, 1 H) 9.23 (s, 1 H)

Description 52: 1,1-dimethylethyl (lR,4S,6R)-4-{(E/Z)-2-[6-(trifluoromethyl)-2- pyrazinyl] ethenyl}-3-azabic clo [4.1.0] heptane-3-carboxylate (D52)

To a degassed solution of 1,1-dimethylethyl (lR,4S,6R)-4-[(E/Z)-2-(4,4,5,5-tetramethyl- l,3,2-dioxaborolan-2-yl)ethenyl]-3-azabicyclo[4.1.0]heptane-3-carboxylate D6 (32 ml) and 2-chloro-6-(trifluoromethyl)pyrazine D51 (25 mg) in DME (3 ml) and sodium carbonate 2M (1 ml, 0.092 mmol), bis(triphenylphosphine)palladium(II) chloride (6.43 mg, 9.16 μπιοΐ) was added and the mixture was heated to 90°C and stirred at that temperature for lhour. The mixture was cooled down to room temperature, then partitioned between water and EtOAc. Organic phase was dried over Na₂S0₄, filtered and concentrated under reduced pressure. Crude was purified by flash chromatography on silica gel (SNAP 10 g, eluen Cy to Cy/EtOAc 8:2) affording the title compound D52 (12.6 mg).

UPLC (Acid GEN_QC_SS): rt = 1.05 minutes, peak observed: 370 (M+l) 270 (M+l-Boc) C18H22F3N3O2 requires: 369.

Description 53: 1,1-dimethylethyl (lR,4R,6R)-4-{2-[6-(trifluoromethyl)-2- pyrazinyl] ethyl}-3-azabic clo [4.1.0] heptane-3-carboxylate (D53)

To a solution of 1,1-dimethylethyl (lR,4S,6R)-4-{(E/Z)-2-[6-(trifluoromethyl)-2- pyrazinyl]ethenyl}-3-azabicyclo[4.1.0]heptane-3-carboxylate D52 (39 mg) in MeOH (8 ml), Pd/C (11.24 mg, 10.56 μιηοΐ) was added and the reaction was stirred under hydrogen atmosphere at room temperature for 1 hour. Then the mixture was filtered over a pad of Celite washing with MeOH, solvent was eliminated under reduced pressure and the residue was purified by flash chromatography on silica gel (SNAPIO g, eluentCy to Cy/EtOAc 8:2) to afford the title compound D53 (26 mg).

UPLC (GEN_QC_SS): rt = 1.06 minutes, peak observed: 372 (M+l) 272 (M+l-Boc) Ci₈H₂4F₃N₃0₂ requires: 371.

Description 54: (lR,4R,6R)-4-{2-[6-(trifluoromethyl)-2-pyrazinyl]ethyl}-3- azabicyclo[4.1.0]heptane (D54)

To a solution of 1,1-dimethylethyl (lR,4R,6R)-4-{2-[6-(trifluoromethyl)-2- pyrazinyl]ethyl}-3-azabicyclo[4.1.0]heptane-3-carboxylate D53 (26 mg) in dry DCM (2 ml),TFA (0.270 ml, 3.50 mmol) was added and the mixture was stirred at room temperature for 45 minutes. Reaction was gone to completion thus it was concentrated under reduced pressure, the residue dissolved in MeOH and loaded on a SCX cartridge washing with MeOH and eluting with NH₃ 2M in MeOH affording the title compound D54 (18.6 mg). UPLC (GEN_QC_SS): rt = 0.50 minutes, peak observed: 272 (M+l) Ci₃Hi₆F₃N₃ requires: 271.

1H NMR (400 MHz, CHLOROFORM-^ δ ppm 0.13 - 0.26 (m, 1 H) 0.71 (td, 1 H) 1.01 - 1.17 (m, 2 H) 1.53 - 1.71 (m, 1 H) 1.83 - 2.06 (m, 3 H) 2.22 - 2.36 (m, 1 H) 2.74 - 2.87 (m, 1 H) 2.94 - 3.14 (m, 2 H) 3.56 (dd, 1 H) 8.66 - 8.74 (m, 1 H) 8.79 (s, 1 H)

Description 55: 2,3-dimethylpyrazine 1-oxide (D55)

2,3-dimethylpyrazine (5 g, 46.2 mmol) was dissolved in Acetic Acid (15.41 ml) and H₂0₂ (9.45 ml, 92 mmol) was added and left under stirring at 35°C for 4 days, then left at room temperature over weekend, then 0.2 equivalents of H₂0₂ were added and the mixture stirred at 35°C for further 2 days. The reaction mixture was slowly and carefully poured in a flask containing a saturated K₂C0₃ aqueous solution then it was extracted with EtOAc (5x50 ml), the organic phase was dried (Na₂S0₄) and evaporated under reduced pressure to give the title compound D55 (4.13 g) as white solid.

UPLC (IPQC): rt = 0.32 minutes peak observed: 125 (M+l) C₆H₈N₂0 requires 124.

1H MR (400 MHz, DMSO-i¾) δ ppm 2.32 - 2.40 (m, 3 H) 2.51 (s, 3 H) 8.17 - 8.29 (m, 2

H)

Description 56: 5-chloro-2,3-dimethylpyrazine (D56)

In a 250 ml round-bottomed flask 2,3-dimethylpyrazine 1 -oxide D55 (4.13 g) and POCl₃ (31.0 ml, 333 mmol) were added and stirred at reflux for 3 hours. After this time the reaction mixture was cooled to room temperature and added into a 11 flask containing ice. The pH value of the medium was adjusted to 8 by the addition of solid KOH and then the mixture was extracted with EtOAc (5x200 ml). The organic phase was dried (Na₂S0₄) and evaporated under reduced pressure to give a dark brown oil. This material was purified by column chromatography on silica gel (SNAP 100 g, Cy/EtOAc = from 9: 1 to 7:3) to afford the title compound D56 (722 mg) as yellow oil.

UPLC (IPQC): rt = 0.70 minutes peak observed: 143 (M+l) C₆H₇C1N₂ requires 142.

1H NMR (400 MHz, CHLOROFORM-^ δ ppm 2.54 (s, 6 H) 8.32 (s, 1 H).

Description 57: 1,1-dimethylethyl (lR,4S,6R)-4-[(E/Z)-2-(5,6-dimethyl-2- pyrazinyl)ethenyl]-3-azabic clo [4.1.0] heptane-3-carboxylate (D57)

To a degassed solution of 1,1-dimethylethyl (lR,4S,6R)-4-[(E/Z)-2-(4,4,5,5-tetramethyl- l,3,2-dioxaborolan-2-yl)ethenyl]-3-azabicyclo[4.1.0]heptane-3-carboxylate D6 (150 mg) and 5-chloro-2,3-dimethylpyrazine D56 (73.5 mg) in 1,2- DME (3 ml) sodium carbonate 2M (1 ml, 2.000 mmol), dichloropalladium - triphenylphosphane (1 :2) (30.1 mg, 0.043 mmol) was added and the mixture was heated to 90°C for 1.5 hours. The mixture was cooled down to room temperature, then diluted with EtOAc and washed with water and brine. Organic phase was dried over Na₂S0₄, filtered and concentrated under reduced pressure. Crude was purified by flash chromatography on silica gel (Cy to Cy/

EtOAc 1 : 1) affording the title compound D57 (26.6 mg).

UPLC (IPQC): rt = 1.18 minutes peak observed: 330 (M+l) Ci₉H₂7N₃0₂ requires 329.

Description 58: 1,1-dimethylethyl (lR,4R,6R)-4-[2-(5,6-dimethyl-2-pyrazinyl)ethyl]-3- azabicyclo [4.1.0] heptane-3-carboxylate (D58)

To a solution of 1,1-dimethylethyl (lR,4S,6R)-4-[(E/Z)-2-(5,6-dimethyl-2- pyrazinyl)ethenyl]-3-azabicyclo[4.1.0]heptane-3-carboxylate D57 (49 mg) in MeOH (8 ml), Pd/C (15.83 mg, 0.015 mmol) was added and the reaction was hydrogenated at atmospheric pressure at room temperature for 30 minutes. Then the mixture was filtered over a pad of Celite washing with MeOH, solvent was eliminated under reduced pressure affording the title compound D58 (49 mg)

UPLC (IPQC): rt = 1.15 minutes peak observed: 332 (M+l) Ci₉H₂₉N₃0₂ requires 331.

Description 59: (lR,4R,6R)-4-[2-(5,6-dimethyl-2-pyrazinyl)ethyl]-3- azabicyclo[4.1.0]heptanes (D59)

To a solution of 1,1-dimethylethyl (lR,4R,6R)-4-[2-(5,6-dimethyl-2-pyrazinyl)ethyl]-3- azabicyclo[4.1.0]heptane-3-carboxylate D58 (49 mg) in dry DCM (2 ml),TFA (0.285 ml, 3.70 mmol) was added and the mixture was stirred at room temperature for 45 minutes. Reaction was gone to completion thus it was concentrated under reduced pressure, the residue dissolved in MeOH and loaded on a SCX cartridge washing with MeOH and eluting with H₃ 2M in MeOH affording the title compound D59 (29.6 mg).

UPLC (IPQC): rt = 0.46 minutes, peak observed: 232 (M+l) Ci₄H₂iN₃ requires: 231.

Description 60: 2-methylfuro [3,4-b]pyridine-5,7-dione (D60) In a 100 ml round-bottomed flask 6-methyl-2,3-pyridinedicarboxylic acid (10 g, 55.2 mmol) and acetic anhydride (26 ml, 276 mmol) were added and heated at 100 °C under nitrogen for 5 hours. After this time the volatiles were removed under vacuum to give the title compound D60 (8.2 g) as a slightly brown solid. 1H NMR (400 MHz, DMSO-i¾) δ ppm 8.41 (d, 1 H), 7.82 (d, 1 H), 2.73 (s, 3 H).

Description 61: 6-methyl-2-[(methyloxy)carbonyl]-3-pyridinecarboxylic acid (D61)

2-methylfuro[3,4-b]pyridine-5,7-dione D60 (3 g) was added portionwise over 5 minutes to stirred MeOH (20 ml) at 0 °C. The mixture was stirred at 0 °C for 30 minutes then at room temperature for other 2.5 hours. The solution was evaporated at reduced pressure and the residue recrystallized from toluene (50 ml). The solid was filtered and dried under high vacuum for 30 minutes, obtaining a first batch of the title compound D61 (1.16 g) as pale brown solid. From the toluene solution new solid precipitated: this solid was filtered and dried under high vacuum for 30 minutes, obtaining a second batch of the title compound D61 (352 mg) as pale yellow solid. The toluene solution was then evaporated at reduced pressure and the residue recrystallized again from toluene (25 ml). The solid was filtered and dried under high vacuum for 30 minutes, obtaining a third batch of the title compound D61 (615 mg) as pale yellow solid. UPLC (Basic GEN QC): rt = 0.23 minutes, peak observed: 195 (M+1). C₉H₉N0₄ requires 196. 1H MR (400 MHz, DMSO-i¾) δ ppm 13.61 (br. s., 1 H), 8.09 - 8.31 (m, 1 H), 7.51 (m, 1 H), 3.82 (s, 3 H), 2.55 (s, 3 H).

Description 62: methyl 3-({[(l,l-dimethylethyl)oxy]carbonyl}amino)-6-methyl-2- pyridinecarboxylate (D62)

6-methyl-2-[(methyloxy)carbonyl]-3-pyridinecarboxylic acid D61 (1.15 g) was suspended toluene (40 ml) and DIPEA (1.25 ml, 7.16 mmol) was added, causing the complete dissolution of the solid. This mixture was stirred 10 minutes at room temperature, then diphenyl azidophosphate (1.35 ml, 6.26 mmol) was added in one portion and the mixture was stirred at reflux for 1 hour. The solution was cooled at room temperature and t-BuOH (2.5 ml, 26 mmol) was added in one portion. The mixture was then stirred at 70 °C for 1 hour and then cooled at room temperature, Et₂0 (50 ml) was added and the resulting solution washed with NaHC0₃ saturated solution (3 x 60 mis). The water phases were joined together and back-extracted with Et₂0 (50 ml). The two organic solutions were joined together, dried over Na₂S04 and evaporated at reduced pressure, obtaining the crude target material as pale yellow oil. This material was purified by flash chromatography on silica gel (Biotage, EtOAc/Cy from 10/90 to 70/30; Snap- 100 g column). The title compound D62 (1.315 g) was obtained as white solid. UPLC (Basic GEN QC): rt = 0.68 minutes, peak observed: 267 (M+1). C13H18N2O4 requires 266. 1H NMR (400 MHz, CDC1₃) δ ppm 10.13 (bs., 1 H), 8.77 (d, 1 H), 7.34 (d, 1 H), 4.03 (s, 3 H), 2.59 (s, 3 H), 1.53 - 1.56 (m, 9 H).

Description 63: methyl 3-amino-6-methyl-2-pyridinecarboxylate (D63)

Methyl 3 -({ [(1 , 1 -dimethyl ethyl)oxy]carbonyl } amino)-6-methyl-2-pyridinecarboxylate D62 (1.3 g) was dissolved in DCM (80 ml) and the mixture stirred at 0 °C. A solution of TFA (5 ml, 64.9 mmol) in DCM (10 ml) was dropped into the cold mixture over 3 minutes. The resulting solution was left under stirring at 0 °C for 30 minutes, then the mixture was left still at room temperature overnight. TFA (4 ml, 51.9 mmol) dissolved in DCM (10 ml) was added over 3 minutes and the mixture stirred again at room temperature for 5 hours. The solution was loaded onto an SCX-25 g column and the column was eluted firstly with DCM (100 ml) and then MeOH (20 mis). The material was collected eluting with NH₃ (2M in MeOH, 100 mis) and after evaporation under reduced pressure of the ammonia solution it was obtained the title compound D63 (770 mg) was obtained as a white solid. UPLC (Basic GEN QC): rt = 0.44 minutes, peak observed: 167 (M+1). C₈Hi₀N₂O₂ requires 166. 1H NMR (400 MHz, CDC1₃) δ ppm 7.14 (d, 1 H), 7.01 (d, 1 H), 3.99 (s, 3 H), 2.52 (s, 3 H).

Description 64: methyl 3-iodo-6-methyl-2-pyridinecarboxylate (D64)

HC1 6 M solution in water (4.5 ml, 27.0 mmol) was added to methyl 3-amino-6-methyl-2- pyridinecarboxylate D63 (768 mg) and the resulting pale yellow mixture was sequentially diluted with water (4 x 5 ml) and chilled at 0 °C (internal temperature).

A solution of sodium nitrite (480 mg, 6.96 mmol) in water (2 ml) was dropped into the mixture over 1 minute. After this addition the mixture was stirred at 0 °C for 30 minutes, then a solution of KI (1.69 g, 10.18 mmol) in water (2 ml) was added over 1 minute, causing the formation of a dark violet crust (moderate gas evolution). The mixture was left under stirring for 1 hour: during this period the temperature passed from 0 °C to + 5 °C. EtOAc (50 ml) was then added to the stirred mixture, causing the dissolution of the dark solid. Water (50 ml) and EtOAc (50 ml) were added and the whole mixture was poured into a separator funnel. After the separation of the two phases, the water phase was extracted with EtOAc. All the organic phases were joined together and washed with NaHC0₃ saturated solution; the acidic water phase was neutralized by the addition of the previously used NaHC0₃ saturated solution and the resulting mixture extracted with EtOAc (2 x 50 ml). All the organic phases were joined together, dried over Na₂S0₄ and evaporated at reduced pressure, obtaining the crude target material as dark brown/violet oil. This material was purified by silica gel chromatography (Biotage SP4 Snap-100 g column, EtOAc /Cy from 10/90 to 30/70). The title compound D64 was obtained as a pale brown solid (1.1 g). UPLC (Basic GEN QC): rt = 0.68 minutes, peak observed: 278 (M+l). C₈H₈IN0₂ requires 277. 1H MR (400 MHz, CDC1₃) δ ppm 8.12 (d, 1 H), 7.01 (d, 1 H), 4.01 (s, 3 H), 2.58 (s, 3 H).

Description 65: methyl 6-methyl-3-(2-pyrimidinyl)-2-pyridinecarboxylate (D65)

To a suspension of methyl 3-iodo-6-methyl-2-pyridinecarboxylate D64 (300 mg), CsF (329 mg, 2.166 mmol) and Pd(Ph₃P)₄ (50.0 mg, 0.043 mmol) in DMF (10 ml) stirred under nitrogen at room temperature was added 2-(tributylstannanyl)pyrimidine (480 mg, 1.299 mmol). The reaction mixture was stirred at 130 °C for 30 minutes at microwave Personal Chemistry. The reaction mixture was partitioned between EtOAc and aqueous NaHC0₃ saturated solution the combined organic phases were dried to give the crude product which was purified by silica gel chromatography (SNAP KP-NH 55 g; Cy/EtOAc 15 column volumes from 100/0 to 70/30). Collected fractions were evaporated to obtain the title compound D65 (101 mg) as white solid. UPLC (Basic GEN QC): rt = 0.56 minutes, peak observed: 230 (M+l). Ci₂HnN₃0₂ requires 229. 1H NMR (400 MHz, DMSO-i¾) δ ppm 8.92 (d, 2 H), 8.49 (d, 1 H), 7.44 - 7.63 (m, 2 H), 3.75 (s, 3 H), 2.57 (s, 3 H).

Description 66: 6-methyl-3-(2-pyrimidinyl)-2-pyridinecarboxylic acid lithium salt (D66)

Li

To a solution of methyl 6-methyl-3-(2-pyrimidinyl)-2-pyridinecarboxylate D65 (100 mg) in MeOH (4.5 ml) and water (1.1 ml) was added Li OH (13.58 mg, 0.567 mmol) and the resulting mixture was submitted to microwave irradiation at 60 °C for 85 minutes. After this time the solvents were removed under reduced pressure to give the title compound D66 (100 mg) as a white solid. CnH₈N₃0₂-Li⁺ requires 221. 1H MR (400 MHz, DMSO- ,) δ ppm 8.78 (m, 2 H), 7.86 (m, 1 H), 7.37 (m, 1 H), 7.24 (m, 1 H), 2.50 (s, 3 H).

Description 67: 3-(5,5-Dimethyl-l,3,2-dioxaborinan-2-yl)-6-methyl-2- pyridinecarbonitrile (D67)

2,2,6,6-tetramethylpiperidine (3.49 ml, 20.52 mmol) was dissolved in dry THF (25ml) under argon and stirred at -30 °C; BuLi (13.33 ml, 21.33 mmol) 1.6 M in hexane was added over 5 min (the temperature never exceeded -25 °C). The yellow solution was stirred at -30 °C for 20 min, then chilled at -78 °C and tris(l -methylethyl) borate (4.38 ml, 18.96 mmol) was added over 5 min (the temperature never exceeded -73 °C).

After 10 min at -78 °C, 6-methyl-2 -pyridinecarbonitrile (2.0 g, 16.93 mmol) dissolved in dry THF (14 ml) was added dropwise (over 20 min) maintaining internal temperature below -73 °C and the mixture became dark-brown. The mixture was stirred at -73 °C for 2 hours. The mixture was quenched with AcOH (2.374 ml, 41.5 mmol) dropwise at -73 °C (the temperature never exceeded -60 °C and the mixture became brilliant orange). The cooling bath was removed and the mixture left to reach the room temperature: during this period the mixture became thick and new THF (8 ml) had to be added in order to have a better stirring. The mixture was stirred 10 min at room temperature then 2,2-dimethyl- 1,3 -propanediol (2.409 g, 23.13 mmol) was added in one portion and the mixture stirred at room temperature overnight. The solvent was evaporated and the orange residue taken-up with DCM (100 ml) and 10 % water solution of KH₂PO₄ (100 ml). The phases were separated and the water phase was back-extracted with DCM (50 ml). The combined organic phases were washed with 10 % water solution of KH₂PO₄ (50 ml). The DCM was evaporated. The residue was dissolved in Et₂0 (100 ml) and extracted with NaOH 0.05 M (5 x 50 ml, boronic ester in water phase). The aqueous phases were joined together and the pH was adjusted between pH = 4 and pH = 5 with 10 % water solution of KH₂P0₄ (50 ml). The so obtained yellow solution was extracted with EtOAc (3 x 200 ml). All the organics joined together were dried (Na₂S0₄) and evaporated the title compound D67 (2.29 g) of as yellow oil, that solidified on standing. C₁₂H₁₅BN₂O₂ requires 230. 1H MR (400 MHz, CDC1₃) δ ppm 7.97 - 8.15 (m, 1 H), 7.31 - 7.36 (m, 1 H), 3.85 (m, 4 H), 2.52 - 2.73 (s, 3 H), 0.97 - 1.10 (m, 6 H).

Description 68: 6-Methyl-3-(2-pyrimidinyl)-2-pyridinecarbonitrile (D68)

A) Isopropylmagnesium chloride-LiCl (37.9 ml, 36.5 mmol) was added portion wise (in overall 10 min) to a solution of 3-bromo-6-methyl-2-pyridinecarbonitrile (4 g, 20.30 mmol in THF (150 ml) cooled to -70 °C (internal temperature). The reaction was kept to that temperature for 15 min. Then it was allowed to gently warm up to -40 °C in overall 1 hour. Then, it was cooled to -78 °C and zinc chloride (3.32 g, 24.36 mmol) was added. The resulting mixture was allowed to warm up to room temperature in 1 hour. Pd(Ph₃P)₄ (2.346 g, 2.030 mmol), 2-chloropyrimidine (3 g, 26.2 mmol) were added and the mixture was refluxed (external temperature 100 °C) until complete consumption of starting

chloropyrimidine (3 hours). The reaction mixture was cooled to room temperature and poured into water (200 ml) cooled to 10 °C. It was then extracted with EtOAc (5 x 200mls). The collected organic phases, containing large amount of colloid material and water, were washed with brine (200 ml). The water phase was filtered over a gouch, and the solid material was washed with further EtOAc (2 x 300mls). The collected organic phases were dried overnight over Na₂S0₄, filtered and concentrated to give (7 g) the crude material which was purified (Biotage Spl over a 240 g Silica Anolgix column, with a 25 g pre- column) to give the title compound D68 as yellow solid (1.8 g). UPLC (Acid

GEN_QC_SS): rt = 0.58 minutes, peak observed: 197 (M+l). Cn¾N₄ requires 196.

B) An alternative method to make D68 is: 3-(5,5-dimethyl-l,3,2-dioxaborinan-2-yl)-6- methyl-2-pyridinecarbonitrile D67 (50.6 mg) was dissolved 1,4-Dioxane (1 ml) under nitrogen in a vial, then 2-bromopyrimidine (42.0 mg, 0.264 mmol), CsF (67 mg, 0.441 mmol), Pd(Ph₃P)₄ (12 mg, 10.38 μιηοΐ) and Cul (7 mg, 0.037 mmol) were added in sequence. The vial was then capped and stirred at 65 °C, after 1 hour the solvent was removed at reduced pressure and the residue partitioned between EtOAc (10 ml) and NaHC0₃ (saturated solution, 10 ml). The phases were separated and the water was extracted with EtOAc (2 x 10ml). The organic fraction were joined together, dried over Na₂S0 and evaporated at reduced pressure, obtaining an orange oily residue which was purified (Biotage, Snap 25 g silica gel column, EtOAc/Cy from pure Cy to 50:50 in 10 column volumes) to obtain the title compound D68 as pale yellow solid (27.6 mg).

Description 69: 6-Methyl-3-(2-pyrimidinyl)-2-pyridinecarboxylic acid (D69)

A) 6-methyl-3-(2-pyrimidinyl)-2-pyridinecarbonitrile D68 (0.8 g) was reacted in 6 M aqueous HC1 (40 ml, 240 mmol) at 80 °C for 3 hours, then solvent was removed under vacuum, and the resulting crude was purified (70 g Varian CI 8 column conditioning with MeOH (120 mis), then water (120 mis), loading in water, washing with water (200mls), product eluted with 100 % MeOH) to give the title compound D69 (0.6 g) as yellow solid. UPLC (Acid GEN_QC_SS): rt = 0.30 minutes, peak observed: 216 (M+l). CnH₉N₃0₂ requires 217. 1H MR (400 MHz, DMSO-i¾) δ ppm 13.07 (bs, 1 H), 8.78 - 9.01 (m, 2 H), 8.39 (m, 1 H), 7.39 - 7.67 (m, 2 H), 2.56 - 2.67 (s, 3 H). B) An alternative method to make D69 is as follows: 6-methyl-3-(2-pyrimidinyl)-2- pyridinecarbonitrile D68 (0.481 g) was suspended in EtOH (5 ml) and a solution of NaOH (0.490 g, 12.26 mmol) in water (5 ml) was added. The yellow mixture was stirred at 100 °C overnight. The yellow solution was cooled to 25 °C and HCl 6 M (1.0 ml) was added dropwise till pH = 4.5. The solvent was removed to give a yellow powder that was dried at 50 °C/vacuum for 1.5 hours to give the title compound D69 (1.242 g).

Description 70: methyl 6-methyl-3-(2H-l,2,3-triazol-2-yl)-2-pyridinecarboxylate (D70)

DMF (1.5 ml) was added to a mixture of methyl 3-iodo-6-methyl-2-pyridinecarboxylate D64 (100 mg), lH-l,2,3-triazole (49.9 mg, 0.722 mmol), (lR,2R)-N,N'-dimethyl-l,2- cyclohexanediamine (10.27 mg, 0.072 mmol), Cul (3.44 mg, 0.018 mmol) and Cs₂C0₃ (235 mg, 0.722 mmol) in a microwave vial. The mixture was degassed via three vacuum/nitrogen cycles then irradiated in a single mode microwave reactor to 120 °C for 20 minutes. The mixture was irradiated in a single mode microwave reactor to 120 °C for a further 40 minutes. The reaction mixture was cooled and filtered washing the solids with EtOAc (20 ml). The solids were dissolved in ph=3 buffer solution (5ml); UPLC check of this aqueous solution showed that it contained a considerable quantity of 6-methyl-3-(2H-l,2,3-triazol-2- yl)-2-pyridinecarboxylic acid. The aqueous phase was extracted repeatedly with DCM; the combined DCM extracts were diluted with MeOH (50ml) and treated with TMS- diazomethane. The volatiles were evaporated to give a yellow residue that was purified by flash chromatography on silica gel (Biotage, SNAP lOg column, 10%-50% EtOAc/Cy) to give the title compound D70 (38 mg) as a white solid. UPLC (Basic QC POS 50-800): rt = 0.57 minutes, peak observed: 219 (M+l). Ci₀Hi₀N₄O₂ requires 218. 1H NMR (400 MHz, CDC1₃) δ ppm 8.20 (d, 1 H), 7.87 (s, 2 H), 7.44 (d, 1 H), 3.94 (s, 3 H), 2.71 (s, 3 H).

Description 71: 6-methyl-3-(2H-l,2,3-triazol-2-yl)-2-pyridinecarboxylic acid (D71)

A solution of methyl 6-methyl-3-(2H-l,2,3-triazol-2-yl)-2-pyridinecarboxylate D70 (36 mg) and LiOH (5.93 mg, 0.247 mmol) in THF/water (2: 1, 3 ml) was stirred overnight. The mixture was evaporated under reduced pressure; the residue was taken up in water (2 ml) and neutralised with 1 M HCl water solution and then loaded onto a pre-conditioned C18 5 g column (the column was eluted with water and then MeOH). The methanol fractions were evaporated under reduced pressure to give the title compound D71 (34 mg) as a white solid. UPLC (Basic QC_POS_50-800): rt = 0.30 minutes peak observed: 205 (M+l). C₉¾N₄0₂ requires 204. 1H MR (400 MHz, MeOD) δ (ppm) 8.24 (d, 1 H), 7.99 (s, 2 H), 7.61 (d, 1 H), 2.67 (s, 3 H). '-dimethyl-2,3'-bipyridine-2'-carbonitrile (D72)

Pd(Ph₃P)₄ (37.7 mg, 0.033 mmol) was added to a mixture of 2-bromo-6-methylpyridine (157 mg, 0.913 mmol), 3-(5,5-dimethyl-l,3,2-dioxaborinan-2-yl)-6-methyl-2- pyridinecarbonitrile D67 (150 mg), copper(I) iodide (22.35 mg, 0.117 mmol) and cesium fluoride (198 mg, 1.304 mmol) in 1,4-dioxane (3 ml) at room temperature. The mixture was degassed via 3 vacuum/nitrogen cycles and sonicated briefly to homogenise the reaction mixture which was then heated to 65 °C with shaking for 2 hours. The mixture was cooled and filtered washing with EtOAc. The organic phase was evaporated under reduced pressure. This residue was purified by flash chromatography on silica gel (Biotage Snap 25 g column, EtOAc/Cy from 30/70 to 50/50) to give the title compound D72 (62 mg) as a pale yellow solid.

UPLC (Acid QC_POS _50-800): rt = 0.60 minutes, peak observed: 210 (M+l). Ci₃HnN₃ requires 209. 1H MR (400 MHz, CDCl₃) δ ppm 2.69 (s, 3 H) 2.69 (s, 3 H) 7.27 (d, 1 H) 7.49 (d, 1 H) 7.69 (d, 1 H) 7.77 (t, 1 H) 8.14 (d, 1 H). Description D73: 6-methyl-3-(2-methyl-4-pyrimidinyl)-2-pyridinecarboxylic acid

NaOH (46.6 mg, 1.166 mmol) in water (1 ml) was added to a suspension of 6,6'-dimethyl- 2,3'-bipyridine-2'-carbonitrile D72 (61 mg) in EtOH (1.5 ml) and the resulting mixture was heated to 100 °C with shaking for 6 hours. The mixture was evaporated under reduced pressure, the residue was taken up in water (2 ml) and acidified to pH = 2 with 2M HC1 solution. This mixture was loaded onto a pre-conditioned CI 8 cartridge (10 g, eluted with water and then MeOH). The MeOH fractions were evaporated under reduced pressure to give the title compound D73 (66 mg) as a pale yellow solid.

UPLC (Acid QC POS 50-800): rt = 0.33 minutes, peak observed: 185 [(M-C0₂)+1]. Ci₃Hi₂N₂0₂ requires 228. 1H MR (400 MHz, CDCh) δ ppm 2.65 (s, 3 H) 2.71 (s, 3 H) 7.24 (d, 1 H) 7.34 (d, 1 H) 7.50 (d, 1 H) 7.71 (t, 1 H) 7.89 (d, 1 H).

EXAMPLES Example 1: (lR,4R,6R)-3-{[6-methyl-3-(2-pyrimidinyl)-2-pyridinyl]carbonyl}-4-{2-[5- (trifluoromethyl)-2-pyridinyl]ethyl}-3-azabicyclo[4.1.0]heptane (El)

To a solution of (lR,4R,6R)-4-{2-[5-(trifluoromethyl)-2-pyridinyl]ethyl}-3- azabicyclo[4.1.0]heptane D23 (13 mg) in DCM (0.7 ml) were added 6-methyl-3-(2- pyrimidinyl)-2-pyridinecarboxylic acid D69 (34.5 mg) and DIPEA (0.025 ml, 0.144 mmol). To the yellowish suspension TBTU (17.91 mg, 0.056 mmol) was added and the reaction mixture was stirred at 23 °C for 1 hour. Saturated NaHC0₃ (2 ml) and DCM (2 ml) were added to the reaction mixture and the biphasic system was separated through a phase separator cartridge. The aqueous layer was back extracted with DCM (3 x 2 ml). The combined organic layers were washed with water (3 x 5 ml), dried over Na₂S0₄, filtered and evaporated under reduced pressure. The brown oil obtained was charged on a SCX (500 mg), washed with MeOH (18 ml) and eluted with 2M H₃/MeOH (5 ml). The ammoniac fraction was evaporated to give a yellow oil containing desired compound. It was further purified by silica gel chromatography (SNAP KP-NH 10 g; eluted with Cy/EtOAc 4C V from 100% Cy to 50/50, 4CV 50/50, 4CV from 50/50 to 100% EtOAc).

Evaporated fractions gave the title compound El as white solid (6.5 mg).

UPLC (IPQC) rtl = 1.05 minutes, rt2 = 1.14 minutes (rotamers present) peaks observed: 468 (M+l) C25H₂4F₃N₅0 requires 467.

1H NMR (500 MHz, DMSO-i¾) δ ppm 0.51 - 0.63 (m, 2 H) 0.82 - 0.93 (m, 1 H) 0.94 - 1.04 (m, 1 H) 1.71 - 1.81 (m, 1 H) 1.91 - 2.05 (m, 2 H) 2.24 - 2.34 (m, 1 H) 2.56 (s, 3 H) 2.89 - 3.10 (m, 2 H) 3.33 - 3.41 (m, 1 H) 3.58 (dd, 1 H) 4.41 - 4.46 (m, 1 H) 7.42 - 7.47 (m, 2 H) 7.58 (d, 1 H) 8.12 (dd, 1 H) 8.44 (d, 1 H) 8.80 - 8.87 (m, 2 H) 8.91 (s, 1 H) Example 2 : (lR,4R,6R)-3-{[6-methyl-3-(2-pyrimidinyl)-2-pyridinyl]carbonyl}-4-{2-[4- (trifluoromethyl)-2-pyridinyl]ethyl}-3-azabicyclo[4.1.0]heptanes (E2)

To a suspension of lithium 6-methyl-3-(2-pyrimidinyl)-2-pyridinecarboxylate D69 (108 mg and (lR,4R,6R)-4-{2-[4-(trifluoromethyl)-2-pyridinyl]ethyl}-3-azabicyclo[4.1.0]heptane D32 (33 mg) in dry DCM (1.5 ml), TBTU (47.0 mg, 0.147 mmol) and DIPEA (0.026 ml, 0.147 mmol) were added, then the suspension was stirred at room temperature for 2 hours. The mixture was quenched with NaHC0₃ saturated solution and extracted with DCM. Organic phase was dried over phase separator filter tube and concentrated under reduced pressure. Crude was loaded on a SCX cartridge washing with MeOH and eluting with NH₃ 2M in MeOH then purified by flash chromatography on KP-NH column (Biotage SP1, SNAP 1 lg, eluen Cy to Cy/EtOAc 0: 10) affording the title compound E2 (45 mg).

UPLC (Acid GEN QC SS) rtl = 0.85 minutes and rt2 = 0.91 min (rotamers present), peaks observed: 468 (M+l). C₂5H₂4F₃N₅0 requires 467.

1H NMR (400 MHz, CDC13) δ ppm 0.50-0.63 (m, 2H), 0.75-1.06 (m, 2H), 1.86-2.05 (m, 3H), 2.31-2.44 (m, 1H), 2.52-2.60 (s, 3H), 2.94-3.06 (m, 1H), 3.06-3.18 (m, 1H), 3.38-3.45 (m, 1H), 3.55-3.62 (dd, 1H), 4.61-4.70 (m, 1H), 7.08-7.14 (t, 1H), 7.14-7.20 (d, 1H), 7.25- 7.32 (d, 1H), 7.41-7.45 (s, 1H), 8.43-8.45 (d, 1H), 8.65-8.73 (m, 3H).

Example 3: (lR,4R,6R)-3-{[5-methyl-2-(2-pyrimidinyl)phenyl]carbonyl}-4-{2-[5- (trifluoromethyl)-2-pyridinyl]ethyl}-3-azabicyclo[4.1.0]heptane (E3)

(lR,4R,6R)-4-{2-[5-(trifluoromethyl)-2-pyridinyl]ethyl}-3-azabicyclo[4.1.0]heptane D23 (97 mg) was dissolved in DCM (3.2 ml). 5-methyl-2-(2-pyrimidinyl)benzoic acid (70 mg), DIPEA (0.063 ml, 0.359 mmol) and T₃P (0.661 ml, 1.111 mmol) were successively added. The resulting yellow solution was heated to reflux.

After 3 hours more 5-methyl-2-(2-pyrimidinyl)benzoic acid (70 mg, 0.327 mmol) and T₃P (313 ml) were added and the heating was maintained for additional 7 hours.

After this period the solvent was evaporated to dryness and the resulting dark brown sticky solid was dissolved in DMF (3.2 ml), a further amount of 5 -methyl -2-(2- pyrimidinyl)benzoic acid (70 mg) and T₃P (313 ml) were added and the resulting mixture was heated to 90 °C for 1 hour.

The reaction mixture was allowed to reach 23 °C, aqueous 1M NaOH (30 ml) and DCM (20 ml) were added. After the separation of the biphasic system, the aqueous layer was extracted with DCM (3 x 5 ml), the organic phase was filtered through a hydrophobic filter and evaporated under reduced pressure to give a dark oil.

It was purified by column chromatography (SNAP KP-NH 28g; Cy/iPrOH 5CV from 100% Cy to 95/5, 5CV 95/5).

After evaporation a brown oil, containing desired compound and other impurities, was obtained (100 mg).

It was sent purified by preparative chromatography (Achiral Purification Chromatography): fractions containing the title compound were joined together and the organic solvents were removed under reduced pressure.

To the remaining aqueous solution NaHC0₃ (50 ml)was added and it was back extracted with DCM (3 x 5 ml), filtered through a hydrophobic filter and evaporated under reduced pressure to give a yellow oil. This was purified by column chromatography (SNAP KP-Sil lOg; eluted with Cy/EtOAc

ICV from 50/50 to 30/70, ICV 30/70, ICV from 30/70 to 5/95, 10CV 5/95).

Evaporated fractions gave a white sticky solid, resulted to be the title compound E3 (15.4 mg).

UPLC (Basic GEN QC): rtl = 0.90 minutes and rt2 = 0.98 min (rotamers present), peaks observed: 467 (M+l). C26H25F3N4O requires 466.

1H NMR (500 MHz, DMSO-i¾) δ ppm 0.07 - 0.14 (m, 1 H) 0.59 - 0.65 (m, 1 H) 0.80 - 0.93 (m, 1 H) 0.93 - 1.11 (m, 1 H) 1.66 - 1.80 (m, 1 H) 1.88 - 2.12 (m, 2 H) 2.20 - 2.29 (m, 1 H) 2.40 (s, 3 H) 2.88 - 3.01 (m, 2 H) 3.36 - 3.40 (m, 2 H) 4.36 - 4.48 (m, 1 H) 7.06 - 7.11 (m, 1 H) 7.33 - 7.37 (m, 1 H) 7.39 - 7.42 (m, 1 H) 7.57 - 7.62 (m, 1 H) 7.93 - 8.16 (m, 2 H) 8.79 - 8.83 (m, 2 H) 8.92 - 8.96 (m, 1 H)

The compounds of Examples 4 to 15 were made using a method similar to that described for Example 3.

Amide coupling Characterising Data

Reactants

D33 and D69 (lR,4R,6R)-3-{[6-methyl-3-(2-pyrimidinyl)-2- pyridinyl]carbonyl}-4-{2-[4-(trifluoromethyl)-l,3- thiazol-2-yl]ethyl}-3-azabic clo [4.1.0] heptane

UPLC (Acid GEN QC SS) rtl = 0.87 minutes and rt2 = 0.93 min (rotamers present), peaks observed: 474 (M+l). C₂3H₂₂F₃N₅0S requires 473.

1H NMR (400 MHz, CDC13) δ ppm 0.58-0.68 (m, 2H), 0.84-0.92 (m, 1H), 0.97-1.13 (m, 1H), 1.98-2.04 (m, 2H), 2.11-2.21 (m, 1H), 2.43-2.57 (m, 1H), 2.62- 2.64 (s, 3H), 3.19-3.40 (m, 2H), 3.43-3.49 (m, 1H), 3.57-3.65 (m, 1H), 4.69-4.79 (m, 1H), 7.18-7.23 (m, 1H), 7.24-7.30 (m, 1H), 7.64-7.66 (s, 1H), 8.53-8.56 (d, 1H), 8.79-8.82 (d, 2H).

E5 D36 and D69 (lR,4R,6R)-3-{[6-methyl-3-(2-pyrimidinyl)-2- pyridinyl]carbonyl}-4-{2-[2-(trifluoromethyl)-4- pyrimidinyl]ethyl}-3-azabic clo [4.1.0] heptane

UPLC (Acid GEN QC SS) rtl = 0.83 minutes and rt2 = 0.87 min (rotamers present), peaks observed: 469 (M+l). C₂₄H₂3F₃N₆0 requires 468.

1H MR (400 MHz, CDC13) δ ppm 0.57-0.62 (m, IH), 0.62-0.67 (m, IH), 0.85-0.93 (m, IH), 0.98-1.12 (m, IH), 1.96-2.01 (m, 2H), 2.04-2.13 (m, IH), 2.49-

2.59 (m, IH), 2.62-2.65 (s, 3H), 3.06-3.22 (m, 2H),

3.42-3.49 (d, IH), 3.57-3.65 (dd, IH), 4.61-4.69 (m, IH), 7.18-7.21 (t, IH), 7.28-7.30 (d, IH), 7.55-7.58 (d, IH), 8.54-8.58 (d, IH), 8.74-8.77 (d, IH), 8.79-8.82 (d, 2H).

Ε6 D39 and D69 (lR,4R,6R)-3-{[6-methyl-3-(2-pyrimidinyl)-2- pyridinyl] carbonyl}-4-{2- [6-methyl-4- (trifluoromethyl)-3-pyridazinyl]ethyl}-3- azabicyclo [4.1.0] heptane

UPLC (Acid GEN_QC_SS) rtl = 0.77 minutes and rt2 = 0.84 min (rotamers present), peaks observed: 483 (M+l). C₂5H₂₅F₃N₆0 requires 482.

1H MR (400 MHz, CDC13) δ ppm 0.56-0.69 (m, 2H), 0.80-0.92 (m, IH), 0.96-1.06 (m, IH), 1.94-2.08 (m, 2H), 2.08-2.26 (m, IH), 2.43-2.57 (m, IH), 2.59- 2.64 (s, 3H), 2.80-2.85 (s, 3H), 3.19-3.33 (m, IH), 3.38-3.54 (m, 2H), 3.67-3.79 (dd, IH), 4.79-4.91 (m, IH), 7.15-7.21 (t, IH), 7.24-7.30 (d, IH), 7.48-7.54 (s, IH), 8.50-8.57 (d, IH), 8.70-8.80 (d, 2H).

E7 D 42 and D69 (lR,4R,6R)-3-{[6-methyl-3-(2-pyrimidinyl)-2- pyridinyl] carbonyl}-4-{2- [6-methyl-4- (trifluoromethyl)-2-pyridinyl]ethyl}-3- azabicyclo [4.1.0] heptane

UPLC (IPQC) rtl = 1.09 minutes and rt2 = 1.14 min (rotamers present), peaks observed: 482 (M+l).

C₂₆H₂₆F₃N₅O requires 481.

1H MR (400 MHz, CDC13) δ ppm 0.58-0.67 (m,

2H), 0.83-0.90 (m, 1H), 1.03-1.12 (m, 1H), 1.93-2.13

(m, 3H), 2.35-2.46 (m, 1H), 2.60-2.68 (m, 6H), 2.97- 3.07 (m, 1H), 3.07-3.17 (m, 1H), 3.45-3.50 (m, 1H), 3.62-3.68 (dd, 1H), 4.62-4.84 (m, 1H), 7.16-7.19 (m, 1H), 7.20-7.33 (m, 2H), 7.26-7.29 (m, 1H), 8.52-8.56 (d, 1H), 8.77-8.79 (d, 2H).

E8 D 45 and D71 (lR,4R,6R)-3-{[6-methyl-3-(2H-l,2,3-triazol-2-yl)- 2-pyridinyl]carbonyl}-4-{2-[5-(trifluoromethyl)- 1 ,3,4-thiadiazol-2-yl] ethyl}-3- azabicyclo [4.1.0] heptane

UPLC (IPQC) rtl = 1.05 minutes and rt2 = 1.12 min (rotamers present), peaks observed: 464 (M+l).

C₂₀H₂₀F₃N₇OS requires 463.

1H MR (400 MHz, CDC13) δ ppm 0.50-0.61 (m,

1H), 0.63-0.72 (m, 1H), 0.85-0.96 (m, 1H), 0.97-1.11 (m, 1H), 1.97-2.04 (m, 2H), 2.07-2.18 (m, 1H), 2.51- 2.60 (m, 1H), 2.61-2.65 (s, 3H), 3.18-3.64 (m, 4H), 4.70-4.80 (m, 1H), 7.30-7.33 (d, 1H), 7.83-7.85 (s, 2H), 8.21-8.26 (d, 1H).

E9 D19 and D71 (lR,4R,6R)-3-{[6-methyl-3-(2H-l,2,3-triazol-2-yl)-2- pyridinyl]carbonyl}-4-{2-[5-(trifluoromethyl)-2- pyridinyl] ethyl}-3-azabic clo [4.1.0] heptane

UPLC (Basic GEN QC): rtl = 0.87 minutes and rt2 = 0.92 min (rotamers present), peaks observed: 457 (M+l). C₂₃H₂₃F₃N₆0 requires 456.

1H MR (500 MHz, DMSO-i¾) δ ppm 0.40 - 0.51 (m, 1 H) 0.54 - 0.64 (m, 1 H) 0.86 - 0.93 (m, 1 H) 0.94 - 1.03 (m, 1 H) 1.75 - 1.84 (m, 1 H) 1.89 - 2.02 (m, 2 H) 2.22 - 2.33 (m, 1 H) 2.57 (s, 3 H) 2.79 - 3.05 (m, 2 H) 3.31 - 3.37 (m, 1 H) 3.56 (dd, 1 H) 4.31 - 4.45 (m, 1 H) 7.52 (d, 1 H) 7.55 (d, 1 H) 8.07 - 8.12 (m, 3 H) 8.22 (d, 1 H) 8.90 (s, 1 H) E10 D19 and D73 6,6'-dimethyl-2'-[((lR,4R,6R)-4-{2-[5- (trifluoromethyl)-2-pyridinyl]ethyl}-3- azabicyclo[4.1.0]hept-3-yl)carbonyl]-2,3'- bipyridine

UPLC (IPQC) rtl = 1.09 minutes and rt2 = 1.11 min (rotamers present), peaks observed: 481 (M+l).

C₂7H₂₇F₃N₄0 requires 480

1H MR (500 MHz, DMSO-i¾) δ ppm -0.01 - 0.13

(m, 1 H) 0.44 - 0.54 (m, 1 H) 0.80 - 0.97 (m, 2 H) 1.55 - 1.66 (m, 1 H) 1.81 - 2.00 (m, 2 H) 2.01 - 2.17 (m, 1 H) 2.42 - 2.47 (m, 3 H) 2.53 (s, 3 H) 2.58 - 2.73 (m, 1 H) 2.73 - 2.84 (m, 1 H) 3.18 - 3.26 (m, 1 H) 3.44 (dd, 1 H) 4.24 - 4.40 (m, 1 H) 7.16 - 7.52 (m, 2 H) 7.33 (d, 1 H) 7.38 - 7.45 (m, 1 H) 7.70 - 7.77 (m, 1 H) 7.92 - 8.01 (m, 2 H) 8.60 - 8.74 (m, 1 H)

Ell D22 and D69 (lR,4R,6R)-3-{[6-methyl-3-(2-pyrimidinyl)-2- pyridinyl]carbonyl}-4-{2-[3-(trifluoromethyl)-2- pyridinyl] ethyl}-3-azabicyclo [4.1.0] heptane

UPLC (Basic GEN QC): rtl = 0.86 minutes and rt2 = 0.91 min (rotamers present), peaks observed: 467

(M+l). C₂₅H₂4F₃N₅0 requires 468.

1H MR (500 MHz, DMSO-i¾) δ ppm 0.51 - 0.56 (m, 1 H) 0.57 - 0.62 (m, 1 H) 0.83 - 0.92 (m, 1 H) 0.93 - 1.03 (m, 1 H) 1.71 - 1.84 (m, 2 H) 1.85 - 2.03 (m, 1 H) 2.19 - 2.34 (m, 1 H) 2.55 (s, 3 H) 2.87 - 2.97 (m, 1 H) 3.06 - 3.15 (m, 1 H) 3.34 - 3.40 (m, 1 H) 3.57 - 3.65 (m, 1 H) 4.48 - 4.55 (m, 1 H) 7.33 - 7.53 (m, 3 H) 8.12 - 8.16 (m, 1 H) 8.43 (d, 1 H) 8.72 - 8.89 (m, 3 H)

E12 D25 and D71 (lR,4R,6R)-3-{[6-methyl-3-(2H-l,2,3-triazol-2-yl)-2- pyridinyl]carbonyl}-4-{2-[5-(trifluoromethyl)-2- pyrazinyl]ethyl}-3-azabic clo [4.1.0] heptane

UPLC (Final QC): rtl = 0.76 minutes and rt2 = 0.79 min (rotamers present), peaks observed: 458 (M+l). C₂₂H₂₂F₃N₇O requires 457.

1H MR (500 MHz, DMSO-i¾) δ ppm 0.42 - 0.52

(m, 1 H) 0.55 - 0.64 (m, 1 H) 0.85 - 0.94 (m, 1 H) 0.94 - 1.03 (m, 1 H) 1.69 - 1.84 (m, 1 H) 1.89 - 2.07 (m, 2 H) 2.28 - 2.39 (m, 1 H) 2.57 (s, 3 H) 2.90 - 3.10 (m, 2 H) 3.23 - 3.33 (m, 1 H) 3.57 (dd, 1 H) 4.34 - 4.44 (m, 1 H) 7.52 (d, 1 H) 8.08 - 8.13 (m, 2 H) 8.23 (d, 1 H) 8.79 (s, l H) 9.12 (s, 1 H)

E13 D25 (lR,4R,6R)-3-{[5-methyl-2-(2- And pyrimidinyl)phenyl] carbonyl}-4-{2- [5- (trifluoromethyl)-2-pyrazinyl]ethyl}-3-

N

azabicyclo [4.1.0] heptane

UPLC (Final QC): rtl = 0.77 minutes and rt2 = 0.84 minutes (rotamers present), peaks observed: 468 (M+l). C₂₅H₂₄F₃N₅O requires 467.

1H MR (500 MHz, DMSO-i¾) δ ppm 0.07 - 0.17 (m, 1 H) 0.58 - 0.67 (m, 1 H) 0.81 - 0.92 (m, 1 H) 0.95 - 1.10 (m, 1 H) 1.58 - 1.82 (m, 1 H) 1.90 - 2.10 (m, 2 H) 2.25 - 2.35 (m, 1 H) 2.39 (s, 3 H) 2.95 - 3.09 (m, 2 H) 3.41 - 3.50 (m, 1 H) 3.57 - 3.67 (m, 1 H) 4.35 - 4.49 (m, 1 H) 7.08 (s, 1 H) 7.28 - 7.47 (m, 2 H) 8.12 (d, 1 H) 8.69 - 8.93 (m, 3 H) 9.15 (s, 1 H)

E14 (lR,4R,6R)-3-{[6-methyl-3-(2-pyrimidinyl)-2-

D54 and D69 pyridinyl]carbonyl}-4-{2-[6-(trifluoromethyl)-2- pyrazinyl]ethyl}-3-azabic clo [4.1.0] heptane

L _/N. _/CF₃ UPLC (GEN QC SS): rtl = 0.84 minutes and rt2 =

N γ Y ³ 0.91 minutes (rotamers present), peaks observed: 469 ¾ o N (M+l) C₂₄H₂₃F₃N₆0 requires: 468.

1H NMR (500 MHz, DMSO-i¾) δ ppm 0.51 - 0.56 (m, 1 H) 0.57 - 0.63 (m, 1 H) 0.84 - 0.93 (m, 1 H) 0.96 - 1.05 (m, 1 H) 1.73 - 1.87 (m, 1 H) 1.92 - 2.08 (m, 2 H) 2.16 - 2.40 (m, 1 H) 2.56 (s, 3 H) 3.00 - 3.09 (m, 2 H) 3.33 - 3.41 (m, 1 H) 3.53 - 3.61 (m, 1 H) 4.40 - 4.46 (m, 1 H) 7.41 - 7.48 (m, 2 H) 8.45 (d, 1 H) 8.82 - 8.87 (m, 2 H) 8.97 (s, 1 H) 9.03 (s, 1 H)

Example 16: (lS,4R,6S)-3-{[6-methyl-3-(2-pyrimidinyl)-2-pyridinyl]carbonyl}-4-{2-[5- (trifluoromethyl)-2-pyrazinyl]ethyl}-3-azabicyclo[4.1.0]heptane (D16)

To a suspension of (lS,4R,6S)-4-{2-[5-(trifluoromethyl)-2-pyrazinyl]ethyl}-3- azabicyclo[4.1.0]heptane D20 (45 mg), 6-methyl-3-(2-pyrimidinyl)-2-pyridinecarboxylic acid D69 (119 mg), DIPEA (0.087 ml, 0.498 mmol) in DCM (5 ml) was added TBTU (61.8 mg, 0.192 mmol) in one portion. The mixture was stirred at room temperature for 2 hours. The reaction was quenched with a saturated solution of NaHC0₃ (15 ml), the aqueous phase was extracted with DCM (3x 10 ml) and the j oined organic phase was washed with water (3x20 ml), dried using a phase separator tube and concentrated to give 95 mg of crude. This was purified by flash chromatography (Si cartridge 5 g, cyclohexane:2-propanol 95:5 and cyclohexane:2-propanol 90: 10), the appropriated fraction were joined and concentrated to obtain 45 mg.

This was loaded onto SCX cartridge (2 g) eluting with MeOH and ammonia (2.0 M) in MeOH. The ammoniacal fraction was evaporated to give the title compound E16 (37 mg). UPLC (Final QC): rtl = 0.79 minutes and rt2 = 0.83 minutes (rotamers present) peaks observed: 469 (M+l) C₂₄H₂₃F₃N₆0 requires: 468.

1H MR (400 MHz, DMSO-d6) d ppm 0.18 - 0.26 (m, 1 H) 0.61 - 0.70 (m, 1 H) 0.89 -

1.35 (m, 3 H) 1.86 - 2.28 (m, 2 H) 2.29 - 2.73 (m, 5 H) 2.91 - 3.13 (m, 2 H) 3.53 - 3.65 (m, 1 H) 4.00 - 4.12 (m, 1 H) 7.38 - 7.48 (m, 2 H) 8.42 - 8.49 (m, 1 H) 8.78 - 8.85 (m, 3 H) 9.05 - 9.15 (m, 1 H) Example 17: (lR,4R,6R)-4-[2-(5,6-dimethyl-l,2,4-triazin-3-yl)ethyl]-3-{[6-methyl-3-(2- pyrimidinyl)-2-pyridinyl] carbonyl}-3-azabic clo [4.1.OJheptanes (E 17)

Example 18: Determination of antagonist affinity at human Orexin-1 and 2 receptors using FLIPR Cell Culture

Adherent Chinese Hamster Ovary (CHO) cells, stably expressing the recombinant human Orexin-1 or human Orexin-2 receptors or Rat Basophilic Leukaemia Cells (RBL) stably expressing recombinant rat Orexin-1 or rat Orexin-2 receptors were maintained in culture in Alpha Minimum Essential Medium (Gibco/Invitrogen, cat. no.; 22571-020), supplemented with 10% decomplemented foetal bovine serum (Life Technologies, cat. no. 10106-078) and 400 μg/mL Geneticin G418 (Calbiochem, cat. no.345810). Cells were grown as monolayers under 95%:5% air:C0₂ at 37 °C.

The sequences of the human orexin 1, human orexin 2, rat orexin 1 and rat orexin 2 receptors used to test the compounds of examples 1 to 16 were as published in Sakurai, T. et al (1998) Cell, 92 pp 573 to 585.

Measurement of [C^J, using the FLIPR™

Cells were seeded into black clear-bottom 384-well plates (density of 20,000 cells per well) in culture medium as described above and maintained overnight (95%:5% air:C0₂ at 37°C). On the day of the experiment, culture medium were discarded and the cells washed three times with standard buffer (NaCl, 145 mM; KC1, 5 mM; HEPES, 20 mM;

Glucose, 5.5 mM; MgCl₂, 1 mM; CaCl₂, 2 mM) added with Probenecid 2.5 mM. The plates were then incubated at 37 °C for 60 minutes in the dark with 2 μΜ FLUO-4AM dye to allow cell uptake of the FLUO-4AM, which is subsequently converted by intracellular esterases to FLUO-4, which is unable to leave the cells. After incubation, cells were washed three times with standard buffer to remove extracellular dye and 30 μΕ of buffer were left in each well after washing.

Compounds of the invention were tested in a final assay concentration range from

1.66xlO^"5M to 1.58xl0^"uM. Compounds of the invention were dissolved in

dimethylsulfoxide (DMSO) at a stock concentration of 10 mM. These stock solutions were serially diluted with DMSO and 1 μL· of each dilution was transferred to a 384 well compound plate. Immediately before introducing compound to the cells, buffer solution (50 μΐ/well) was added to this plate. To allow agonist stimulation of the cells, a stock plate containing a solution of human orexin A (hOrexin A) was diluted with buffer to final concentration just before use. This final concentration of hOrexin A was equivalent to the calculated EC80 for hOrexinA agonist potency in this test system. This value was obtained by testing hOrexinA in concentration response curve (at least 16 replicates) the same day of the experiment.

The loaded cells were then incubated for lOmin at 37°C with test compound. The plates were then placed into a FLIPR™ (Molecular Devices, UK) to monitor cell fluorescence (Xg_X = 488nm, λ_ΕΜ = 540nm) (Sullivan E, Tucker EM, Dale IL. Measurement of [Ca²⁺]i using the fluometric imaging plate reader (FLIPR). In: Lambert DG (ed.), Calcium Signaling Protocols. New Jersey: Humana Press, 1999, 125-136). A baseline fluorescence reading was taken over a 5 to 10 second period, and then 10 μΕ of EC80 hOrexinA solution was added. The fluorescence was then read over a 4-5 minute period.

Data Analysis

Functional responses using FLIPR were measured as peak fluorescence intensity minus basal fluorescence and expressed as a percentage of a non-inhibited Orexin-A- induced response on the same plate. Iterative curve-fitting and parameter estimations were carried out using a four parameter logistic model and Microsoft Excel (Bowen WP, Jerman JC. Nonlinear regression using spreadsheets. Trends Pharmacol. Sci. 1995; 16: 413-417). Antagonist affinity values (IC₅₀) were converted to functional pIQ values using a modified Cheng-Prusoff correction (Cheng YC, Prusoff WH. Relationship between the inhibition constant (IQ) and the concentration of inhibitor which causes 50 percent inhibition (IC₅₀) of an enzymatic reaction. Biochem. Pharmacol. 1973, 22: 3099-3108).

Where [agonist] is the agonist concentration, EC₅₀ is the concentration of agonist giving 50% activity derived from the agonist dose response curve and n=slope of the dose response curve. When n=l the equation collapses to the more familiar Cheng-Prusoff equation.

Compounds of examples 1 to 16 were tested according to the method of example 18. All compounds gave fpKi values from 5.9 to 9.1 at the human cloned orexin- 1 receptor and from 5.8 to 7.4 at the human cloned orexin-2 receptor with the exception that the compounds of Example 6: (lR,4R,6R)-3-{[6-methyl-3-(2-pyrimidinyl)-2- pyridinyl]carbonyl}-4-{2-[6-methyl-4-(trifluoromethyl)-3-pyridazinyl]ethyl}-3- azabicyclo[4.1.0]heptanes, and Example 8: (lR,4R,6R)-3-{[6-methyl-3-(2H-l,2,3-triazol-2- yl)-2-pyridinyl]carbonyl}-4-{2-[5-(trifluoromethyl)-l,3,4-thiadiazol-2-yl]ethyl}-3- azabicyclo[4.1.OJheptanes showed activity at the orexin 2 receptor which was below 5.5.

Claims

Claims

1. A compound of formula (I)

(I)

wherein:

Het is a heteroaryl group selected from pyridinyl, pyrimidinyl, pyridazinyl, pyrazinyl, triazinyl, thiazolyl or thiadiazolyl, said heteroaryl group being optionally substituted with 1, 2 or 3 substituents independently selected from the group consisting of: Ci_-4alkyl, halo, Ci. ₄alkoxy, haloCi_-4alkyl, haloCi_-4alkoxy and cyano;

X is C or N;

Y is C or N;

Ri is Ci_-4alkyl, halo, Ci_-4alkoxy, haloCi_-4alkyl, haloCi_-4alkoxy, cyano, Ci_-4alkylS0₂, C_3-8 cycloalkylS0₂, C_3-8cycloalkylCH₂S0₂, phenyl or a 5 or 6 membered heterocyclyl group containing 1, 2 or 3 atoms selected from N, O or S, which phenyl or heterocyclyl group is optionally substituted with Ci_-4alkyl, halo, Ci_-4alkoxy, haloCi_-4alkyl, haloCi_-4alkoxy or cyano;

R₂ is Ci_-4alkyl, halo, Ci_-4alkoxy, haloCi_-4alkyl, haloCi_-4alkoxy, cyano, phenyl or a 5 or 6 membered heterocyclyl group containing 1, 2 or 3 atoms selected from N, O or S, which phenyl or heterocyclyl group is optionally substituted with Ci_-4alkyl, halo, Ci_-4alkoxy, haloCi_-4alkyl, haloCi_-4alkoxy or cyano;

R₃ is Ci_-4alkyl, halo, Ci_-4alkoxy, haloCi_-4alkyl, haloCi_-4alkoxy or cyano;

m is 0 or 1; and

n is 0 or 1;

or a pharmaceutically acceptable salt thereof.

2. A compound according to claim 1 where the stereogenic centres of the compounds of formula (I) are in a cis (\S,4R,6S)- configuration, or a pharmaceutically acceptable salt thereof.

3. A compound according to claim 1 where the stereogenic centres of the compounds of formula (I) are in a trans (\R,4R,6R)- configuration, or a pharmaceutically acceptable salt thereof.

4. A compound according to any one of claims 1 to 3 where Het is pyridinyl, or a pharmaceutically acceptable salt thereof.

5. A compound according to any one of claims 1 to 3 where Het is pyrimidinyl, or a pharmaceutically acceptable salt thereof.

6. A compound according to any one of claims 1 to 3 where Het is pyridazinyl, or a pharmaceutically acceptable salt thereof.

7. A compound according to any one of claims 1 to 3 where Het is pyrazinyl, or a pharmaceutically acceptable salt thereof.

8. A compound according to any one of claims 1 to 3 where Het is thiazolyl, or a pharmaceutically acceptable salt thereof.

9. A compound according to any one of claims 1 to 3 where Het is thiadiazolyl, or a pharmaceutically acceptable salt thereof.

10. A compound of formula (I) selected from the group consisting of:

(lR,4R,6R)-3-{[6-methyl-3-(2-pyrimidinyl)-2-pyridinyl]carbonyl}-4-{2-[5- (trifluoromethyl)-2-pyridinyl] ethyl } -3 -azabicyclo[4.1. OJheptane;

(lR,4R,6R)-3-{[6-methyl-3-(2-pyrimidinyl)-2-pyridinyl]carbonyl}-4-{2-[4- (trifluoromethyl)-2-pyridinyl] ethyl } -3 -azabicyclo[4.1. OJheptanes;

(lR,4R,6R)-3-{[5-methyl-2-(2-pyrimidinyl)phenyl]carbonyl}-4-{2-[5-(trifluoromethyl)-2- pyridinyl] ethyl } -3 -azabicyclo[4.1.OJheptane;

(lR,4R,6R)-3-{[6-methyl-3-(2-pyrimidinyl)-2-pyridinyl]carbonyl}-4-{2-[4- (trifluorom ethyl)- 1 ,3 -thiazol-2-yl]ethyl } -3-azabicyclo[4.1.OJheptane;

(lR,4R,6R)-3-{[6-methyl-3-(2-pyrimidinyl)-2-pyridinyl]carbonyl}-4-{2-[2- (trifluoromethyl)-4-pyrimidinyl]ethyl}-3-azabicyclo[4.1. OJheptane;

(lR,4R,6R)-3-{[6-methyl-3-(2-pyrimidinyl)-2-pyridinyl]carbonyl}-4-{2-[6-methyl-4- (trifluoromethyl)-3-pyridazinyl]ethyl}-3-azabicyclo[4.1. OJheptane;

(lR,4R,6R)-3-{[6-methyl-3-(2-pyrimidinyl)-2-pyridinyl]carbonyl}-4-{2-[6-methyl-4- (trifluoromethyl)-2-pyridinyl] ethyl } -3 -azabicyclo[4.1.OJheptane;

(lR,4R,6R)-3-{[6-methyl-3-(2H-l,2,3-triazol-2-yl)-2-pyridinyl]carbonyl}-4-{2-[5- (trifluorom ethyl)- 1 ,3 ,4-thiadiazol-2-yl]ethyl } -3-azabicyclo[4.1.OJheptane;

(lR,4R,6R)-3-{[6-methyl-3-(2H-l,2,3-triazol-2-yl)-2-pyridinyl]carbonyl}-4-{2-[5- (trifluoromethyl)-2-pyridinyl] ethyl } -3 -azabicyclo[4.1. OJheptanes;

6,6'-dimethyl-2'-[((lR,4R,6R)-4-{2-[5-(trifluoromethyl)-2-pyridinyl]ethyl}-3- azabicyclo[4.1.0]hept-3-yl)carbonyl]-2,3'-bipyridine;

(lR,4R,6R)-3-{[6-methyl-3-(2-pyrimidinyl)-2-pyridinyl]carbonyl}-4-{2-[3- (trifluoromethyl)-2-pyridinyl]ethyl}-3-azabicyclo[4.1. OJheptanes;

(lR,4R,6R)-3-{[6-methyl-3-(2H-l,2,3-triazol-2-yl)-2-pyridinyl]carbonyl}-4-{2-[5- (trifluoromethyl)-2-pyrazinyl]ethyl}-3-azabicyclo[4.1.OJheptane;

(lR,4R,6R)-3-{[5-methyl-2-(2-pyrimidinyl)phenyl]carbonyl}-4-{2-[5-(trifluoromethyl)-2- pyrazinyl]ethyl}-3-azabicyclo[4.1.OJheptane; (lR,4R,6R)-3-{[6-methyl-3-(2-pyrimidinyl)-2-pyridinyl]carbonyl}-4-{2-[6- (trifluoromethyl)-2-pyrazinyl]ethyl}-3-azabicyclo[4.1.0]heptane;

(lR,4R,6R)-4 2 5,6-dimethyl-2-pyrazinyl)ethyl]-3-{[6-methyl-3 2H-l,2,34riazol-2-y pyridinyl]carbonyl}-3-azabicyclo[4.1.0]heptane;

(lS,4R,6S)-3-{[6-methyl-3-(2-pyrimidinyl)-2-pyridinyl]carbonyl}-4-{2-[5- (trifluoromethyl)-2-pyrazinyl]ethyl}-3-azabicyclo[4.1.0]heptane; and

(lR,4R,6R)-4 2 5,6-dimethyl-l,2,4-triazin-3-yl)ethyl]-3-{[6-methyl-3-(2-pyrimidinyl)-2- pyridinyl]carbonyl}-3-azabicyclo[4.1.0]heptanes;

or a pharmaceutically acceptable salt thereof.

11. The compound as defined in any one of claims 1 to 10, or a pharmaceutically acceptable salt thereof, for use in therapy.

12. The compound as defined in any one of claims 1 to 10, or a pharmaceutically acceptable salt thereof, for use in the treatment of a disease or disorder where an antagonist of a human orexin receptor is required.

13. The compound according to claim 12, or a pharmaceutically acceptable salt thereof, wherein the disease or disorder is a sleep disorder, a depression or mood disorder, an anxiety disorder, a substance-related disorder or a feeding disorder.

14. The compound according to claim 13, or a pharmaceutically acceptable salt thereof, wherein the disease or disorder is a sleep disorder.

15. A pharmaceutical composition comprising a) the compound as defined in any one of claims 1 to 10, or a pharmaceutically acceptable salt thereof, and b) one or more

pharmaceutically acceptable carriers.