Organic compounds
The present invention relates to compounds that inhibit cellular adhesion. More particularly, the present invention relates to sialyl Lewis X mimetics which mimic the inhibition of selectin-mediated cellular adhesion by sialyl Lewis X.
The complex process of inflammation, which takes place in several stages, is the body's natural reaction to injuries in which, for example, there is also invasion by infectious agents. Under the influence of cytokines, the endothelium which lines the blood vessels expresses adhesion proteins on its surface. The P and E selectins bring about, by a protein-carbohydrate interaction with glycolipids and glycoproteins on the leukocyte membrane, the so- called "rolling" of leukocytes. The latter are slowed down by this process, and there is activation of certain proteins (integrins) on their surface which ensure firm adhesion of the leukocytes to the endothelium. This is followed by migration of the leukocytes into the damaged tissue.
There are many situations in which the recruitment of leukocytes by adhesion to the endo- thelial cells is abnormal and in excess resulting in tissue damage instead of repair. This is the case in disorders such as cardiogenic shock, myocardial infarct, thrombosis, rheumatism, psoriasis, arthritis, dermatitis, acute respiratory distress syndrome, metastatic cancer and transplantation.
One of the smallest natural carbohydrate epitopes as ligand for E selectin is sialyl-Lewis X [neuraminic acid-α(2→3)-D-galactose-β(1 →4)-L-(fucose-α(1 →3))-N-acetyl-D-glucosamine (sLex)]. Although it has been considered to be potentially useful as an antiinflammatory agent it can only be used as an injectable form as it is orally inactive and has a short half- life in blood. Thus, there is a need for compounds which prevent the interaction between P and E selectins and their receptors on the leukocyte membrane and which prevent the initial cellular adhesion process.
What are needed are SLex mimetics which are easy to synthesize, more stable and more active than SLe", and preferably orally active.
The present invention relates to compounds of formula I
(a) R1 is CH3;
Y is Cι-C4alkylene which is unsubstituted or substituted by one or two substituents selected from OR3 and C(O)NH[CH2]mC(O)NHC10-C16alkyl; R2 is -NR6R7; R3 is aralkyi with Cι-C6alkyl and C6-Cι0aryl or CH- OJNHCi-C∑oal yI which is unsubstituted or substituted by one or two OC(O)Cι0-Cι6alkyl;
R6 is C(O)CHR8NHC(O)(CH2)qC(O)OH;
R7 is H or (CH2)mC(O)NHC10-Cι6alkyl; R8 s d-Cβalkyl unsubstituted or substituted with one or two OH; m s a number from 1 to 6; and q s 2 or 3; or
(b) R1 s OH;
Y s -CH2-;
R2 s -NR6H; and
R6 s C(O)-C,-C3oalkyl which is substituted by C(O)OH; or (c) R1 s a group of formula la
Y is -CH2-; and R2 is OH; or (d) R1 is Y*-R2';
Y is -CH2-;
R2 is OH, -O-C4-C3oalkyl or NHR6;
Y' is -CH2- or -O-CH2-;
R2' is -CHOHCHOHC(O)(CH2)nR5; -CHOHCHOHC(O)[CH2]nC(O)OH;
-CHOHCHOHC(O)CH2CH[benzyl]C(O)OH; -CHOHCHOHC(O)NH(CHR4)nC(O)OH; -C(O)NHCH2C(O)OH; C(O)NHCHR4C(O)OH; -C(O)NHC2-C4alkyl which is substituted by two C(O)OH or -C(O)NHphenyl which is substituted by one C(O)OH;
R4 is H, d-C6alkyl which is substituted by C(O)OH; CH2hydroxyphenyl or benzyl;
R5 is OPO3H2 or PO3H2;
R6 is C4-C3oalkyl which is unsubstituted or substituted by CB-Cι0aryl, aralkyi with d- C6alkyl and C6-C10aryl, O-C -C-*-oalkyl which is unsubstituted or substituted by C6- C10aryl, O-C4-C30alkenyl with 1 to 3 double bonds, O-C6-C10aryl, C(O)-d-C30alkyl which is unsubstituted or substituted by C6-Cι0aryl or C(O)OH, C(O)-C4-C*3oalkenyl with 1 to 3 double bonds, C(O)(CHR8)pNHC(O)(CH2)qC(O)OH, C(O)(CH2)mNHd- C6alkyl, or C(O)(CH2)rCON(CH2CONH(CH2)CH3)HCONH(CH2)sCH3;
R8 is H or d-C6alkyl unsubstituted or substituted with one or two OH; m is a number from 1 to 6; n is 1 or 2; and the sum of p and q as well as of r and s has a value of from 2 to 22; including their physiologically tolerated salts.
The compounds of formula I may comprise one or more asymmetric carbon atoms. It will be understood that the present invention includes all individual isomeric forms, enantiomers and diastereoisomers as well as mixtures, e.g. racemates, unless otherwise stated.
A preferred embodiment comprises compounds of group (a) wherein R
1 is CH
3; Y is d- dalkylene which is substituted by one or two OR
3; R
2 is -NHR
6; R
3 is aralkyi with d-C
6alkyl and C
6-Cι
0aryl or
which is unsubstituted or substituted by one or two OC(O)C
10-Cιβalkyl; R
6 is C(O)(CHR
8)
pNHC(O)(CH
2)
c,C(O)OH; R
8 is Cι-C
6aikyl unsubstituted or substituted with one or two OH; p is 1 ; and q is 2 or 3. Most preferred compounds are 1 , 2, 3b, 4, 5b and 6b as exemplified in Examples B.
Another preferred embodiment comprises compounds of group (a) wherein R1 is CH3; Y is CrC alkylene which is substituted by one or two OR3; R2 is -NR6R7; R3 is aralkyi with C C6alkyl and C6-Cι0aryl or CH2C(O)NHd-C2oalkyl which is unsubstituted or substituted by one or two OC(O)C10-C16alkyl; R6 is C(O)(CHR8)pNHC(O)(CH2)<,C(O)OH; R7 is (CH2)mC(O)NHC10-C16alkyl; R8 is d-C6alkyl unsubstituted or substituted with one or two OH;
p is 1 ; and q is 2 or 3. Most preferred compounds are 7, 8 and 79(3) as exemplified in Examples B.
Within group (b) the most preferred compounds are 27(15) and 29(15) as exemplified in Examples B.
Within group (c) the most preferred compounds are 19(15), 24(15) and 1(3) as exemplified in Examples B.
Another preferred embodiment comprises compounds of group (d) wherein R1 is Y'-R2 ; Y is -CH2-; Y' is -CH2- or -O-CH2-; R2 is OH; R2' is CHOHCHOHC(O)(CH2)nR5; R5 is OPO3H2 or PO3H2; and n is 1 or 2. Most preferred compounds are 6(14), 4(3), 4a(3), 7(14) and 13(14) as exemplified in Examples B.
Another preferred embodiment comprises compounds of group (d) wherein R1 is Y'-R2; Y is -CH2-; R2 is OH; Y' is -CH2-; R2' is -CHOHCHOHC(O)(CH2)2C(O)OH; -CHOHCHOHC(O)CH2CH[benzyI]C(O)OH; -CHOHCHOHC(O)NHCHR C(O)OH; -C(O)NHCH2C(O)OH or C(O)NHCHR C(O)OH; and R4 is H, C,-C6alkyl which is substituted by C(O)OH; CH2hydroxyphenyl or benzyl. Most preferred compounds are 5(15), 6(15), 102(3), 103(3), 104(3), 105(3) and 106(3) as exemplified in Examples B.
Another preferred embodiment comprises compounds of group (d) wherein R1 is Y'-R2; Y is -CH2-; Y' is -CH2-; R2 is -O-d-doalkyl and R is -C(O)NHC2-dalkyl which is unsubstituted or substituted by two C(O)OH; or -C(O)NHphenyl which is substituted by one C(O)OH. Most preferred compounds are 3(3) and 3a(3) as exemplified in Examples B.
Another preferred embodiment comprises compounds of group (d) wherein R1 is Y'-R2 ; Y is -CH2-; Y* is -CH2- or -O-CH2-; R2 is -NHR6; R2' is - CHOHCHOHC(O)CH2R5 or C(O)NHCHR4C(O)OH; R5 is OPO3H2 or PO3H2; R6 is C4-C3oal yl which is unsubstituted or substituted by C6-C10aryl, aralkyi with Cι-C6alkyl and C6-Cιoaryl, O- -Csoalkyl; C(O)-d- Csoalkyl which is unsubstituted or substituted by C6-C10aryl or C(O)OH; C(O)(CH2)pNHC(O)(CH2)qC(O)OH; C(O)(CH2)rnNHC,-C6alkyl; or C(O){CH2)rCON(CH2CONH(CH2)CH3)HCONH(CH2)sCH3; m is a number from 1 to 6; n is 1 or
2; and the sum of p and q as well as of r and s has a value of from 2 to 22. Most preferred compounds are 39(3)-58c(3), 69(3) and 72(3) as exemplified in Examples B.
The present invention also comprises a process for the preparation of the compounds of the formula I wherein the corresponding radicals -Y-R2 and -Y'-R* are coupled, optionally via more than one step, to the corresponding sugar moiety. The procedures are generally known to the skilled person or can be deduced from the Examples, describing further non- limiting details of the preparation. Of particular interest is the coupling step within the synthesis of C-glycosides of group (d), eg. 6(14) and 4(3) which may be performed in the presence of a DHAP dependent aldolase. In a preferred mode, the DHAP substrate is a compound selected from the group consisting of e.g. dihydroxyacetone phosphate and 3- keto-4-hydroxy-butanyl-1-phosphonate. In an alternative preferred mode, the DHAP dependent aldolase is selected from the group consisting of FDPA, FucA, RhaA and TagA.
The compounds of formula I exhibit valuable pharmacological properties as indicated in tests and are therefore indicated for therapy. In particular the compounds of formula I inhibit the binding of E-selectin to HL-60 cells as disclosed in Example D.
The compounds are particularly indicated for preventing or treating conditions or diseases which are mediated by the binding of selectin in cellular adhesion, e.g. acute or chronic inflammatory or autoimmune diseases such as rheumatoid arthritis, asthma, allergy conditions, psoriasis, contact dermatitis, adult respiratory distress syndrome, inflammatory bowel disease and ophthalmic inflammatory diseases, infection diseases such as septic shock, traumatic shock, thrombosis and inappropriate platelet aggregation conditions, cardiovascular diseases such as heart attacks, reperfusion injury, multiple sclerosis and neoplastic diseases including metastasis conditions, strokes and acute or chronic rejection of organ or tissue transplants.
Acute and chronic rejection play a role in the transplantation of organs or tissues from a donor to a recipient of the same species (allograft) or different species (xenograft). Among such transplanted organs or tissues and given illustratively are heart, lung, combined heart- lung, trachea, liver, kidney, spleen, pancreatic (complete or partial, e.g. Langerhans islets), skin, bowel, or cornea or a combination of any of the foregoing.
For the above uses the required dosage will of course vary depending on the mode of administration, the particular condition to be treated and the effect desired, In general, however, satisfactory results are achieved at dosage rates of from 0.1 to about 100 mg kg/day, administered in 1 , 2, 3, or 4 doses/day, or in sustained release form. Suitable daily dosages for oral administration to larger mammals, e.g., humans, are generally about 50 to 1500 mg, preferably in the order of from 200 to 800 mg. Unit dosage forms suitably comprise from about 25 mg to 0.750 g of a compound of the invention, together with a pharmaceutical acceptable diluent or carrier therefor.
The compounds of formula I may be administered by any conventional route of administration, e.g. enterally, preferably orally, e.g. in the form of tablets or capsules, or par- enterally e.g. in form of injectable solutions or suspensions.
OPO3H2, PO3H2 and the carboxyl group may be in free acid form or in salt form. Pharmaceutically acceptable salts are to be understood as meaning, in particular, the alkali metal and alkaline earth metal salts, for example sodium, potassium, magnesium and calcium salts. Sodium and potassium ions and their salts are preferred.
In accordance with the foregoing the present invention further provides:
(a) a compound of formula I or a pharmaceutically acceptable salt thereof for use as a pharmaceutical;
(b) a method for preventing or treating conditions or diseases as indicated above in a subject in need of such treatment, which method comprises administering to said subject an effective amount of a compound of formula I or a pharmaceutically acceptable salt thereof;
(c) a pharmaceutical composition comprising a pharmaceutically effective amount of the compound of formula I or a pharmaceutically acceptable salt thereof together with a pharmaceutically acceptable diluent or carrier;
(d) a compound of formula I or a pharmaceutically acceptable salt thereof for use in the manufacturing of a medicament for use in the method as in (b) above.
The compound may be administered alone or in combination with one or more other anti-inflammatory or immunosuppressive agents, for example in combination with cyclosporin A and analogs thereof, FK-506 and analogs thereof, rapamycin and analogs thereof, myco-
phenolic acid, mycophenolate mofetil, mizoribine, 15-deoxyspergualine, leflunomide, steroids, cyclophosphamide, azathioprene (AZA), or anti-lymphocyte antibodies or immuno- toxins such as monoclonal antibodies to leukocyte receptors, e.g. MHC, CD2, CD3, CD4, or CD25; especially in combination with a T-cell suppressant, e.g., cyclosporin A or FK-506. Such combination therapy is further comprised within the scope of the invention, e.g., a method according to 1 above further comprising administration concomitantly or in sequence of a therapeutically or synergistically effective amount of such a second immunosuppressive or anti-inflammatory agent.
The following examples are offered as a way for illustration of this invention and not in a way of limitation.
Abbreviations used: BnBr: benzyl bromide; CSA: camphorsulfonic acid; DCM: dichloromethane; DEAD: diethylazodicarboxylate; C-DHAP: 3-keto-4-hydroxy-butanyl-1-phos- phonate; DHAP: dihydroxyacetone phosphate; dppb: 1 ,4-bis(diphenylphosphino)butane; DMAP: 4-dimethylaminopyridine; DMF: dimethylformamide; DMS: dimethylsulfide; EDC: 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride; ESI: electrospray ionization; HOBt: 1-hydroxybenzotriazole; HOSu: N-hydroxy succinimide; NBA: m-nitrobenzylalcohol; NMM: 4-methyl morpholine; PPh3: triphenylphosphine; RT: room temperature; SGCC: silica gel column chromatography; TBAF: tertbutylammonium fluoride; TBAI: tetrabutylammonium iodide; THF: tetrahydrofuran; TMSOTf: trimethylsilyltriflate
Examples
General procedures
Hydrogenation of Mannose Based Mimetics: To a stirred solution of the amide in 2 ml of
HOAc is added 2 drops of H2O, a catalytic amount of 10% Pd/C and H2 gas. After stirring for 1 day, the catalyst is filtered off through a pad of celite and the pad is rinsed with HOAc.
The filtrate is concentrated under reduced pressure to provide a white solid or a colorless oil. After lyophilization this product is a white hygroscopic solid.
Coupling a Carboxylic Acid and an Amine: To a stirred 0°C solution of the carboxylic acid
(1.0 mmol), HOBt (1.2 mmol), the amine (2.0 mmol) and NMM (2.5 mmol) in CH2CI2 [0.5 M] is added EDC (1.3mmol). After stirring overnight and subsequent warming to RT, tic analysis indicates complete consumption of the starting acid. Sat. NaHCO3 soln. and CH2CI2 are added to the reaction mixture. The aqueous portion is extracted twice with CH2CI2. The
combined organic fractions are washed with 1N HCI and brine, dried over Na2SO4 and concentrated. The crude residue is purified by flash chromatography in silica gel using ethyl acetate/hexane as the eluent.
Removal of Boc Group: The Boc compound (1.0 mmol) is dissolved in a 50:50 mixture of CH2CI2:TFA and the mixture is cooled to 0°C. After 30 min, tic analysis indicates the complete consumption of the starting material. The residue is concentrated to remove the excess TFA and CH2CI2 and the residue is rinsed with CHCI3 and concentrated to remove any traces of TFA. The TFA amine salt is the one used in the general procedure for coupling a carboxylic acid and an amine, using an additional equivalent of NMM. Succinate Anhydride Coupling: To a stirred solution of succinic anhydride (1.0 mmol; alternatively can use glutaric anhydride) and amine (1.1 mmol) in methylene chloride (0.5 M) is added NMM (1.1 mmol). After stirring overnight, the reaction is quenched with brine and methylene chloride. Aqueous portion is extracted with methylene chloride. Combined organics are dried with sodium sulfate and concentrated. The crude residue is purified by flash chromatography on silica gel using ethylacetate/hexanes as the solvent mixture. Asymmetric dihydroxylation (AD-reaction). The diols are prepared from the unsaturated esters according to the literature protocol as follows: A solution of AD-mix (α or β) (1.4 g/mmol olefin) in tert.-butanol (5 ml) and H2O (5 ml) is cooled to 0°C, MeSO2NH2 and the olefin (1 mmol) are added and the heterogeneous mixture is stirred at 4°C until completion is indicated by tic (up to 48 h, to avoid very slow conversion, addition of extra potassium osmate (1.3 mg) is recommended). Sodium sulfite (1.5 g) is added at 4°C and stirring is continued at 23°C for 30 min. Triple extraction with EtOAc is followed by washings with 1 N NaOH and brine. After drying over Na2SO4 and removal of the solvent in vacuo the residual slightly yellow solid is purified by SGCC (gradient elution EtOAc in hexanes) to give the desired diol.
Peptide coupling with EDC/HOBt: GP A: A solution of the amine, HOBt, the carboxylic acid and NMM in dry DMF is cooled to -20°C and EDC is added in one portion. The reaction mixture is stirred at -20°C for 1 h and then allowed to reach 23°C slowly. After 16 to 36 h the reaction is taken up in ethyl acetate and extracted with 5% w/v citric acid solution (20 ml). The aqueous layer is further extracted with ethyl acetate (4 x 20 ml) and the combined organic layers are washed with sat. NaHCO3-sol. (40 ml) and brine (40 ml) followed by drying over MgSO4. After evaporation under reduced pressure the residual oil is purified by
silica gel column chromatography (gradient elution with 30%→100% EtOAc in hexanes) to give the coupled compound.
GP B: A solution of the amine, HOBt, the carboxylic acid and NMM in dry CH2CI2 is cooled to 0°C and EDC is added in one portion. The reaction mixture is stirred several h at 0°C and then allowed to reach 23°C slowly. After 4 to 18 h the reaction is worked up as described above in GP A.
Final deprotection by hydrogenolysis: GP A: A solution of the benzyl protected compound in 80% aq. HOAc is hydrogenated at 1 atm in the presence of Pd/C (10% Pd on activated carbon) at 23°C overnight. The reaction is filtered through celite, washed with H2O and the solvent is removed under reduced pressure. An aqueous solution of the residue is either directly filtered through a Whatman® Anotop inorganic membrane filter (Anotop 25 (0.2 μm) or Anotop 10 (0.02 μm)) or, if necessary, purified by Biogel P2 or Sephadex G10 column chromatography (H2O as eluent) and lyophilized to give the completely deprotected compound as a white solid.
GP B: A solution of the benzyl protected compound in EtOH/H2O (2:1) is hydrogenated at 1 atm in the presence of Pd(OH)2 C (Degussa type, 20% Pd(OH)2 on activated carbon) for several hours. The reaction is worked up as described above in GP A. Coupling procedures for the synthesis of compounds of group (d) wherein R2 is OH, Y' is CH and R2 is C(O)NHCHR4C(O)OH: A solution of 1.1 equivalents protected amino acid with a free amine, wherein, the protected amino acid is selected from the group consisting of Ala-OBn • pTSOH, Val-OBn • pTSOH, Leu-OBr • pTSOH, lle-OBn • pTSOH, Pro-OBn • pTSOH, Phe-OBn • pTSOH, Trp-OBn • pTSOH, Met-OBn • pTSOH, Ser-OBn • pTSOH, Thr- OBn • pTSOH, Cys-OBn • pTSOH, Tyr-OBn • pTSOH, Asn-OBn • pTSOH, Gln-OBn • pTSOH, Asp-(OBn)2 • pTSOH, Glu-(OBn)2 • pTSOH, Gly-OBn • pTSOH, Lys-OBn • pTSOH, Arg-OBn • pTSOH, and His-OBn • pTSOH (D- and L-amino acids; HCI salt may be used in lieu of the TSOH salt; other protecting groups in lieu of benzyl ether may be used), 1.1 equivalents HOBt, 1.0 equivalents of 108(3) and 1.1 equivalents of NMM in dry 0.15 M DMF is cooled to -20°C and 1.1 equivalents of EDC are added in one portion. The reaction mixture is stirred at -20°C for 1 hour and then allowed to reach 23°C slowly. After 16 to 36 h the reaction is taken up in ethyl acetate and extracted with 5% w/v citric acid solution (20 ml). The aqueous layer is further extracted with ethyl acetate (4 x 20 ml) and the combined organic layers are washed with sat. NaHCO3-sol. (40 ml) and brine (40 ml) followed by drying over MgSO4. After evaporation under reduced pressure the residual oil is purified by
SGCC (gradient elution with 30%→100% EtOAc in hexanes) to give the coupled protected mimetic.
Alternatively (same equivalents as above), the solution of the amino acid, HOBt, 108(3) and NMM in dry CH2CI2 is cooled to 0°C and EDC is added in one portion. The reaction mixture is stirred several h at 0°C and then allowed to reach 23°C slowly. After 4 to 18 h the reaction is worked up as described above.
Deprotection procedures for the above compounds: A solution of 1.1 equivalents of the benzyl protected mimetic (supra) in 80% aq. acetic acid is hydrogenated at 1 atm in the presence of a catalytic amount of Pd/C (10% Pd on activated carbon; approx. 0.5 equivalents) at 23°C overnight. The reaction is filtered through celite, washed with H2O and the solvent is removed under reduced pressure. An aqueous solution of the residue is either directly filtered through a Whatman® Anotop inorganic membrane filter (Anotop 25 (0.2 μm) or Anotop 10 (0.02 μm)) or, if necessary, purified by Biogel P2 or Sephadex G10 column chromatography (H2O as eluent) and lyophilized to give the completely deprotected compound as a white solid.
Alternatively, a solution of the benzyl protected compound (supra) in 0.10 M EtOH/H2O (2:1 ) is hydrogenated at 1 atm in the presence of Pd(OH)2/C (Degussa type, 20% Pd(OH)2 on activated carbon; catalytic amount approx. 0.5 equivalents) for several hours. The reaction is worked up as described above.
Coupling procedures for the synthesis of compounds of group (d) wherein R2 is OH, Y' is alkylene substituted with one or two OH and R2 is C(0)NHCHR C(O)OH: Starting from a solution of 1.1 equivalents protected amino acid with a free amine as mentioned above, 1.1 equivalents HOBt), 1.0 equivalents carboxylic acid derived from 113(3) and 1.1 equivalents NMM in dry 0.15 M DMF the coupled protected mimetics are prepared according to the procedure described above for the compounds of group (d) wherein R2 is OH, Y" is CH2 and R2" is C(O)NHCHR C(O)OH.
Deprotection procedures for the synthesis of the above compounds: The protected mimics above are deprotected as described above for the compounds of group (d) wherein R2 is OH, Y' is CH2 and R2' is C(O)NHCHR C(O)OH.
Reduction of the azides with P h3/H2O: A solution of the azide (1 mmol) and PPh3 (1.1 up to 2 mmol) in THF (0.2 M) and H2O (21 μl) is stirred at 23°C for 2 up to 7 days. The reaction mixture is concentrated in vacuo and residual oil is purified by SGCC (gradient elution with the CH2CI2:MeOH:NH OH solvent system) to give the desired amine.
Asymmetric dihydroxylation (AD-reaction): The diols are prepared from the unsaturated esters according to the literature protocol [Sharpless et al. J. Org. Chem. 57:2768-2771 (1992); Kolb et al. Chem. Rev. 94:2483-2547 (1994)] as follows: A solution of AD-mix (α or β) (1.4 g/mmol olefin) in tert.-butanol (5 ml) and H2O (5 ml) is cooled to 0°C, MeSO2NH2 and the olefin (1 mmol) are added and the heterogeneous mixture is stirred at 4°C until completion is indicated by tic (up to 48h, to avoid very slow conversion, addition of extra potassium osmate (1.3 mg) is recommended). Sodium sulfite (1.5g) is added at 4°C and stirring is continued at 23°C for 30min. Triple extraction with EtOAc is followed by washings with 1 N NaOH and brine. After drying over Na2SO4 and removal of the solvent in vacuo the residual slightly yellow solid is purified by SGCC (gradient elution EtOAc in hexanes) to give the desired diol.
Peptide coupling with EDC HOBt - Procedure A: A solution of the amine, HOBt, the carboxylic acid and NMM in dry DMF is cooled to -20°C and EDC is added in one portion. The reaction mixture is stirred at -20°C for 1h and then allowed to reach 23°C slowly. After 16 to 36 h the reaction is taken up in ethyl acetate and extracted with 5% w/v citric acid solution (20 ml). The aqueous layer is further extracted with ethyl acetate (4 x 20 ml) and the combined organic layers are washed with sat. NaHCO3-sol. (40 ml) and brine (40 ml) followed by drying over MgSO4. After evaporation under reduced pressure the residual oil is purified by SGCC (gradient elution with 30%→100% EtOAc in hexanes) to give the coupled compound.
Procedure B: A solution of the amine, HOBt, the carboxylic acid and NMM in dry CH2CI2 is cooled to 0°C and EDC is added in one portion. The reaction mixture is stirred several h at 0°C and then allowed to reach 23°C slowly. After 4 to 18h the reaction is worked up as described above in Procedure A.
Removal of the Boc protecting group: A solution of the Boc peptide in dry CHCI3 (1 ml) is treated with TFA (1 ml) at 0°C and stirred for 90 min. slowly reaching 23°C. The reaction mixture is evaporated under reduced pressure, twice CHCI3 (15 ml) is added and the solvent is removed in vacuo. The residual oil is taken up in MeOH (10 ml) and Dowex 1X8-50 OH resin is added until pH 8 is reached. The resin is filtered off, washed with MeOH, the solvent is removed in vacuo and the residue is used in the next step without further purification.
Introduction of the diacid moiety via activated esters: A solution of the amine in CHCI3 or a mixture of CHCI3 or CH2CI2 and DMF is cooled to 0°C and the succinimide ester [The
monobenzyl N-succinimidyl glutarate and the corresponding succinate are prepared according to the following protocol: i) glutaric or succinic anhydride, BnOH, CHCI3, pyridine, DMAP, 50°C; ii) HOSu, EDC, DCM. The latter step from: Spevak et al. J. Am. Chem. Soc. 115:1146-1147 (1993)] is added in one portion. If the TFA salt of the amine is employed the reaction mixture is treated with NMM until a basic pH is achieved. The reaction mixture is stirred at 0°C for several h and then allowed to reach 23°C slowly. After 16 to 36h the reaction is taken up in ethyl acetate and extracted with 5% w/v citric acid solution (20 ml). The aqueous layer is further extracted with ethyl acetate (4 x 20 ml) and the combined organic layers are washed with sat. NaHCO3-sol. (40 ml) and brine (40 ml) followed by drying over MgSO4 or Na2SO4 in the case of unprotected diols. After evaporation under reduced pressure the residual oil is purified by SGCC (gradient elution with 40%→100% EtOAc in hexanes) to give the coupled compound.
A Preparation of the starting compounds Example A1 : Preparation of compound (19)
(a) Svnthesis of 1.2-epoxy-3-(tri-O-benzyl-α-L-fucopyranosyl) propane (18): A solution of 3-(tri-O-benzyl-α-L-fucopyranosyl)-1-propene 17 [Uchiyama et al. Bioorg. Med. Chem. 4:1149-1165 (1996)] (7.0g, 15.3 mmol) in CH2CI2 (70 ml) is cooled to 0°C and mCPBA (8.5g, ca. 25 mmol, ca. 50% w/w) is added followed by stirring at 23°C for 11h. The reaction is quenched with icewater, taken up in ether and the excess mCPBA is destroyed with Na2SO3 in sat. NaHCO3-sol. The organic layer is extracted twice with sat. NaHCO3, treated with brine and dried over MgSO4. Removal of the solvent in vacuo left a yellow oil, which is purified by SGCC (gradient elution 20%→35% EtOAc in hexanes) to yield 18 as a colorless oil (1 :1 diastereomeric mixture).
(b) Svnthesis of 1-azido-3-(tri-O-benzyl-α-L-fucopyranosyl)-2-propanol (19): To a solution of 18 (5.90g, 12.4 mmol) in EtOH/H2O (9:1, 25 ml) is added NaN3 (4.04g, 62.2mmol) and NH4CI (3.32 g, 62.2mmol) and the resulting suspension is heated to reflux for 1.5h. After reaching 23°C, the reaction is taken up in ether, washed with H2O, brine and dried over MgSO4. Removal of the solvent in vacuo leaves a yellow oil, which is purified by SGCC (gradient elution 20%→33% EtOAc in hexanes) to yield 19 as a yellow oil (1 :1 diastereomeric mixture). Separation of the diastereomers is performed by HPLC on a semiprepara- tive column with hexane/2-propanol 99.5:0.5 at a flow rate of 9 ml/min.
Example A2: Preparation of compound (25)
(a) Svnthesis of 1-azido-2-(2-phenethoxy)-3-(tri-O-benzyl-α-L-fucopyranosyl)propane (20): A biphasic solution of 19b (207 mg, 400 μmol) in 2-bromoethylbenzene (3 ml) and 50 % aqueous NaOH-solution (2 ml) is stirred for 5 days at 23°C in the presence of n-Bu4NHSO4 (22 mg, 65 μmol). The reaction is diluted with Et2O, washed with H2O, 5 % citric acid, sat. NaHCO3-sol. and brine, followed by drying over MgSO4. The solvent is removed in vacuo and the remaining oil is purified by SGCC (0%→10%→20%→50% EtOAc in hexanes) to yield 20b as a yellow oil. The corresponding diastereomer 20a is obtained similarly by treatment of 19a (281 mg, 543μmol) in 2-bromoethylbenzene (4.1 ml) and 50 % aq. NaOH- sol. (2.7 ml) in the presence of n-Bu4NI (30 mg, 81 μmol) and n-Bu4NHSO4 (30mg, 88μmol) for 10 days at 23°C to afford 20a as a yellow oil.
(b) Svnthesis of 2-(2-phenethoxy)-2-(tri-O-benzyl-α-L-fucopyranosyl)-1 -propyl amine (23): A solution of 20a (29.1 mg, 46.8 μmol) in THF (0.5 ml) and H2O (1 drop) is treated with PPh3 (15mg, 57.2μmol) according to the general procedure for 2.5 days at 23°C to give amine 23a as a colorless oil. The corresponding diastereomer 23b is obtained similarly by treatment of 20b (46 mg, 74 μmol) in THF (0.5 ml) and H2O (1 drop) with PPh3 (24 mg,
91.5 μmol) for 1.25 days at 23°C to afford amine 23b as a colorless oil.
(c) Svnthesis of 1 -(O-benzyl-N-tert.-butoxycarbonyl-L-threonine)-2-(2-phenethoxy)-3-(tri-O- benzyl-α-L-fucopyranosyl)propane (24): A solution of 23a (24mg, 40.3μmol), EDC (9.4mg, 49.0μmol), HOBt (6.6mg, 48.8 μmol), N-Boc-O-benzyl-L-threonine (14.4mg, 46.5μmol) and NMM (10μl, 91 μmol) in dry DMF (0.7 ml) is coupled according to the general procedure (GP A) for 51 h to give 24a as a white solid. The corresponding diastereomer 24b is obtained similarly, by treatment of 23b (35.7 mg, 59.9μmol) with EDC (13.8 mg, 72.0 μmol), HOBt (9.8mg, 72.5μmol), N-Boc-O-benzyl-L-threonine (22.0 mg, 71.1 μmol) and NMM (15μl, 136μmol) in dry DMF (1.0ml) according to the general procedure for 21 h to give 24b as a white solid.
(d) Svnthesis of 1-(3-O-benzyl-2-monobenzyl-succinamidyl-L-threonine)-2-(2-phenethoxγ)- 3-(tri-O-benzyl-α-L-fucopyranosyl)propane (25): According to the general procedure Boc carbamate 24a (34.9 mg, 39μmol) is deprotected and coupled with monobenzylsuccinate (11.7mg, 56.2μmol), EDC (11.4mg, 59.5μmol), HOBt (8.6mg, 63.6μmol) and NMM (11μl, 100μmol) in dry DMF (0.9 ml) for 33h to give 25a (37.0mg, 98%) as a white solid. The
corresponding diastereomer 25b is obtained similarity by deprotection of Boc carbamate 24b (44.7mg, 50.4μmol) and subsequent coupling with monobenzylsuccinate (12.1mg, 58.1μmol), EDC (14.8mg, 77.2μmol), HOBt (9.1mg, 67.3μmol) and NMM (12μl, 129μmol) for 38h to afford 25b as a white solid.
Example A3: Preparation of compound (26)
(a) Svnthesis of 1-azido-2-(3-phenyl-2-propenoxy)-3-(tri-O-benzyl-α-L-fucopyranosyl)pro- pane (21 ): To a solution of 19 (400 mg, 773 μmol) in THF (5ml) and DMF (0.9 ml) is subsequently added NaH (95%) (56mg, 2.33 mmol) and cinnamyl bromide (309 mg, 1.57 mmol). The mixture is heated to 65°C for 1h, cooled to 23°C, diluted with Et2O, washed with H2O and brine, followed by drying over MgSO4 The solvent is removed in vacuo and the remaining oil is purified by SGCC (15%→18% EtOAc in hexanes) to yield 21 as a yellow oil (1 :1 diastereomeric mixture).
(b) Svnthesis of N-(tert.-butoxycarbonyl)-2-(3-phenylpropoxy)-3-(tri-O-benzyl-α-L- fucopyranosyl)-1 -propyl amine (26): A solution of 21 (343 mg, 541 μmol) and Boc2O (149mg, 683μmol) in EtOAc (6.1 ml) is stirred in the presence of Pd/C (16.5mg, 10% Pd on activated carbon) for 2 days at 23°C under atmospheric hydrogen pressure. The catalyst is filtered off through celite, washed with EtOAc, the solvent is removed in vacuo and the remaining oil is purified by SGCC (16%→18%→20%→33% EtOAc in hexanes achieves separation of the two diastereomers) to give Boc-carbamate 26 as a pale yellow oil.
Example A4: Preparation of compound (28b)
(a) Svnthesis o(2S)-1 -((2S.3ff)-4-benzyloxy-2-(tert-butoxycarbonylamino)-3-hvdroxybutyr- amidyl)-2-(3-phenylpropoxy)-3-(tri-O-benzyl-α-L-fucopyranosyl)-propane (27b): According to the general deprotection procedure Boc-carbamate 26b (128 mg, 180 μmol) is deprotected and subsequently coupled to (2S,3S)-4-benzyloxy-2-tert.-butoxycarbonylamino-2-hydroxy- butanoic acid 16a (70 mg, 215 μmol) by treatment with EDC (42 mg, 219 μmol), HOBt (30 mg, 222 μmol) and NMM (25 μl, 227 μmol) in DCM (2.0 ml) for 5.5 h to yield 27b as a yellow oil.
(b) Svnthesis of (2S)-1-((2S.3ff)-4-benzyloxy-2-(benzylsuccinamidyl-3-hydroxybutyramidyl)- 2-(3-phenylpropoxy)-3-(tri-O-benzyl-α-L-fucopyranosyl)-propane (28b): According to the general procedure Boc-carbamate 27b (103 mg, 112 μmol) is deprotected and subsequent-
ly coupled to monobenzyl succmate (26.6 mg, 128 μmol) by treatment with EDC (25 mg, 130 μmol), HOBt (18.2mg, 135 μmol) and NMM (26 μl, 236 μmol) in DCM (1.1 ml) for 4h to yield 26b as a yellow oil.
Example A5: Preparation of compound (32b)
(a) Svnthesis of 1 -azιdo-2-(tert.-butoxycarbonylrnethoxy)-3-(tri-O-benzyl-α-L-fucopyranosyl)- propane (22): A biphasic solution of 19a 19b (ca. 1.3) (706 mg, 1.36 mmol), tert.-butyl- bromoacetate (2.0 ml, 13.6 mmol), toluene (2.8 ml) and 50 % aqueous NaOH-solution
(2 ml) is stirred for 2 days at 4°C in the presence of n-Bu NHSO4 (46 mg, 136 μmol) The reaction is diluted with Et2O, washed with H2O, 5 % citric acid, sat. NaHCO3-sol. and brine, followed by drying over MgSO . The solvent is removed in vacuo and the remaining oil is purified by SGCC (20% EtOAc in hexanes) to yield 22 as a slightly yellow oil (diastereo- menc ratio 22a/22b ca. 1 :3).
(b) Synthesis of 1-amιno-2-(tert.-butoxycarbonylmethoxy)-3-(trι-O-benzyl-α-L-fucopyran- osvDprooane (29): Azide 22 (240 mg, 0.38 mmol) is treated with PPh3 (120 mg, 0.46 mmol) in THF (2.2 ml) and H2O (2 drops) for 3 days according to the general procedure to give 29 as a colorless oil (diastereomeπc ratio 29a 29b ca 1 :3)
(c) Svnthesis of 1 -(O-benzyl-N-tert -butoxycarbonyl-L-threonιne)-2-(tert.-butoxycarbonyl- methoxy)-3-(trι-O-benzyl-α-L-fucopyranosyl)propane (30) A solution of 29 (112.5 mg, 186 μmol), EDC (40.8 mg, 213 μmol), HOBt (29.4 mg, 218 μmol), N-Boc-O-benzyl-l-threonιne (64.2 mg, 207 μmol) and NMM (45 μl, 409 μmol) in dry DMF (3 0 ml) is coupled according to the general procedure for 51 h to give 30 as a colorless oil Separation by SGCC (30%→- 40%→50% EtOAc in hexanes) of the diastereomers affords 30b as a white solid.
(d) Synthesis of (2S)-1-(3-O-benzyl-2-monobenzyl-succιnamιdyl-L-threonιne)-2-(carboxyl- methoxy)-3-(tri-O-benzyl-α-L-fucopyranosyl)propane (31 b): According to the general deprotection procedures Boc carbamate and tert.-butyl ester 30b (87.5 mg, 97.5 μmol) are simultaneously deprotected (10.5h) and the resulting TFA-salt is treated with BnO2C(CH2)2CO2Su (40 mg, 131 μmol) and NMM (60 μl, 546 μmol) in dry DMF (2.2 ml) for 18h to give 31b as a colorless oil. In this case the workup procedure is changed to EtOAc as extracting solvent and consecutive washings with 1 HCI and brine, followed by drying over MgSO4 to assure isolation of the carboxylic acid, which is chromatographed on silica gel (DCM:MeOH:HOAc 29:1 :0.1 →19:1 :0.1).
(e) Svnthesis of (2S)-1-(3-O-benzyl-2-monobenzyl-succinamidyl-L-threonine)-2-(tetradecyl- aminocarbonylmethoxy)-3-(tri-O-benzyl-α-L-fucopyranosyl)propane (32b): According to the general coupling procedure B carboxylic acid 31 b (3.5 mg, 46.7 μmol) is coupled with tetra- decyl amine (11.1 mg, 52.0 μmol) using EDC (11.0 mg, 57.4 μmol) and NMM (11 μl, 102 μmol) in CHCI3 (0.7 ml) for 26h to give 32b as a yellow oil.
Example A6: Preparation of compound (34b)
(a) Svnthesis of (2S)-1-(3-O-benzyl-2-monobenzyl-succinamidyl-L-threonine)-2-(serinol- carbonylmethoxy)-3-(tri-O-benzyl-α-L-fucopyranosyl)propane (33b): According to the general procedure A carboxylic acid 31b (45.1 mg, 48.4 μmol) and serinol (5.8 mg, 63.7 μmol) are coupled using EDC (13.7 mg, 71.5 μmol), HOBt (9.3 mg, 68.8 μmol) and NMM (13 μl, 118 μmol) in dry DMF (1.0 ml) for 12h to give 33b as a colorless oil (SGCC with DCM/MeOH 9:1).
(b) Svnthesis of (2S)-1-(3-O-benzyl-2-monobenzyl-succinamidyl-L-threonine)-2-(dimyristoyl- serinolcarbonylmethoxy)-3-(tri-O-benzyl-α-L-fucopyranosyl)propane (34b): To a solution of diol 33b (30.1 mg, 30.0 μmol) and pyridine (60 μl, 742 μmol) in dry DCM (0.45 ml) is added freshly distilled myristoyl chloride (49 μl, 180 μmol) at 23°C and the mixture is stirred for 4.5h. After dilution with DCM, the organic layer is successively washed with 1 N HCI-sol., sat. NaHCO3-sol. and brine, followed by drying over MgSO4. Removal of the solvent in vacuo gives a yellow oil, which is purified by SGCC (66% EtOAc in hexanes) to afford 34b as a colorless oil.
Example A7: Preparation of compound (37)
(a) Svnthesis of N-tert.-butoxycarbonyl-N-(methoxycarbonylmethyl)-2-(tri-O-benzyl-α-L-fuco- pyranosvDethyl amine (36): A solution of 2-(tri-O-benzyl-α-L-fucopyranosyl)-acetaldehyde 35 (724mg, 1.57mmol), synthesized according to the procedure of Uchiyama et al [Bioorg. Med. Chem. 4:1 149 (1996)], glycine methyl ester hydrochloride (197.4 mg, 1.57 mmol), Et3N (0.44 ml, 3.14mmol) and MgSO4 (132.4 mg, 1.1 mmol) in dry CH2CI2 (3.3 ml) is stirred at 23°C for 13h. The solid remains are filtered off, washed with dry CH2CI2 and the solvent is removed in vacuo. The imine produced is dissolved in dry MeOH (9ml) and cooled to 0CC, whereas NaBH (150mg, 3.9 mmol) is added in one portion. After 20 min. the reaction mixture is concentrated under reduced pressure and the remaining oil is coevaporated with
CH2CI2 (25ml) to remove the rest MeOH. The residue is dissolved in CH2CI2 (15ml) and Boc2O (795mg, 3.6 mmol) is added at 0°C. The reaction is warmed up to 23°C and stirred for 50 min. After diluting with Et2O, the organic layer is washed with 5%w/v citric acid sol., sat. NaHCO3-sol. and brine, followed by drying over MgSO4. The solvent is removed in vacuo and the remaining oil is purified by SGCC (gradient elution 20%→30%→35%→40% EtOAc in hexanes) to give 36 as a colorless oil.
(b) Svnthesis of N-tert.-butoxycarbonyl-N-(carboxylmethyl)-2-(tri-O-benzyl-α-L-fucopyran- osvDethyl intermediate amine: A solution of methyl ester 36 (600mg, 0.95mmol) in THF (4.5ml) is treated with LiOH (19ml, 0.25m solution in MeOH/H2O 3:1 ) and stirred at 4°C for 42h. The solution is acidified with 1 N HCI-sol. until pH 1-2 is reached and extracted with EtOAc, washed with brine and dried over MgSO4. Removal of the solvent in vacuo affords the title acid as a colorless foam.
(c) Svnthesis of N-tert.-butoxycarbonyl-N-(tetradecylaminocarboxylmethyl)-2-(tri-O-benzyl- α-L-fucopyranosyl)ethyl amine intermediate: According to the general procedure the above acid (225 mg, 363 μmol) is coupled with tetradecyl amine (85 mg, 398 μmol) using EDC (76.5mg, 399μmol) and NMM (84μl, 764μmol) in CHCI3 (3.5ml) for 2.5 days to give the title amide as a slightly yellow oil.
(d) Svnthesis of N-(tetradecylaminocarboxylmethyl)-2-(tri-O-benzyl-α-L-fucopyranosyl)ethyl amine (37): According to the general deprotection procedure the above Boc carbamate (205mg, 252μmol) is deprotected to give 37 as a slightly yellow oil.
Example A8: Preparation of compound (16)
(a) Ethyl (E)-ω-benzyloxy-2-alkenoate (11): Prepared from the corresponding ω-benzyloxy- alkanal 10 according to Blanchette et al. [Tetrahedron Lett. 2183-2186 (1984)] as follows: To a suspension of LiCI (12 mmol) and triethyl phosphonoacetate (12 mmol) in dry CH3CN (100 ml) is added DBU (10 mmol) followed by the aldehyde 10 Bn-O- CHz^.rCHO (10 mmol) at 23°C and the reaction is stirred for ca. 4h. The mixture is taken up in ether, extracted with 1N HCI, sat. NaHCO3-sol. and brine, dried over MgSO4. After removal of the solvent in vacuo the residue is purified by SGCC (15% EtOAc in hexanes) to give the ethyl (E)-ω-benzyloxy-2-alkenoate 11 as a yellow oil. Ethyl (E)-4-benzyloxy-2-butenoate (11a); ethyl (£)-5-benzyloxy-2-pentenoate (11b); ethyl (E)-6-benzyloxy-2-hexenoate (11 c).
(b) Synthesis of ethyl ω-benzyloxy-cis-2.3-dihvdroxyalkanoate (12): Prepared from the unsaturated ester according to the general procedure to give 12 as a colorless solid. Ethyl (2f*?,3fl)-4-benzyloxy-2,3-dihydroxybutanoate (12a); ethyl (2R,3S)-5-benzyloxy-2,3-di- hydroxypentanoate (12b); ethyl (2f?,3S)-6-benzyloxy-2,3-dihydroxyhexanoate (12c).
(c Ethyl ω-benzyloxy-cis-3-hvdroxy-2-(4-nitrobenzenesulfonyloxy)alkanoate (13): Prepared from diol 12 according to Sharpless et al. [J. Org. Chem. 56:2869-2875 (1991 )] as follows: A solution of diol 12 (5 mmol) in dry pyridine (17 ml) is cooled to 0°C and 4-nitrobenzene- sulfonyl chloride (5.05 mmol, freshly recrystallized from hexane) is added. After standing for 24-30h at 4°C the mixture is poured into ice and extracted with ether. After multiple washings with sat. CuSO4-sol., one washing with brine and drying over MgSO4, the solvent is removed in vacuo. The residual oil is purified by SGCC (30%→40% EtOAc in hexanes) to give the 2-nosylate 13 as a yellow oil. Ethyl (2/?,3 *?)-4-benzyloxy-3-hydroxy-2-(4-nitrobenz- ene-sulfonyloxy)-butanoate (13a); ethyl (2/*?,3S)-5-benzyloxy-3-hydroxy-2-(4-nitrobenzene- sulfonyloxy)pentanoate (13b).
(d) Ethyl trans-2-azido-ω-benzyloxy-3-hvdroxyalkanoate (14): Prepared from nosylate 3 according to Sharpless et al. [J. Org. Chem. 56: 2869 (1991)] as follows: A solution of nosylate 13 (5 mmol) and sodium azide (30 mmol) in dry DMF (50 ml) is stirred at 50CC for 14 h. The reaction mixture is poured into ice water and extracted three times with ether. The combined organic layers are washed with brine and dried over MgSO4. After removal of the solvent in vacuo the residue is purified by SGCC (30%→40% EtOAc in hexanes) to give azide 14 as a slightly yellow oil. Ethyl (2S,3f?)-2-azido-4-benzyloxy-3-hydroxybutanoate (14a), ethyl (2S,3fl)-2-azido-5-benzyloxy-3-hydroxybutanoate (14b).
(e) Svnthesis of ethyl trans-(o-benzyloxy-2-tert.-butoxycarbonylamino-3-hvdroxyalkanoate (15): A solution of azide 14 (1 mmol) and Boc2O (1.2 mmol) in EtOAc (15 ml) is hydrogenated in the presence of Rh/C (30 mg, 5% Rh on activated carbon) at atmospheric pressure under vigorous stirring for 7 h at 23°C. The reaction mixture is filtered through a celite pad and washed with EtOAc. The solvent is removed in vacuo and the residue is purified by SGCC (30% EtOAc in hexanes) to give 15 as a colorless oil. Ethyl (2S,3fl)-4-benzyloxy-2- tert.-butoxycarbonylamino-3-hydroxybutanoate (15a); ethyl (2S,3S)-5-benzyioxy-2-tert.- butoxycarbonylamino-2-hydroxypentanoate (15b).
(f) Svnthesis of trans-ω-benzyloxy-2-tert.-butoxycarbonylamino-3-hvdroxyalkanoic acid (16): An ice-cold solution of LiOH (20 ml, 0.25 M in MeOH/H2O 3:1 ) is added to ethyl ester 15 (1 mmol) at 0°C and vigorous stirring is continued for 2 days at 4°C. The reaction mixture is
acidified with cold 1 N HCI to pH 1 -2 and quickly extracted with EtOAc, washed with brine and dried over MgSO . The solvent is removed in vacuo to give acid (16) as a slightly yellow oil. (2S,3S)-4-Benzyloxy-2-tert.-butoxycarbonylamino-2-hydroxybutanoic acid (16a); (2S,3S)-5-benzyloxy-2-tert.-butoxycarbonylamino-2-hydroxypentanoic acid (16b).
Example A9: Preparation of compound 39
(a) Svnthesis of 1-((2S.3fl)-4-benzyloxy-2-(tert-butoxycarbonylaminio)-3-hvdroxybutyramid- yl)-N-(tetradecylaminocarbonylmethyl)-2-(tri-O-benzyl-α-L-fucopyranosyl)-ethane 38: According to the general procedure A amine 37 (103mg, 140μmol) is coupled to 16a (53mg, 163μmol) by treatment with EDC (32mg, 167μmol), HOBt (29mg, 215μmol) and NMM (35μl, 318μmol) in DMF 81.3ml) for 40h to yield 38 as a yellow oil.
(b) Svnthesis of 1-f(2S.3fD-2-benzylαlutaramidyl-4-benzyloxy-3-hvdroxybutyramidyl)-N- (tetradecylaminocarbonylmethyl)-2-(tri-O-benzyl-α-L-fucopyranosyl)-ethane 39: According to the general deprotection procedures Boc-carbamate 38 (88mg, 86μmol) is deprotected and subsequently coupled with monobenzyl N-succinimidyl giutarate (34mg, 106μmol) in DCM (1.5ml) in the presence of NMM (6μl) for 8h to obtain 39 as a yellow oil.
Example A9': Preparation of compound (47)
(a) Svnthesis of ethyl (E)-4-(tri-O-benzyl-α-L-fucopyranosyl)-2-butenoate (40): Prepared from the 2-(tri-O-benzyl-α-L-fucopyranosyl)-acetaldehyde 35 (synthesized according to the procedure of Uchiyama et al [Bioorg. Med. Chem. 4:1149 (1996)] according to Blanchette et al. [Tetrahedron Lett. 2183 (1984)] as follows: To a suspension of LiCI (215mg, 5.07mmol) and triethyl phosphonoacetate (1.00ml, 5.04mmol) in dry CH3CN (42ml) is added DBU (0.63 ml, 4.21 mmol) followed by the aldehyde 35 (1.94g, 4.21 mmol) at 23°C and the reaction is stirred for 6h. The mixture is taken up in ether, extracted with 1 HCI, sat. NaHCO3-sol. and brine, dried over MgSO4. After removal of the solvent in vacuo the residue is purified by SGCC (20%→22% EtOAc in hexanes) to give the α,β-unsatu rated ester 40 as a yellow oil.
(b) Svnthesis of ethyl (2 3S)-2.3-dihvdroxy-4-(tri-O-benzyl-α-L-fucopyranosyl)-butenoate (41): Prepared from the α,β-unsaturated ester 40 (2.09g, 3.94mmol) according to the general asymmetric dihydroxylation procedure to give 41 as a colorless oil.
(c) Svnthesis of ethyl (2ff. 3S)-3-hvdroxy-2-(4-nitrobenzenesulfonyloxy)-4-(tri-O-benzyl-α-L- fucopyranosvD-butanoate (42): Prepared from diol 41 according to Sharpless et al. [J. Org.
Chem. 56:2869 (1991)] as follows: A solution of diol 41 (1.925g, 3.41 mmol) in dry pyridine (11.4ml) is cooled to 0°C and 4-nitrobenzenesultonyl chloride (773mg, 3.49mmol, freshly recrystallized from hexane) is added. After standing for 25h at 4°C the mixture is poured into ice and extracted with ether. After multiple washings with sat. CuSO4-sol., one washing with brine and drying over MgSO4l the solvent is removed in vacuo. The residual oil is purified by SGCC (30%→40%→50%→60% EtOAc in hexanes) to give the 2-nosylate 42 as a pale yellow foam.
(d) Svnthesis of ethyl (2S.35)-2-azido-3-hvdroxy-4-(tri-O-benzyl-α-L-fucopyranosyl)-butan- oate (43): Prepared from nosylate 42 according to Sharpless et al [J. Org. Chem. 56:2869 (1991)] as follows: A solution of nosylate 42 (1.97g, 2.63 mmol) and sodium azide (1.02g, 15.7mmol) in dry DMF (26ml) is stirred at 50°C for 21 h. The reaction mixture is poured into ice water and extracted three times with ether. The combined organic layers are washed with brine and dried over MgSO4. After removal of the solvent in vacuo the residue is purified by SGCC (30%→35% EtOAc in hexanes) to give 43 as a slightly yellow oil.
(e) Svnthesis of ethyl (2S.3S)-2-azido-3-(3-phenyl-2-propenoxy)-4-(tri-O-benzyl-α-L-fuco- pyranosyD-butanoate (44): Prepared from nosylate 42 according to Lakhmiri et al. Tetrahedron Lett. 30:4669-4672 (1989)] as follows: To a clear solution of tris(dibenzylideneace- tone)-dipalladium(O) (dba3Pd2) (23mg, 25μmol) and dppb (43mg, 0.1 mmol) is added a solution of 43 (590mg, 1.Ommol) and cinnamyl ethyl carbonate (Cinnamyl ethyl carbonate is prepared as follows: To a solution of cinnamyl alcohol (1.00g, 7.45mmol) and pyridine (3ml, 37.1mmol) in DCM (12ml) is added ethyl chloroformate (1.07ml, 11.2mmol) at 0°C and the mixture is stirred while warming up to 23°C for 90 min. The reaction is taken up in ether, extracted with icβwater, sat. CuS04-sol. (3x), brine and dried over MgS04. After removal of the solvent in vacuo the residual oil is purified by SGCC (hexanes: ether 4: 1) to give the cinnamyl ethyl carbonate (1.47g, 96%) as a colorless oil) (627mg, 3.0 mmol) in dry THF (26ml) at 23°C and the reaction is stirred at 65°C for 3h. The reaction mixture is concentrated in vacuo and the residue is purified by SGCC (15%→16%→20% EtOAc in hexanes) to give 44 as a yellow oil.
(f) Svnthesis of ethyl (2S.3S)-2-(tert.-butoxycarbonylamino)-3-(3-phenylpropoxy)-4-(tri-O- benzyl-α-L-f ucopyranosvD-butanoate (45) : A solution of azide 44 (260mg, 368μmol) and Boc2O (100mg, 458μmol) in EtOAc (4.8ml) is stirred in the presence of Pd/C (11mg, 10% Pd on activated carbon) for 38h at 23°C under atmospheric hydrogen pressure. The catalyst is filtered off through celite, washed with EtOAc, the solvent is removed in vacuo and
the remaining oil is purified by SGCC (20% EtOAc in hexanes) to give 45 as a pale yellow oil.
(α) Svnthesis of Compound 46: (step i) A solution of methyl ester 45 (600mg, 0.95mmol) in
THF (4.5ml) is treated with LiOH (19ml, 0.25M solution in MeOH/H2O 3:1) and stirred at 4°C for 42 h. The solution is acidified with 1 N HCI-sol. until pH 1-2 is reached and extracted with EtOAc, washed with brine and dried over MgSO . Removal of the solvent in vacuo affords the title acid, (step ii) According to the general procedure the above acid (225mg,
363μmol) is then coupled with tetradecyl amine (85mg, 398μmol) using EDC (76.5mg,
399μmol) and NMM (84μl, 764μmol) in CHCI3 (3.5ml) for 2.5 days to give 46.
(h) Svnthesis of Compound 47: (step i) According to the general deprotection procedure the above Boc carbamate 46 (205mg, 252μmol) is deprotected to give the intermediate amine
(181mg, 99%) as a slightly yellow oil.
(step ii) According to the general procedure A amine from step i (103mg, 140μmol) is coupled to 16a (53mg, 163μmol) by treatment with EDC (32mg, 167μmol), HOBt (29mg,
215μmol) and NMM (35μl, 318μmol) in DMF (1.3ml) for 40h to yield the Boc-carbamate intermediate (89mg, 62%) as a yellow oil.
(steps iii-iv) According to the general deprotection procedures Boc-carbamate (88mg,
86μmol) is deprotected and subsequently coupled with monobenzyl n-succinimidyl glutarate
(34mg, 106μmol) in DCM (1.5ml) in the presence of NMM (6μl) for 8h to obtain 47 as a yellow oil.
Example A10: Preparation of compound (54)
(a) Fmoc deprotection of compound 48: A solution of compound 48
[Wong et al. J. Am. Chem. Soc. 118:6826 (1996)] (411mg, O.δmmole) in 40% HNEt2 THF (10ml) is allowed to proceed at RT for 2h and is then evaporated in vacuo. The residue is
purified by flash column chromatography eluting with CHCI3: MeOH (19:1) then (9:1) to afford 48*.
(b) Coupling of 49 to fucosyl amine to form 50: A mixture of 48' (292 mg, 0.5 mmole), 49
(218 mg, O.δmmole) [Wong et al. Tetrahedron Lett. 36:4081 (1995)] and CH2CI2 (6ml) is cooled to 0°C. The coupling reagent HOBT (89mg, 0.6 mmole) is added followed by EDC (127mg, O.βmmole), and the solution is stirred at 0°C for 30 min. After being stirred at RT for 10h, the solvent is evaporated and the residue is diluted with EtOAc. The resulting organic layer is washed with H2O (2x10ml), 1 N HCI (2x5ml), saturated aqueous NaHCO3 (2x5ml), and saturated aqueous NaCl. The organic phase is dried over MgSO4, filtered, and concentrated. The residue is purified by flash column chromatography eluting with CHCI3: MeOH (19:1 ) to afford 50 (395mg, 79%).
(c) Svnthesis of 51 : To a solution of 50 (386mg, 0.4mmole) in 40ml of THF/DMF (1.1) is added tetrakis(triphenylphosphine)palladium(0) (45mg,0.04mrnole) and morpholine (0.34ml, 4.0mmole). After stirred at RT for 11h, the solvent is evaporated and the residue is taken up in 50ml of EtOAc. The resulting solution is washed three times with 30ml of 1 N HCI, dried over MgSO4, and concentrated in vacuo. The crude is purified by flash column chromatography eluting with CHCI3: MeOH (9:1 ) to afford 51.
(d) Svnthesis of 53: A mixture of H2N[(CH2)2O]3(CH2)2N3 52 (0.5 mmole; Toronto Research Chemicals Inc.), 51 (0.5 mmole) [Wong et al. Tetrahedron Lett 36:4081 (1995)] and CH2CI2 (.068 M) is cooled to 0°C. The coupling reagent HOBT (0.6 mmole) is added followed by EDC (0.6 mmole), and the solution is stirred at 0°C for 30min. After being stirred at RT for 10h, the solvent is evaporated and the residue is diluted with EtOAc. The resulting organic layer is washed with H2O (2x10ml, scaled accordingly, based on a 200-300mg scale for either substrate), 1 N HCI (2x5 ml), saturated aqueous NaHCO3 (2x5 ml), and saturated aqueous NaCl. The organic phase is dried over MgSO , filtered, and concentrated. The residue is purified by flash column chromatography eluting with CHCI3: MeOH (19:1) to afford 53.
(e) Preparation of 54: 53 (256mg, 0.2 mmole) is dissolved in ethanol: H2O: dioxane: AcOH (2:1 :2:1 , 2ml), and then a catalytic amount of Pd(OH)2 (Degussa type; Aldrich) on carbon is
added. Hydrogen is supplied to the reaction system through a ballon. After 6h the mixture is filtered through celite and concentrated in vacuo. The crude product is purified by biogel P2 (water). The collected fractions are combined and freeze dried to afford 54.
Example A11 : Preparation of 57
Compound 55 £} (1g, 2.7mmole; Avanti Polar Lipids, Inc.), HOSu (0.5g, 4.3mmole)
and EDC (0.6g, 3.1 mmole) are stirred in 65 ml of CH2CI2 at RT while shielded from light. After 6 h, the solution is washed with water, 1% HCI, saturated aqueous NaHCO3 and saturated aqueous NaCl. The organic phase is then dried with MgSO4, filtered, and concentrated under reduced pressure to yield 57 as a slightly yellow solid.
Example A12: Preparation of D-mannose C-glycoside aldehyde 5(14)
(a) To a solution of methyl α-D-mannopyranoside (1.96 g, 9.61 mmol), BnBr (8 ml, 67.3 mmol), and TBAI (177 mg, 048 mol) in THF (20 ml) at 0°C is added NaH (2.35 g, 57.6 mmol). The cooling bath is removed and the reaction mixture is allowed to stir for 24 h. The reaction is diluted with EtOAc (50 ml). The aqueous phase is extracted with EtOAc (2x30ml) and the combined organic phases are dried (MgSO4) and concentrated under reduced pressure providing the crude oil. Purification by silica gel flash chromatography (hexan:EtOAc, 100% to 9:1 to1 :1) gives α-methyl-2,3,4,6-O-tetra-benzyl-mannopyranoside 2(14).
(b) To a solution of 2(14) (1.0g, 2.56 mmol), at 0°C is added allyltπmethylsilane (1.22ml, 7.69mmol) followed by BF3 • Et2O (1.5ml, 12.8mmol). The reaction mixture is allowed to warm to 23°C and TMSOTf (100ml) is added and the solution is stirred for 24h. The mixture is poured into a saturated NaHCO3 solution (50ml) and the organic phase is diluted with CH2CI2 (50 ml). The aqueous phase is extracted with CH2CI2 (2x25ml) and the combined organic phases are dried (MgSO4), filtered, and concentrated under reduced pressure. The crude oil is purified by silica gel flash chromatography (CH2CI2/MeOH, 9:1) giving tetra- benzyl C-allylmannose 3(14) as a single α-anomer.
(c) To a solution of 3(14) (679mg, 1.20mmol) in CH2CI2 eOH (8ml:4ml) at -78°C is bubbled O3 in O2 until a blue color persists. To remove residual O3, pure O2 is bubbled through until the solution turns clear. DMS (1.7ml, 24.0 mmol) is added and the reaction mixture is warmed to 23°C and stirred for 24h. The reaction mixture is evaporated and partitioned bet-
ween a saturated NaHCO3 solution (50ml) and EtOAc (5ml). The aqueous phase is extracted with EtOAc (2x30ml) and the combined organic phases are dried and concentrated under reduced pressure. The crude oil is purified by silica gel flash chromatography (CH2CI2/MeOH) giving perbenzyl aldehyde 4(14).
(d) 2 mol (1132mg) of 4(14) is dissolved in a mixture of THF and water (3:1) and hydrogenated at 1 atm in the presence of a catalytic amount of Pd/C (Aldrich; 10% Pd/C). The mixture is allowed to react overnight and the catalyst is filtered off using a celite pad. The solvent is evaporated under vacuum and 5(14) is isolated as a mixture of aldehyde and dihydrate.
Example A13: Preparation of D-glucose C-glycoside aldehyde 12 (14)
Starting with methyl α-D-glucopyranoside (1.96g, 9.61 mmol) compound 12(14) is prepared in analogy with Example A12.
Example A14: Preparation of compound 21(14)
(a) 5 mmol of 2(14) is dissolved in dry acetonitrile (5 ml, 1.0) and 2 equivalents of allyl tri- methyl siiane are added followed by 0.5 eq of TMSOTf under argon. The mixture is allowed to react for 48h and acetic anhydride (2 eq) is added. After 10 min, the reaction is subjected to extractive work-up (ether/water) and purified by chromatography to yield 3.25 mmol (65%) of acetylated product. Deprotection is carried out by treatment with NaOMe in MeOH for 30 min and filtration through Dowex-H* affords 3-(α-2,3,4-O-tribenzylmannopyranosyl)-1- propene 15(14).
(b) 15(14) is subjected to a standard Mitsunobu reaction [Mitsunobu et al. Synthesis 1 (1981)] using PPh3 and diethyl azodicarboxylate with diphenyl phosphoryl azide as nucleo- phile. Purification by flash chromatography yields 3-(α-6-azide-2,3,4,tri-O-benzylmanno- pyranosyl)-1-propenal 19(14).
(c) 19(14) is treated with 1.5 eq of PPh3 in THF as solvent and in the presence of 1.5 eq of water for 3 h at RT. Purification is carried out by flash chromatography and the resulting amine is coupled with succinic anhydride (1.1 eq) and triethyl amine (1.1 eq) in MeOH [Uchiyama et al. Bioorg. & Med. Chem., 4: 1149 (1996)] to yield 20(14).
(d) 20(14) is exposed to EDT/HOBt mediated coupling (conditions vida supra) of the acid selected from the group consisting of acetic acid, phenylacetic acid and decanoic acid which is then subjected to ozonolysis in DCM/MeOH (5:1), quenched by DMS and extracted
from ether. Hydrogenation of the benzyl groups is carried out in THF:H2O mixture under 50 psi of H2 to yield 21(14).
Example A15: Preparation of Compound 22(14)
20(14) is treated with 1.1 eq of succinic anhydride in pyridine as solvent and in the presence of a catalytic amount of DMAP; conditions and workup are as above. The product so obtained is subjected to ozonolysis in DCM/MeOH (5:1), quenched by DMS and extracted from ether. Hydrogenation of the benzyl groups is carried out in THF:H2O mixture under 50 psi of H2 to yield 22(14).
Example A16: Preparation of 3-(α-6-sulphate-mannopyranosyl)-1-propenal 17(14) Treatment of 15(14) with 1.2 eq of sulfur trioxide pyridine complex in DMF as solvent according to Turvey et al. [Adv. Carb. Chem. Biochem. 20:183 (1965)]. The sulfated sugar is then subjected to ozonolysis in MeOH and quenched with DMS. Hydrogenation of the benzyl groups is carried out in THF:H2O mixture under 50 psi of H2 using standard conditions and workup as described supra to yield 17(14).
Example A17: Preparation of diacid derivative 18(14)
15(14) is treated with 1.1 eq of succinic anhydride in pyridine as solvent and in the presence of a catalytic amount of DMAP. The product so obtained is coupled with dibenzylglutamic acid using EDC/HOBt coupling system (conditions vida supra). Extractive workup (ether/water) gives the protected precursor, that is subjected to ozonolysis in DCM/MeOH (5:1 ) quenched by DMS and extracted from ether (conditions vida supra). Hydrogenation of the benzyl groups is carried out in THF:H2O mixture under 50 psi of H2 to yield 18(14) using standard conditions and workup as described supra.
Example A18: Preparation of L-fucose C-glycoside template
Starting from methyl α-L-fucopyranoside the L-fucose C-glycoside template is prepared according to Example A12.
Example A 19: Preparation of D-mannose O-glycoside 26(14)
(a) The O-allyl, O-propenyl, O-butenyl, and O-pentenyl α-(D)-glucoside 23(14) is prepared according to Fraser-Reid et al [Syntlett 927 (1992)] wherein the O-methyl α-(D)-mannoside
is stirred in neat solvent (e.g. 1.0 propenol (for the O-propenyl derivative), 1.0 allyl alcohol (for the O-allyl derivative), 1.0 butenol (for the O-butenyl derivative) or 1.0 O-pentenol (for the O-pentenyl derivative) at 90°C for 12 h. The product is then worked up and purified employing standard conditions vida supra.
(b) 700mg (2.8 mmol) of the O-allyl, O-propenyl, O-butenyl, or O-pentenyl α-(D)-mannoside 23(14) and 420 mg (6.2 mmol) of imidazole are dissolved in 3 ml anhydrous DMF and cooled down to 0°C. The solution is treated dropwise (15 min) with 810 μl (3.1 mmol) of TBDPSCl and the ice bath is removed. After stirring at RT for 2 h the reaction is quenched by addition of EtOAc and brine. The aqueous layer is extracted (2x) with EtOAc and the combined organic layers are dried over Na2SO , and concentrated. The crude mixture is chromatographed (70 g silica gel, Hex/EtOAc 1:1) to afford a slightly yellow oil.
950mg (1.94 mmol) of the triol are dissolved in 4ml of anhydrous THF and 36 mg (0.097 mmol) of TBAI and 1.15 ml (9.7 mmol) of BnBr are added. To the ice cooled solution 330mg (95%, 7.8 mmol) of NaH are added at once and the mixture is stirred overnight and allowed to warm up to RT. Under ice cooling the heterogeneous mixture is quenched with sat. NH4CI and after diluting with brine the mixture is extracted with ethyl ether (2x, 100ml). The combined organic layers are dried with MgSO4 and concentrated in vacuo. The crude mixture is chromatographed (100 g silica gel, Hex/Et2O 10:1) to give a slightly yellow oil.
(c) To a solution of the above prepared terminal olefin (679 mg, 1.20 mmol) in CH2CI2 MeOH (8 ml:4ml) at -78°C is bubbled O3 in O2 until a blue color persists. To remove residual O3, pure O2 is bubbled through until the solution turns clear. DMS (1.7 ml, 24.0 mmol) is added and the reaction mixture is warmed to 23°C and stirred for 24 h. The reaction mixture is evaporated and partitioned between a saturated NaHCO3 solution (50 ml) and EtOAc (5 ml). The aqueous phase is extracted with EtOAc (2x30ml) and the combined organic phases are dried and concentrated under reduced pressure. The crude oil is purified by silica gel flash chromatography (CH2CI2:MeOH) giving the perbenzyl aldehyde. The tert- butyldiphenylsilyl moiety is then removed by adding 1.0 M solvent THF to the perbenzyl aldehyde followed by the addition of TBAF (1.0 equivalents; 1.0 M solution). The reaction mixture is stirred for 2 h at 0°C. The reaction mixture is evaporated and partitioned between a saturated NaHCO3 solution (50ml) and EtOAc (5ml). The aqueous phase is extracted with EtOAc (2x30ml) and the combined organic phases are dried and concentrated under reduced pressure. The crude oil is purified by silica gel flash chromatography (CH2CI2:MeOH) giving the perbenzylated aldehyde 25(14).
(d) 2 mmol (1132 mg) of compound 25(14) is dissolved in a mixture of THF and water (3:1) and hydrogenated at 1 atm in the presence of a catalytic amount of Pd/C. The mixture is allowed to react overnight and the catalyst is filtered off using a celite pad. The solvent is evaporated under vacuum and the product 26(14) is obtained.
Example A20: Preparation of compound 28(14)
(a) The tertbutyldiphenylsilyl moiety of 24(14)
is removed by adding 1.0 solvent THF to the perbenzyl aldehyde followed by the addition of TBAF (1.0 equivalents; 1.0 M solution). The reaction mixture is stirred for 2 h at 0°C. The reaction mixture is evaporated and partitioned between a saturated NaHCO
3 solution (50ml) and EtOAc (5 ml). The aqueous phase is extracted with EtOAc (2x 30ml) and the combined organic phases are dried and concentrated under reduced pressure. The crude oil is purified by silica gel flash chromatography (CH
2CI
2 / MeOH) to provide the free alcohol. The free alcohol is dissolved in 4 ml of anhydrous methylene chloride and 1.1 equivalents of R'- bromide (chloride or iodide is also acceptable) is added wherein R' is selected from the group consisting of OH, H, N
3, OSO
3 2", OCOCH
2CH
2CONHCH(CH
2CO
2H)CO
2H, NHR' (R' = alkyl, acyl, decanoyl, phenylacetyl, COCH
2CH
2H) followed by 1.1 equivalents of NaH and the mixture is stirred overnight and allowed to warm up to RT. Under ice cooling the heterogeneous mixture is quenched with sat. NH
4CI and after diluting with brine the mixture is extracted with ethyl ether (2x, 100ml). The combined organic layers are dried with MgSO
4 and concentrated in vacuo. The crude mixture is chromatographed by silica gel flash chromatography (CH
2CI
2 / MeOH) to provide the protected olefin 27(14). (b) To a solution of 27(14) (679 mg, 1.20 mmol) in CH
2CI
2:MeOH (8ml:4ml) at -78°C is bubbled O
3 in O
2 until a blue color persists. To remove residual O
3, pure O
2 is bubbled through until the solution turns clear. DMS (1.7 ml, 24.0 mmol) is added and the reaction mixture is warmed to 23°C and stirred for 24 h. The reaction mixture is evaporated and partitioned between a saturated NaHCO
3 solution (50ml) and EtOAc (5ml). The aqueous phase is extracted with EtOAc (2x30ml) and the combined organic phases are dried and concentrated under reduced pressure. The crude oil is purified by silica gel flash chromatography
(CH
2CI
2/MeOH) giving the perbenzyl aldehyde. 2 mmol (1132mg) of the perbenzyl aldehyde is dissolved in a mixture of THF and water (3:1) and hydrogenated at 1 atm in the presence of a catalytic amount of Pd/C. The mixture is allowed to react overnight and the catalyst is filtered off using a celite pad. The solvent is evaporated under vacuum to afford 28(14).
Example A21 : Preparation of D-glucose O-glycoside template
The synthesis of the D-glucose O-glycoside template is achieved in exactly the same steps as that of D-mannose outlined in Example A19 or A20.
Example A22: Preparation of L-fucose O-glycoside template
10 mmol of L-fucose are placed in a roundbottom flask together with a large excess of allyl alcohol and heated to 90°C. Then 1 eq of boron trifluoride etherate is added dropwise and the mixture is allowed to react overnight. Next, the bulk of allyl alcohol is removed by evaporation in vacuo and the residue is passed through a silica gel column using ethyl acetate :- hexane as eluent, first 1 :4 to elute the remaining allyl alcohol and then 1 :1 to elute the fucose glycoside off the column mainly as α anomer.
To a solution of the above prepared terminal olefin (679mg, 1.20 mmol) in CH2CI2:MeOH (8ml:4ml) at -78°C is bubbled O3 in O2 until a blue color persists. To remove residual O3, pure O2 is bubbled through until the solution turns clear. DMS (1.7ml,24. Ommol) is added and the reaction mixture is warmed to 23°C and stirred for 24h. The reaction mixture is evaporated and partitioned between a saturated NaHCO3 solution (50ml) and EtOAc (5 ml). The aqueous phase is extracted with EtOAc (2 x 30ml) and the combined organic phases are dried and concentrated under reduced pressure. The crude oil is purified by silica gel flash chromatography (CH2CI2 / MeOH) giving the L-fucose O-glycoside template.
Example A23: Preparation of compound 18(15)
(a) Svnthesis of Compound 14(15): To a solution of methyl β-D-galactopyranoside (10 g, 51.5 mmol) in CH3CN (250 ml) is added benzaldehyde dimethyl acetal (15.6 ml, 103 mmol) followed by CSA (1.19 g, 5.15 mmol). After 30 min ET3N (1 ml) is added and the solvent is removed under reduced pressure and the crude solid is recrystallized from hot MeOH affording 14(15).
(b) Svnthesis of Compound 3-allyl-4.6-benzylidene-2-hvdroxy β-D-methylαalactopyranoside 15(15): To a solution of 14(15) (4.7 g, 16.7 mmol) in toluene (55 ml) is added BU2SnO (4.56
g, 18.3 mmol) and the solution is dehydrated using a Dean-Stark trap (130°C, 2 h). The reaction mixture is cooled to 70°C and TBAI (4.3 g, 11.7 mmol) is added followed by allylbromide (2.18 ml, 25 mmol). The solution is stirred at 130°C for 24 h before being cooled to 23°C and partitioned between EtOAc (200 ml) and saturated NaHCO3 (200 ml). The aqueous layer is extracted with EtOAc (2 x vol) and the combined organic layers are dried (MgSO4), concentrated under reduced pressure, and chromatographed (1:1 to 100% EtOAc/Hexane) giving 15(15).
(c) Svnthesis of Compound 16(15): To a solution of (COCI)2 (209 ml, 2.40 mmol) in CH2CI2 (4 ml) at -78°C is added DMSO (341 ml, 78.1 mmol). The reaction mixture is warmed to 0°C for 5 min and the re-cooled to -78°C. 15(15) (704 mg, 2.19 mmol) is dissolved in CH2CI2 (4 ml) and added slowly drop-wise. The reaction mixture is stirred for 30 min and DIPEA is added (1.48ml, 10.9 mmol). The reaction mixture is warmed to 23°C, diluted with CH2CI2 (100 ml), washed with saturated NaHCO3 (50 ml), and dried (MgSO4). The crude product is used directly in the next step without further purification.
To a solution of the above ketone in MeOH (20 ml) is added NH4OAc until the solution is saturated. Sodium cyanoborohydride (116 mg, 2.19 mmol) is added and the reaction mixture is stirred for 48 h. The reaction mixture is partitioned between EtOAc (100 ml) and saturated NaHCO3 (50 ml) and the aqueous layer is further extracted with EtOAc (2 x 50 ml). The combined organic layers are dried (MgSO4), concentrated under reduced pressure, and chromatographed (5% MeOH/ CH2CI2) giving 16(15).
(d) Svnthesis of Compound 17(15): To a solution of 8(15)
(806 mg, 1.38 mmol) in methylene chloride (5 ml) at 0°C is added DIPEA (510 ml, 2.86 mmol) followed by (COCI)2 (120 ml, 1.38 ml). The solution is stirred for 15 min at 0°C before 16(15) (296 mg, 0.92 mmol) is added as a solution in methylene chloride (1 ml). The reaction mixture is gradually warmed to 23°C and stirred for 24 h. The reaction mixture is diluted with CH2CI2 (50 ml) washed with a NaHCO3 solution (25 ml), dried (MgSO4), and the solvent is removed under reduced pressure. The crude oil is purified by SGCC (5% MeOH:CH2CI2) giving 17(15).
(e) Svnthesis of Compound 18(15): To a solution of 17(15) (300 mg, 339 mmol) in methylene chloride:MeOH (3 ml:1 ml) at -78°C is bubbled O3 in O2 until a blue color persists. To remove residual O3, pure O2 is bubbled through until the solution turns clear. PPh3 (98 mg, 372 mmol) is added and the reaction mixture is warmed to 23°C and stirred for 24 h. The reaction mixture is evaporated and partitioned between a saturated NaHCO3 solution (50 ml) and CH2CI2 (5 ml). The aqueous phase is extracted with CH2CI2 (2 x 30 ml) and the combined organic phases are dried and concentrated under reduced pressure. The crude oil is used directly without further purification.
The aldehyde prepared above is dissolved in acetone (3 ml) and cooled to 0°C. Jones reagent is added drop-wise until a orange color persists. iPrOH (1 ml) is added to quench any excess Jones reagent and the reaction mixture is then partitioned between methylene chloride (50 ml) and 1 N HCI (50 ml). The aqueous layer is extracted with CH2CI2 (50 ml) and the combined organic phases are dried (MgSO4), concentrated under reduced pressure, and purified by silica gel flash chromatography (100% EtOAc) giving 18(15).
Example A24: Preparation of compound 23(15)
(a) Svnthesis of Compound 20(15): To a solution of the terminal olefin
(500 mg, 0.887 mmol; intermediate from 7(15)) in benzene (50 ml) is added PdCI2 (catalytic) and the solution is heated to reflux for 24 h. The reaction mixture is filtered through Celite, evaporated, and the crude oil is purified by silica gel chromatography (EtOAc:Hexane 1 :9 to 1:1) giving 20(15).
(b) Svnthesis of compound 21(15): Starting from a solution of 20(15) (230 mg, 0.407 mmol) in methylene chloride (20 ml) 21(15) is prepared according to Example A30(d).
(c) Svnthesis of compound 22(15): To a solution of 16(15) (65 mg, 0.203 mmol), 21(15) (150mg, 0.264 mmol), NMM (45 ml, 0.407), and HOBt (41.1 mg, 0.305 mmol) in CH2Cι2 (3 ml) at 0°C is added EDC (60.1 mg, 0.305 mmol). The reaction mixture is warmed to 23°C and stirred for 24h. The reaction mixture is diluted with EtOAc ( 50 ml) and washed successively with a 5% citric acid solution (20 ml) and saturated NaHCO3 (20 ml). The solvent is re-
moved under reduced pressure, dried (MgSO9), and the crude oil is purified by silica gel chromatography (EtOAc:Hexane 1 :3 to 3:1) giving 22(15).
(d) Svnthesis of Compound 23(15): Starting from a solution of 22(15) (100 mg, 0.114 mmol) in methylene chloride (10 ml) 23(15) is prepared according to Example A30(d) wherein the last purification step is silica gel flash chromatography (EtOAc:HOAc 95:5).
Example A 25: Preparation of compound 26(15)
To a solution of 25(15)
(100 mg, 0.386 mmol) obtained following Cappi et al. [Angew. Chem. 108:2501 (1996)] in MeOH (2 ml) at 23°C is added succinic anhydride (38 mg, 0.386 mmol) and the reaction mixture is stirred for 24 h at 23βC. The reaction mixture is concentrated under reduced pressure and the crude oil is purified by silica gel chromatography giving 26(15).
Example A 26: Preparation of Compound 28(15)
Starting from 25(15) and glutaric anhydride (44 mg, 0.386 mmol) 28(15) is prepared in analogy to Example A25.
Example A29: Preparation of methyl 3-allyloxy-2-amino-4,6-benzylidene-β-D- galactopyranoside 12(3)
To a solution of methyl β-D-galactopyranoside (10 g, 51.5 mmol) in CH3CN (250 ml) is added benzaldehyde dimethyl acetal (15.6 ml, 103 mmol) followed by CSA (1.19 g, 5.15 mmol). After 30 min Et3N (1 ml) is added and the solvent is removed under reduced pressure and the crude solid is recrystallized from hot MeOH affording the benzylidene acetal.
To a solution of the above galactose benzylidene acetal (4.7g, 16.7 mmol) in toluene (55 ml) is added Bu2SnO (4.56 g, 18.3mmol) and the solution is dehydrated using a Dean-Stark trap (130°C, 2 h). The reaction mixture is cooled to 70°C and TBAI (4.3 g, 11.7 mmol) is
added followed by allylbromide (2.18 ml, 25 mmol). The solution is stirred at 130°C for 24 h before being cooled to 23°C and partitioned between EtOAc (200 ml) and saturated NaHCO3 (200 ml). The aqueous layer is extracted with EtOAc (2 x vol) and the combined organic layers are dried (MgSO4), concentrated under reduced pressure, and chromatographed (1 :1 to 100% EtOAc Hexane) giving the product intermediate. To a solution of (COCI)2 (209 μl, 2.40 mmol) in CH2CI2 (4 ml) at -78 C is added DMSO (341 μl, 78.1 mmol). The reaction mixture is warmed to 0°C for 5 min and then re-cooled to -78°C. 3-Allyl-4,6-benzylidene-2-hydroxy β-D-methylgalactopyranoside (704 mg, 2.19 mmol) is dissolved in CH2CI2 (4 ml) and added slowly drop-wise. The reaction mixture is stirred for 30 min and DIPEA is added (1.48 ml, 10.9 mmol). The reaction mixture is warmed to 23°C, diluted with CH2CI2 (100 ml), washed with saturated NaHCO3 (50 ml), and dried (MgSO4). The crude product is used directly in the next step without further purification. To a solution of the above ketone in MeOH (20 ml) is added NH4OAc until the solution is saturated. Sodium cyanoborohydride (116 mg, 2.19 mmol) is added and the reaction mixture is stirred for 48 h. The reaction mixture is partitioned between EtOAc (100 ml) and saturated NaHCO3 (50 ml) and the aqueous layer is further extracted with EtOAc (2 x 50 ml). The combined organic layers are dried (MgSO4), concentrated under reduced pressure, and chromatographed (5% MeOH/ CH2CI2) giving 12(3).
Example A30: Preparation of methyl-2-[N-(2,3,4,6-tetrabenzyloxy-α-D-mannopyran- oside)carbonyl]amino-3-[(2-acetic acid)oxy]-4,6-O-dibenzylidine-galac- topyranoside 13(3)
(a) Svnthesis of -O-acetyl-1-allyl-2.3.4-tri-O-benzyl-α-D-mannopyranoside 8(3): To a solution of methyl 2,3,4,6-tetra-O-benzyl-α-mannoside (0.69 mmol) in CH3CN (1.4 ml) is added allyltrimethylsilane (1.45 mmol) at 0CC under argon. To the mixture is added TMSOTf (0.35 mmol) and the reaction is kept stirring under the same temperature overnight, then warmed up to 25°C. To the mixture is added acetic anhydride (1 ml) drop by drop. After 5 min, the reaction is diluted with CH2CI2 (10 ml) and the resulting solution is quenched by saturated NaHCO. The aqueous layer is extracted with CH2CI2 (2 x 10 ml) and the combined organic layers are washed with brine, dried with MgSO4, filtered, evaporated and purified by column chromatography to provide 8(3).
(b) Svnthesis of Compound 9a(3): To a solution of 8(3) (1.00 g, 2.11 mmol) is added 0.3 equivalents of sodium methoxide in 1.0 M methanol and is stirred at 25°C for 6 h; the
solution is concentrated and to the crude is added 95% NaH (0.10 g, 2.74 mmol) at 0°C under argon. After 30 min, to the mixture is added BnBr (0.84 ml, 2.74 mmol) followed by TBAI (37.4 mg, 0.11 mmol) and the resulting solution is warmed up to 25CC overnight. The reaction is quenched by H2O (10 ml), then extracted with EtOAc (3 x 10 ml) and the combined organic layers are washed with brine, dried with MgSO4, filtered, evaporated and purified by column chromatography (hexane to EtOAc/hexane = 1/20) to yield 9a(3).
(c) Svnthesis of 1-(1-propenyl)-2.3.4.6-tetra-O-benzyloxy-α-D-mannopyranoside 10(3): To a solution of 9a(3) (500 mg, 0.887 mmol) in benzene (50 ml) is added PdCI2 (catalytic) and the solution is heated to reflux for 24 h. The reaction mixture is filtered through Celite, evaporated, and the crude oil is purified by silica gel chromatography (EtOAc:Hexane 1 :9 to 1:1) giving 10(3).
(d) Svnthesis of 1-(2.3.4.6-tetra-O-benzyloxy-α-D-mannopyranosyl)-formic acid 11(3): To a solution of 10(3) (230 mg, 0.407 mmol) in CH2CI2 (20 ml) at -78°C is bubbled O3 until a blue color persists. To remove residual O3, pure O2 is bubbled through until the solution turns clear. DMS (1.0 ml) is added and the reaction mixture is warmed to 23°C and stirred for 24 h. The reaction mixture is concentrated under reduced pressure. The crude oil is used directly without further purification.
The aldehyde prepared above is dissolved in acetone (5 ml) and cooled to 0°C. Jones reagent is added drop-wise until an orange color persists. 'PrOH (1 ml) is added to quench any excess Jones reagent and the reaction mixture is then partitioned between EtOAc (50 ml) and 1 N HCI (50 ml). The aqueous layer is extracted with EtOAc (50 ml) and the combined organic phases are dried (MgSO4), concentrated under reduced pressure, and purified by silica gel flash chromatography (EtOAc:Hexane:HOAc 3:1 :0.01 ) giving 11(3).
(e) Svnthesis of 13(3): To a solution of 12(3) (65 mg, 0.203 mmol), 11(3) (150 mg, 0.264 mmol), NMM (45 μl, 0.407), and HOBt (41.1 mg, 0.305 mmol) in CH2CI2 (3 ml) at 0°C is added EDC (60.1 mg, 0.305 mmol). The reaction mixture is warmed to 23°C and stirred for 24 h. The reaction mixture is diluted with EtOAc (50 ml) and washed successively with a 5% citric acid solution (20 ml) and saturated NaHCO3 (20 ml). The solvent is removed under reduced pressure, dried (MgSO4), and the crude oil is purified by silica gel chromatography (EtOAc:Hexane 1 :3 to 3:1 ) giving 13(3).
Example A31 : Preparation of dibenzyl N-[1-(6-O-hexadecanyl-2,3,4-tri-0-benzyl-α-D- mannopyranosyl)]-acetyl-L-glutamate 17(3)
(a) Svnthesis of 1 -allyl-6-O-hexadecanyl-2.3.4-tri-O-benzyl-α-D-mannopyranoside 9b(3V. To a solution of acetate 8(3) (1.00 g, 2.11 mmol) is added 0.3 equivalents of sodium methoxide in 1.0 M methanol and is stirred at 25°C for 6 h; the solution is concentrated and to the crude is added 95% NaH (0.10 g, 2.74 mmol) at 0βC under argon. After 30 min, to the mixture is added 1 -bromohexadecane (0.84 ml, 2.74 mmol) followed by TBAI (37.4 mg, 0.11 mmol) and the resulting solution is warmed up to 25°C overnight. The reaction is quenched by H2O (10 ml), then extracted with EtOAc (3 x 10ml) and the combined organic layers are washed with brine, dried with MgSO , filtered, evaporated and purified by column chromatography (hexane to EtOAc/hexane = 1/20) to yield 9b(3).
(b) Svnthesis of 17(3): Step (a): Starting from a solution of 9b(3) (679 mg, 1.20 mmol) in CH2CI2:MeOH (8 ml:4 ml) the corresponding carboxylic acid intermediate is prepared according to Example A30(d).
Step (b): To a solution of carboxylic acid intermediate (50 mg, 0.086 mmol), H-Glu-(OBn)2 • pTsOH (0.095 mmol), HOBt (12.8 mg, 0.095 mmol), and NMM (10.3 μl, 0.095 mmol) in CH2CI2, (500 μl) at 0°C is added EDC (18 mg, 0.095 mmol). The reaction is allowed to stir for 24 h before being diluted with CH2CI2 (50 ml) and washed successively with a citric acid solution (25 ml), saturated NaHCO3 solution (25 ml), and brine (25ml). The organic phase is dried (MgSO ), concentrated under reduced pressure, and purified by silica gel chromatography (EtOAc:Hexane 1 :1 ) giving 17(3).
(Alternatively, the following alkyl halide or acyl halide may be used in lieu of 1 -bromohexadecane: 1-chloropropane, 1-chlorobutane, 1-chloropentane, 1-chlorohexane, 1 -chloro- heptane, 1 -chlorooctane, 1-chlorononane, 1-chlorodecane, 1-bromoundecane, 1-bromo- dodecane, 1-bromotridecane, 1 -bromotetradecane, 1-bromopentadecane, 1 -bromohexadecane, 1-bromooctadecane, 1-bromoeicosane, 1-bromodocosane, 2-bromomethyl-naph- thalene, 1-chloromethyl-naphthalene, 2-bromoethyl-benzene, l -bromo-3-phenyl-propane, heptanoyl chloride, octanoyl chloride, nonaoyl chloride, decanoyl chloride, undecanoyl chloride, lauroyl chloride, myristoyl chloride, palmitoyl chloride, heptadecanoyl chloride and stearoyl chloride)].
Example A32: Preparation of 18(3)
D-Mannose (1500 mg, 8.3 mmol) is added to 10 ml of allyl alcohol together with a catalytic amount (10 mg) of camphorsulfonic acid. The mixture is heated to 90°C overnight and then
the excess allyl alcohol is evaporated in vacuo. Flash chromatography of the residue (EtOAc:MeOH, 6:1 -4:1 ) gives 1400 mg (76%) of α-O-allylmannopyranoside. To a solution of the above compound is added 1.1 equivalents TBDPSOTf (1.1 equivalents) in anhydrous methylene chloride (.10 M) at 0°C and allowed to stir for 2 h. Next, 3.3 equivalents of sodium hydride are added, followed by 3.3 equivalents BnBr. The mixture is allowed to stir overnight at 0°C and extracted with CH2CI2 and washed with 1 N HCI, saturated NaHCO3, and brine, and purified by flash chromatography using EtOAc as eluent. Next, 1.1 equivalents of TBAF are added in anhydrous methylene chloride (.10 M) at 0°C and allowed to stir for 2 h. The mixture is then extracted with CH2CI2 and washed with ammonium chloride, saturated NaHCO3, and brine, and purified by flash chromatography using EtOAc as eluent.
Next, 1.1 equivalents of sodium hydride are added in anhydrous methylene chloride mixture (.10 M) at 0°C and then 1.1 equivalents of either an alkyl halide or acyl halide as mentioned in Example A31(a) are added and allowed to stir for 2 h. The mixture is then extracted with CH2CI2 and washed with ammonium chloride, saturated NaHCO3, and brine, and purified by flash chromatography using EtOAc as eluent.
To a solution of the above compound (482 mg, 2.2 mmol) in CH2CI2:MeOH (1 :4) is bubbled O3 at -78°C in the presence of a catalytic amount of NaHCO3. After the blue color appears, an excess (3 eq) of PPh3 is added. After stirring overnight, an extractive workup is performed (CH2CI2/water), the aqueous portion is evaporated affording 18(3).
Example A33: Preparation of 18a(3)
The ozonolysis of 9a(3) is performed as described above. The aldehyde product (2 mmol, 1.1 g) is dissolved in a 3:1 mixture of THF and water and hydrogenated overnight at 1 atm in the presence of a catalytic amount of Pd-C. After filtration through Celite and evaporation of the solvent, the deprotected aldehyde 18a(3) is isolated.
Example A34: Preparation of compound 63(3)
(a) Svnthesis of allyl 6-tosyl-6-deoxy-D-mannopyranoside 60(3): To a solution of allyl mannopyranoside (6.6 g, 30 mmol; formed by refluxing neat allyl alcohol with mannose in the presence of .01 equivalents CSA or equivalent) in dry pyridine (75 ml) at 0°C is added tosyl chloride (10.3 g, 54 mmol) dissolved in CH2CI2, and the reaction is stirred at 0°C for 16 h and at RT for 4h. The reaction mixture is extracted with CH2CI2 and washed with 1 N HCI,
saturated NaHCO3, and brine, and purified by flash chromatography using EtOAc as eluent to yield 60(3).
(b) Svnthesis of allyl 6-azido-6-deoxy-D-mannopyranoside 61(3): To a solution of 60(3) (1.6 g, 9.3 mmol) in DMF (50 ml) is added 10 equiv (4.1 g) of NaN3, and this mixture is refluxed overnight, the solvent removed in vacuo, and the residue chromatographed in SiO2 using EtOAc as eluent to yield 61(3).
(c) Svnthesis of Compound 62(3): A solution of 61(3) (482 mg, 2.2 mmol) and catalytic amount of NaHCO3 (10 mg) in CH2CI2/MeOH (4/1 , 40 ml) is cooled to -78°C. O3 is bubbled through the solution until a blue color is observed (10 min) then N2 is bubbled through the solution until it becomes colorless. Dimethyl sulfite (577 mg, 6.6 mmol) is added and the mixture is warmed to RT and stirred overnight. After filtrated, the solvent is evaporated under reduced pressure. The residue is dissolved in water and washed with ether. The water layer is lyophiiized to yield 62(3).
(d) Svnthesis of Compound 63(3): 62(3) (330 mg, 1.5 mmol) and DHAP (0.5 mmol) are dissolved in Tris buffer (50 mM, pH 7.4) 10 ml. The pH is adjusted to 7.0 by adding 1 N NaOH and then 200 u of RAMA (Sigma) is added. The reaction mixture is shaken under nitrogen at RT. The progress of the reaction is followed by DHAP consumption (UV assay) until >90% of the DHAP has been consumed. The pH is adjusted to 7.5 and BaCI2-H2O (1.0 M, 2 mmol) is added slowly. The cloudy mixture is kept at 4°C for 1 h and the precipitates are removed by centrifugation. To the supernatant 2 volumes of acetone are added and the mixture is stored at 9°C for 2 h. The precipitates are collected by centrifugation and the supernatant is discarded. The pellet is treated with Dowex-50 H+ to pH 2 (the solid is dissolved) and the resin is filtered off. The pH of the filtrate is adjusted to 7.0-7.5 by adding 0.2 N NaOH. Lyophilization yields 63(3).
Example A35: Preparation of 68(3)
(a) Svnthesis of 6-O-acetyl-1-allyl-2.3.4-tri-O-benzyl-α-D-mannopyranoside 65(3): To a solution of methyl 2,3,4,6-tetra-O-benzyl-α-mannoside (0.69 mmol) in CH3CN (1.9 ml) is added allyltrimethylsilane (1.45 mmol) at 0°C under argon. To the mixture is added TMSOTf (0.35 mmol) and the reaction is kept stirring under the same temperature overnight, then warmed up to 25°C. To the mixture is added acetic anhydride (1 ml) drop by drop. After 5 min, the reaction is diluted with CH2CI2 (10 ml) and the resulting solution is quenched by saturated NaHCO3. The aqueous layer is extracted with CH2CI2 (2 x 10 ml) and the combined organic
layers are washed with brine, dried with MgSO , filtered, evaporated and purified by column chromatography to provide the acetate.
The crude acetate is dissolved in MeOH and a catalytic amount of 25% NaOMe by weight is added in MeOH. After 2 h Dowex H+ resin is added until the pH of the solution is approximately 1 -2. The residue is then dissolved in CH2CI2 and the solution is washed with 5% aq. citric acid solution , sat. NaHCO3 soln., and brine. This solution is then dried over Na2SO4 and concentrated under reduced pressure. The crude material is purified by flash chromatography with silica gel using 25%-35% ethyl acetate in hexane as the eluent. The product is dissolved in methylene chloride (1.0 M) and exposed to PPh3 (1.1 equivalents) and DEAD (1 equivalent) and finally (PhO)2PON3 (1.1 equivalents) is added dropwise at 0°C and the mixture is stirred for 1 -2 h. The residue is dissolved in CH2CI2 and the solution is washed with 5% aq. citric acid solution, sat. NaHCO3 soln., and brine. This solution is then dried over Na2SO, and concentrated under reduced pressure. The crude material is purified by flash chromatography with silica gel using 25%-35% ethyl acetate in hexane as the eluent to provide 65(3).
(b) Svnthesis of N-(di-O-benzylαlutamyl)-2-f(6-azido-2.3.4-tri-O-benzyloxy)-α-D-manno- pyranosvDl-ethamide 67(3): To a stirred solution of 65(3) (2.05 g, 4.1 mmol) and NMO (480 mg, 4.1 mmol) in 36 ml of a 9:2:1 mixture of acetone: tert-butanol:H2O, is added OsO4 (380 μl, 0.004 mmol) as a 2.5 wt% solution in tert-butanol. After stirring overnight, the reaction is quenched by the addition of 1 g Na2S2Os, 10 g Florisil and 25 ml of H2O. After 30 min, the reaction mixture is concentrated under reduced pressure and the residue is treated with EtOAc and water. The solution is decanted away from the Florisil and the aqueous portion is extracted four times with EtOAc. The combined organic extracts are dried over MgSO4 and concentrated under reduced pressure. The diol is immediately used in the next reaction.
To a stirred solution of the diol in 55 ml of THF and 40 ml of H2O, is added NalO4 (1.4 g, 6.5 mmol). After 15 min the reaction is quenched by the addition of H2O and EtOAc. The aqueous portion is extracted three times with EtOAc. The combined organic extracts are dried over Na2SO4 and concentrated under reduced pressure. The aldehyde is then used immediately in the next reaction.
To a stirred 0°C solution of the aldehyde in 40 ml of acetone, is added Jones reagent until an orange color persists. Tic analysis indicates the complete consumption of the starting material. The reaction is quenched with isopropanol, 5 g of celite is added and the reaction
is stirred for 20 min. The solution is decanted into a separatory funnel and EtOAc is added. The aqueous portion is extracted three times with EtOAc. The combined organic extracts are dried over MgSO4 and concentrated under reduced pressure. The acid is sufficiently pure for use in the next reaction.
To a stirred, 0°C solution of the above carboxylic acid, amino acid (2.25 g, 4.5 mmol), HOBt (609 mg, 4.5 mmol) and NMM (496 μl, 4.5 mmol) in 60 ml of CH2CI2, is added EDC (865 mg, 4.5 mmol). The reaction is allowed to slowly warm to RT overnight and the reaction is quenched by the addition of H2O and CH2CI2. The aqueous portion is extracted three times with CH2CI2. The combined organic extracts are dried over Na2SO4 and concentrated under reduced pressure. The residue is purified by flash chromatography on silica gel using 35% EtOAc in hexane to provide 67(3).
(c) Synthesis of Compound 68(3): To a stirred solution of 67(3) (666 mg, 0.8 mmol) and PPh3 (336 mg, 1.28 mmol) in 20 ml of THF, is added H2O (23 μl, 1.28 mmol). After stirring overnight, hexanoic acid (0.96 mmol), HOBt (130 mg, 0.96 mmol) and NMM (106 μl, 0.96 mmol) are added. After cooling the mixture to 0°C, EDC (184 mg, 0.96 mmol) is added. The cold bath is removed after 10 min and the mixture is vigorously stirred to dissolve the remaining solid material. After stirring overnight, the reaction is quenched with 5% aqueous citric acid and Et2O is added. The aqueous portion is extracted with Et2O three times. The combined organic extracts are washed with sat. aqueous NaHCO3 soln. and brine, dried over MgSO4 and concentrated under reduced pressure. The residue is purified by flash chromatography on silica gel using 5% MeOH in CH2CI2 as the eluent to provide 68(3).
Example A36: Preparation of 71(3)
To a stirred solution of 68(3) in 2 ml of HOAc are added 2 drops of H2O, a catalytic amount of 10% Pd/C and H2 gas. After stirring for 1 day, the catalyst is filtered off through a pad of celite and the pad is rinsed with HOAc. The filtrate is concentrated under reduced pressure to provide 71(3).
Example A37: Preparation of 78(3)
(a) Svnthesis of N-(O-allylhexanoate)-2-(2.3.4-tri-O-benzyl-α-L-fucopyranosyl)ethylamine 73(3): H
2N(CH
2)
5C(O)OCH
2CHCH
2 (1 g, 5.8 mmol) is dissolved in 20 ml of MeOH and the pH of the solution is adjusted to pH 6 with glacial acetic acid. To this solution is added aldehyde
(533 mg, 1.3 mmol; aldehyde is synthesized via standard glycosylation conditions using 1 - methoxy-tribenzyl-fucose and allytrimethylsilane (1.1 equivalents, THF (.5 Molar), TMSOTf (.1 equivalent) at 0°C for 5 h) followed by NaCNBH3 (36 mg, 0.58 mmol). After 1 h the solution is concentrated under reduced pressure and the residue is treated with EtOAc and water. The pH of the solution is adjusted to pH 2 with 1 N HCI and the aqueous portion is extracted three times with EtOAc. The aqueous portion is then treated with solid KOH to adjust the pH to 10. The aqueous portion is again extracted three times with EtOAc and both organic portions are combined, dried over Na2SO4 and concentrated under reduced pressure. The residue is purified by flash chromatography on silica gel using 7% MeOH in CH2CI2 to provide 73(3).
(b) Svnthesis of (25.3S)-2-tert-butoxycarbony!amino-3.4-dibenzv!oxy-butanoic acid 74(3): To a stirred 0°C solution of 73(3) (992 mg, 2.3 mmol) in 20 ml of THF is added a 0°C solution of LiOH (23 ml, 5.7 mmol, 0.25 M in EtOH:H2O (3:1 )). The reaction is kept overnight at 4°C. Then the mixture is acidified to pH 2 with 1 N HCI and EtOAc is added. The aqueous portion is extracted with EtOAc three times. The combined organic extracts are dried over Na2SO4 and concentrated under reduced pressure to provide 74(3).
(c) Svnthesis of N-(O-allylhexanoate)-1-((2S.3S)-3,4-dibenzyloxy-2-tert-butoxycarbonyl- amino)-butyridiamidyll-2-(2.3.4-tri-C-benzyl-α-L-fucopyranosyl)ethane 75(3): To a stirred 0°C solution of 73(3) (31 mg, 0.05 mmol), 74(3) (20.4 mg, 0.05 mmol), HOBt (7.9 mg, 0.05 mmol) and NMM (6.0 μl, 0.05 mmol) in 10 ml of CH2CI2 is added HBTU (20.9 mg, 0.05 mmol). After warming to RT overnight, the reaction is quenched with 5% aqueous citric acid and CH2CI2 is added. The aqueous portion is extracted with CH2CI2 twice. The combined organic extracts are washed with sat. aqueous NaHCO3 soln. and brine, dried over Na2SO4 and concentrated under reduced pressure. The residue is purified by flash chromatography on silica gel using 20%-35% EtOAc in hexane as the eluent to provide the coupled adduct 75(3).
(d) Svnthesis of Compound 76(3): 75(3) (1.0 mmol) is dissolved in a 50:50 mixture of CH2CI2:TFA and the mixture is cooled to 0°C. After 30 min, the residue is concentrated to
remove the excess TFA and CH2CI2 and the residue is rinsed with CHCI3 and concentrated to remove any traces of TFA. The TFA amine salt is the one used in the general procedure for coupling a carboxylic acid and an amine, using an additional equivalent of NMM. To the reaction mixture is added, a carboxylic acid or succinate ester of the acid (0.96 mmol), HOBt (130 mg, 0.96 mmol) and NMM (106 μl, 0.96 mmol). After cooling the mixture to 0°C, EDC (184 mg, 0.96 mmol) is added. The cold bath is removed after 10 min and the mixture is vigorously stirred to dissolve the remaining solid material. After stirring overnight, the reaction is quenched with 5% aqueous citric acid and Et2O is added. The aqueous portion is extracted with Et2O three times. The combined organic extracts are washed with sat. aqueous NaHCO3 soln. and brine, dried over MgSO4 and concentrated under reduced pressure. The residue is purified by flash chromatography on silica gel using 5% MeOH in CH2CI2 as the eluent to provide amide 76(3).
(e) Svnthesis of Compound 77(3): To a stirred solution of 76(3) (666 mg, 0.8 mmol) and (Ph3)4Pd (336 mg, 1.28 mmol) in 20 ml of THF, is added H2O (23 μl, 1.28 mmol). After stirring overnight, tic analysis indicates the complete consumption of the starting material to provide 77(3).
(f) Svnthesis of Compound 78(3): To a stirred 0°C solution of 77(3) (1.0 mmol), HOBt (1.2 mmol), butyl amine (2.0 mmol) and NMM (2.5 mmol) in CH2CI2 (0.5 M) is added EDC (1.3 mmol). After stirring overnight and subsequent warming to RT, sat. NaHCO3 soln. and CH2CI2 are added to the reaction mixture. The aqueous portion is extracted twice with CH2CI2. The combined organic fractions are washed with 1 N HCI and brine, dried over Na2SO4 and concentrated. The crude residue is purified by flash chromatography in silica gel using ethyl acetate/hexane as the eluent affording 78(3).
[Alternatively, the following amines can be used in the procedure: butyl amine, amyl amine, hexyl amine, heptyl amine, octyl amine, nonylamine, decylamine, undecylamine, dodecyl- amine, tridecylamine, 1-tetradecylamine, pentadecylamine, hexadecyl amine, octadecyl amine, 1 -amino naphthalene, 2-amino naphthalene, 2-amino-2-naphthol perhydrochloride, 4-pentyl aniline, 4-hexyl aniline, 4-heptyl aniline, 4-octyl aniline, 4-decyl aniline, 4-dodecyl aniline, 4-tetradecyl aniline and 4-hexadecylaniline].
Example A38: Preparation of 81(3)
(a) Synthesis of compound 80(3): To a solution of 64(3)
(2.11 mmol) in DMF (7 ml) is added 95% NaH (2.74 mmol) at 0°C under argon. After 30 min, the mixture is added 1 -bromohexadecane (2.74 mmol; alternatively the alkyl halides and acid chlorides mentioned in Example A31 (a) can be used in the procedure) followed by the addition of TBAI (2.74 mmol) and the resulting solution is warmed up to 25 °C overnight. The reaction is quenched by H2O (10 ml), then extracted with EtOAc (3 x 10 ml) and the combined organic layers are washed with brine, dried with MgSO4, filtered, evaporated and purified by column chromatography (hexane to EtOAc/hexane = 15 1/20) to yield 80(3). (b) Svnthesis of compound 81(3): To a solution of 80(3) (1.62 mmol) in 1/1 acetone/H2O (10 ml) is added NMO (0.24 g, 2.05 mmol) followed by a solution of OsO4 in t-BuOH (0.2 g, 2.5% w/w) at 25 °C. The solution is stirred for 16 h and the reaction is quenched by the addition of Na2S2O3 (0.2 g), Florisil (1 g) and H2O (10 ml). The mixture is acidified to pH = 1 with 1 N HCI and the resulting solution is extracted with EtOAc (3 x 20 ml). The combined organic layers are washed with saturated NaHCO3 and brine, dried with MgSO4, filtered and evaporated to yield a 1/1 mixture of diastereomeric diols.
To a solution of above diols in THF (8 ml) is added NalO4 (0.61 g) in one portion. The stirred slurry is added H2O (8 ml) over 5 min and the mixture is kept stirring for 2 h. The resulting solution is extracted with EtOAc (3 x 20 ml) and the combined organic layers are washed with brine, dried with MgSO l filtered and evaporated to yield the crude aldehyde. The above aldehyde is dissolved in acetone (7 ml) and the solution is cooled to 0°C. The mixture is added Celite (0.8 g) in one portion followed by the addition of Jones reagent drop by drop until a orange color persists. i-PrOH (1 ml) is added to quench any excess Jones reagent and the reaction mixture is then partitioned between EtOAc (50 ml) and 1 N HCI (50 ml). The aqueous layer is extracted with EtOAc (2 x 50 ml) and the combined organic phases are dried with (MgSO4), concentrated and purified by silica gel flash chromatography (EtOAc/hexane/AcOH = 3/1/0.01) to yield the carboxylic acid. To a solution of the above carboxylic acid (0.363 mmol) in CH2CI2 (3 ml) is added BnO-Glu(OBn)-NH2 • p-TsOH (200 mg, 0.399 mmol), triethylamine (56 μl, 0.399 mmol), HOBt (54.0 mg, 0.399 mmol) and EDC (76.4 mg, 0.399 mmol) at 25°C under argon. The
reaction is allowed to stir for 24 h before being diluted with CH2CI2 (20 ml) and washed successively with a 1 N hydrochloric acid solution (15 ml), saturated NaHCO3 solution (15 ml) and brine (15 ml). The organic phase is dried with MgSO4, concentrated and purified by silica gel chromatoaraphy to yield 81(3).
Example A39: Preparation of compound 83(3)
(a) Svnthesis of compound 82(3): The preparation from 80(3) is followed by the procedure according to Example A38 using instead 3-carboxyethyl aniline to afford 82(3).
(b) Svnthesis of compound 83(3): An ice-cold solution of 0.25 M LiOH in 75% MeOHaq (5.3 ml) is added to a solution of 82(3) (230 mg, 0.27 mmol) in THF (4 ml) and the mixture is vigorously stirred for 2 days at 4°C. The resulting solution is acidified with 1 N HCI to pH 1-2 and extracted with EtOAc (3 x 10 ml). The combined organic layers are washed with brine, dried with MgSO , filtered, evaporated and purified by a short column chromatography to yield 83(3).
Example A40: Preparation of 83a(3)
Starting from 64(3) and Br-d6H33 83a(3) is prepared according to Example A38.
Example A41 : Preparation of 102i(3)
(a) Svnthesis of C-allylmannose 107(3): To a solution of α-D-mannose pentaacetate (1.0 g, 2.56 mmol) at 0°C is added allyltrimethylsilane (1.22 ml, 7.69 mmol) followed by BF3-Et2O (1.5 ml, 12.8 mmol). The reaction mixture is allowed to warm to 23°C and TMSOTf (100 ml) is added and the solution is stirred for 24h. The mixture is poured into a saturated NaHCO3 solution (50 ml) and the organic phase is diluted with CH2CI2 (50 ml). The aqueous phase is extracted with CH2CI2 (2 x 25 ml) and the combined organic phases are dried (MgSO4), filtered, and concentrated under reduced pressure to give the crude oil which is used directly in the next step without further purification.
The prepared C-allylglycoside from above is dissolved at 23°C in anhydrous methanol (30 ml) and NaOMe (25 wt% in MeOH, 5 ml) is added. After 2 h the reaction mixture is quenched by the addition of Dowex resin (50W-X8). The resin is removed by filtration and the reaction mixture is concentrated under reduced pressure. The crude oil is purified by silica gel flash chromatography (CH2CI2/MeOH, 9:1) giving tetraol 107(3) as a mixture of α and β anomers (8:1).
(b) Svnthesis of tetrabenzyl C-allylmannose: To a solution of 107(3) (1.96 g, 9.61 mmol), BnBr (8 ml, 67.3 mmol), and TBAI (177 mg, 048 mmol) in THF (20 ml) at 0°C is added NaH (2.35 g, 57.6 mmol). The cooling bath is removed and the reaction mixture is allowed to stir for 24 h. The reaction is diluted with EtOAc (50 ml) and poured into a saturated NH4CI solution (50 ml). The aqueous phase is extracted with EtOAc (2 x 30 ml) and the combined organic phases are dried (MgSO4) and concentrated under reduced pressure providing the crude oil. Purification by silica gel flash chromatography (hexane:EtOAc, 100% to 9:1 to 1:1) gives the desired product.
(c) Svnthesis of tetrabenzyl carboxylic acid 108(3): To a solution of the above prepared terminal olefin (679 mg, 1.20 mmol) in CH2CI2:MeOH (8 ml:4 ml) at -78°C is bubbled O3 in O2 until a blue color persists. To remove residual O3, pure O2 is bubbled through until the solution turns clear. DMS (1.7 ml, 24.0 mmol) is added and the reaction mixture is warmed to 23°C and stirred for 24 h. The reaction mixture is evaporated and partitioned between a saturated NaHCO3 solution (50 ml) and EtOAc (5 ml). The aqueous phase is extracted with EtOAc (2 x 30 ml) and the combined organic phases are dried and concentrated under reduced pressure. The crude oil is used directly without further purification. The aldehyde prepared 109(3) is further reacted according to the procedure described in Example A30(d) giving the carboxylic acid 108(3).
(d) To a solution of carboxylic acid 108(3) (50 mg, 0 086 mmol), H-Gly-OBn • pTsOH (32 mg, 0.095 mmol; also HCI salts can be used in lieu of the pTsOH salt), HOBt hydrate (12.8 mg, 0.095 mmol), and NMM (10.3 ml, 0.095 mmol) in CH2CI2 (500 ml) at 0°C is added EDC (18 mg, 0.095 mmol). The reaction is allowed to stir for 24 h before being diluted with CH2CI2 (50 ml) and washed successively with a 5% citric acid solution (25 ml), saturated NaHCO3 solution (25 ml), and brine (25 ml). The organic phase is dried (MgSO ), concentrated under reduced pressure, and purified by silica gel chromatography (EtOAc:Hexane 1:1) giving 1021(3).
Example A42: Preparation of 103i(3)
1031(3) is prepared according to the procedure described in Example A41 coupling with
BnO-Tyr-NH2 • pTsOH.
Example A43: Preparation of 104i(3)
1041(3) is prepared according to the procedure described in Example A41 coupling with BnO-Glu(OBn)-NH2 • pTsOH..
Example A44: Preparation of ethyl (2S,3/7)-2,3-dihydroxy-4-(tetra-O-benzyl-α-D- mannopyranosyl)-butanoate 113(3)
To a suspension of LiCI (67 mg, 1.58 mmol) and triethyl phosphonoacetate (0.30 ml, 1.51 mmol) in dry CH3CN (12 ml) is added DBU (185 μl, 1.24 mmol) followed by (2-(tetra-O- benzyl-α-D-mannopyranosyl)acetaldehyde 109(3) (700 mg, 1.235 mmol) at 23°C and the reaction is stirred for 40 min. The mixture is taken up in ether, extracted with 0.5 N HCI, saturated NaHCO3- sol. and brine, dried over MgSO4. After removal of the solvent in vacuo the residue is purified by SGCC (20% EtOAc in hexanes) to give the desired α,β-unsatura- ted ester.
The α.β-unsaturated ester (211 mg, 331 μmol) is subjected to the general procedure described for the asymmetric dihydroxylation reaction (AD-reaction) to provide diol 113(3).
B Preparation of the mimetica
Example B1 : Preparation of 1-(2-monosuccinamidyl-L-threonine)-2-2(2-pheneth- oxy)-3-(α-L-fucopyranosyl)propane 1 [1a (2'R); 1b (2'S)]
According to the general deprotection procedure A 25a (33.7 mg, 34.5μmol) is deprotected and passed through the Anotop 25 membrane filter to give the title compound 1a (16.3mg, 90%) as a white solid. The corresponding diastereomer is obtained similarly by deprotection of pentabenzyl derivative 25b (47.0mg, 48.1 μmol) to afford 1b as a white solid. Data for 1a: Η NMR (400 MHz, D2O) δ 1.09 (3H, d, J = 6.4, Me-thr), 1.16 (3H, d, J = 6.3, H-6), 1.64 (1H, ddd, J = 14.5, 7.6, 4.1 , H-1'a), 1.75 (1 H, ddd, J = 15.0, 10.8, 4.6, H-1'b), 2.54-2.63 (4H, m, HO2CCH2CH2CONH), 2.77-2.89 (2H, m, OCH2CH2Ph), 3.22 (1H, br ddd, J = 13.8, 10.9, 5.4,
H-3'a), 3.41-3.49 (2H, m, H-2*. OCHHCH2Ph), 3.56 (1 H, dt, J = 6.6, 6.0, H-3'b), 3.62 (1 H, dd, J = 10.0, 3.3, H-3), 3.68 (1 H, br d, J = 2.8, H-4), 3.73 (1 H, dt, J = 9.9, 6.9, OCHHCH2Ph), 3.85 (1 H, dd, J = 9.8, 6.4, H-2), 3.86 (1H, m, H-5), 3.97 (1 H, br ddd, J =
10.5, 5.9, 4.6, H-1 ), 4.16 (1 H, dq, J = 6.4, 4.3, β-H-thr), 4.22 (1 H, d, J = 4.1 , α-H-thr), 7.25- 7.38 (5H, m, aromatic), 7.90 (ca. 1 H, t, J = 5.6, CONHCH2); 13C NMR (100 MHz, D2O) δ
18.06, 21.28, 29.06, 33.22, 38.25, 44.05, 44.17, 61.66, 69.36, 69.71 , 72.04, 73.30, 73.93, 74.82, 79.07, 128.95, 131.10, 131.48, 141.65, 174.68, 178.17, 180.91 ; HRMS calcd for CsC25H38N2Oιo (M+Cs) 659.1581 , found 659.1562.
Data for 1b: Η NMR (400 MHz, D2O) δ 1.15 (3H, d, J = 6.4, Me-thr), 1.18 (3H, d, J = 6.3, H- 6), 1.54 (1 H, br t, J = 11.6, H-1'a), 1.79 (1 H, br t, J = 12.9, H-1'b), 2.58 (4H, s, HO2CCH2CH2CONH), 2.87 (2H, t, J = 7.1 , OC^CJ± h), 3.20 (1H, br dt, J = 13.7, 5.0, H- 3'a), 3.39 (1H, br dt, J = 13.8, 4.7, H-3'b), 3.62 (1H, m, H-2'), 3.66 (1H, dd, J = 10.1 , 3.0, H- 3), 3.73 (1H, br d, J = 2.9, H-4), 3.77 (2H, br dt, J = 10.8, 6.8, OCtbCHzPh), 3.88 (1 H, dd, J = 10.0, 6.2, H-2), 3.91 (1 H, m, H-5), 4.01 (1H, m, H-1 ), 4.19 (1 H, d, J = 3.6, α-H-thr), 4.23 (1H, br dq, J = 6.4, 3.8, β-H-thr), 7.25-7.38 (5H, m, aromatic), 7.98 (ca. 1 H, t, J = 5.7, CONHCHz); 13C NMR (100 MHz, D2O) δ 18.05, 21 ,32, 29.23, 33.16, 38.02, 44.90, 45.01 , 61.68, 69.24, 69.53, 69.95, 72.23, 73.45, 74.04, 74.14, 76.77, 128.92, 131.08, 131.39, 141.35, 174.87, 174.95, 178.22; HRMS calcd for NaC25H3θN2O10 (M+Na) 549.2424, found 549.2412.
Example B2: Preparation of 1-(2-monosuccinamidyl-L-threonine)-2-(3-phenylprop- oxy)-3-(α-L-fucopyranosyl)propane [(2'R/S)] 2
Boc-carbamate 26 (94mg, 132μmol, 1 :1 mixture of diastereomers) is deprotected according to the general procedure and the obtained free amine is treated with N-Boc-O-benzyl-L- threonine (45mg, 145μmol), EDC (29mg, 152μmol), HOBt (21 mg, 157μmol) and NMM (32μl, 290μmol) in DCM (1.5ml) according to general procedure B for 7h to give the coupled
compound (101mg, 85%) as a white solid. Removal of the Boc group (general procedure) and subsequent treatment with monobenzyl succinate (26mg, 125μmol), EDC 25mg, 131 μmol), HOBt (18.5mg, 137μmol) and NMM (20μl, 182 μmol) in DCM (1.3 ml) according to general procedure B for 12h yields the pentabenzyl compound (109mg, 98%) as a pale yellow oil. The benzyl groups are removed according to general procedure A, the product is filtered through the Anotop 25 membrance filter and 2 is after lyophilization obtained as a white solid (1 :1 diastereomeric mixture.
1H NMR (400 MHz, D
2O) δ 1.13-1.19 (6H, Me-thr, H- 6), 1.61/1.75 (1 H, m, H-1 'a), 1.86 (3H, m, OCH
2CH
2CH
2Ph, H-1 'b), 2.57-2.67 (6H, m, OCH
2CH
2CH
2Ph,
3.28-4.28 (12H, m, H-1 , 2, 3, 4, 5, 2', 3", α, β-H-thr, OCHzCHzCHzPh), 7.28-7.36 (5H, m, aromatic);
13C NMR (100 MHz, D
2O) δ 18.08, 21.26/21.35, 28.82, 33.03, 33.40, 33.89/33.98, 45.03, 61.69, 69.25/69.42, 69.56/69.81 , 70.01 , 71.33, 72.13, 72.27, 73.98, 75.11 , 76.51 , 78.58, 128.50, 131.02, 131.10, 139.85, 175.06, 177.90, 178.13; HRMS calcd for CsC
26H
40N
2O
10 (M+Cs) 673.1737, found 673.1712.
Example B3: Preparation of (2S H(2S,3flH^'hydroxy-2-monosuccinamidyl-butyr- amidyl}-2-(3-phenylpropoxy)-3-(α-L-fucopyranosyl)-propane 3b
According to the general deprotection procedure A 28b (72.5 mg, 72 μmol) is deprotected and filtered through the Anotop 10 membrane filter to yield after lyophilization 3b as a white solid. 1H NMR (500 MHz, D2O) δ 1.14 (3H, d, J = 6.4, H-6), 1.58 (1 H, ddd, J = 14.8, 10.4, 2.7, H-1'a), 1.79-1.85 (3H, m, H-1'b, OCH2CH2CH2Ph), 2.46-2.56 (4H, m, HOzCCHzCHzCONH), 2.63 (2H, t, J = 7.5, OCH2CH2CH2Ph), 3.29 (1H, dt, J = 14.3, 5.4, H- 3'a), 3.33 (1 H, dt, J = 13.9, 5.2, H-3'b), 3.48 (1 H, dt, J = 13.9, 6.6, OCHHCH2CH2Ph), 3.56 (1 H, dd, J = 12.1 , 6.1 , γ-Ha-hthr), 3.57-3.73 (5H, m, H-3, 4, 2', OCHHCH2CH2Ph, -^Hb-hthr), 3.76 (1H, br q, J = 6.1 , β-H-hthr), 3.92 (2H, m, H-2, 5), 4.13 (1 H, ddd, J = 11.7, 6.0, 2.7, H- 1), 4.37 (1H, d, J = 7.2, α-H-hthr), 7.19-7.33 (5H, m, aromatic), 8.14 (1H, t, J = 6.0, CONHCHz); 13C NMR (125 MHz, CDCI3) δ 16.39, 27.62, 31.02, 31.70, 32.28, 43.16, 43.27,
56.21 , 63.14, 67.88, 68.33, 70.36, 70.56, 71.64, 72.33, 72.47, 74.84, 126.79, 129.32, 129.37, 134.01 , 172.47, 172.55, 175.54; Electrospray-MS: calcd for C26H41N2Ou (M+H) 557, found 557, calcd for C26H39N2O11 (M-H) 555, found 555.
Example B3': Preparation of 4
4 is prepared according to Example B3 starting from the corresponding protected compound.
Example B4: Preparation of (2S)-1 -(2-monosuccinamidyl-L-threonine)-2-(tetradecyl- aminocarbonylmethoxy)-3-(α-L-fucopyranosyl)propane 5b
32b (35.5mg, 31.5μmol) is deprotected according to the general procedure A to afford after filtration through the Anotop 25 membrane filter (MeOH) 5b as a white solid. Η NMR (400 MHz, CD3OD/CD3CO2D/D2O 25:5:1 ) δ 0.86 (3H, t, J = 7.0, (CH2)13CH3), 1.19 (3H, d, J = 6.3, Me-thr), 1.20 (3H, d, J = 6.3, H-6), 1.25 (22H, br s, CH2CH2(CH2),ιCH3), 1.50 (2H, m, CONHCH2CH2(CH2)n), 1.74 (1 H, br ddd, J = 14.7, 9.9, 2.8, H-1 'a), 1.87 (1 H, br ddd, J = 14.4, 11.7, 2.7, H-1'b),2.54-2.73 (4H, m, HO2CCH2CH2CONH), 3.21 (2H, dd, J = 7.4, 5.5, CONHCH2CH2), 3.39 (2H, d, J = 5.0, H-3*), 3.64 (1 H, m, H-2'), 3.66 (1H, dd, J = 9.7, 3.2, H- 3), 3.71 (1 H, br s, H-4), 3.79 (1 H, br q, J = 6.3, H-5), 3.95 (1 H, dd, J = 9.5, 5.9, H-2), 4.06 (1H, d, J ■*= 15.2, OCHHCONH), 4.12 (1 H, d, J = 15.1 , OCHHCONH), 4,13 (1 H, m, H-1), 4.26 (1H, d, J = 3.2, α-H-thr), 4.31 (1 H, dq, J = 6.4, 3.3, β-H-thr); 13C NMR (100 MHz,
CD3OD/CD3CO2D/D2O 25:5:1) δ 14.47, 16.77, 20.21 , 23.57, 27.84, 28.41 , 30.27, 31.34, 33.87, 40.12, 43.54, 60.38, 67.95, 68.70, 69.23, 71.74, 72.69, 72.76, 77.26, 172.87, 173.29, 175.62, 177.09,; HRMS calcd for NaC33H61N3On (M+Na) 676.4384, found 676.4380
Example B5: Preparation of (2S)-1 -(2-monosuccinamidyl-L-threonine)-2-dimyristoyl- serinolcarbonyimethoxy)-3-(α-L-fucopyranosyl)propane 6b
34b (32.8mg, 23.0μmol) is deprotected according to the general procedure A. The reaction is first filtered through a celite pad with H2O to remove the transesterified side product (4.2mg). Afterwards, the filter cake is washed with MeOH, the solution is filtered through the membrane filter, the solvent is removed in vacuo and a emulsion of the remaining oil in H2O is lyophilized to afford 6b as a white solid. NMR (400 MHz, CD3OD/CD3CO2D/D2O 25:5:1 ) δ 0.80 (6H, t, J = 6.6, (CH2)ι2CH3), 1.11 (3H, d, J = 4.9, Me-thr), 1.13 (3H, d, J = 5.9, H-6), 1.19 (4 OH, s, (CH2)10CH3), 1.51 (4H, br t, J = 6.2, O2CCH2CH2(CH2)10CH3), 1.67 (1H, br t, J = 11.9, H-1 'a), 1.79 (1 H, br t, J = 12.2, H-1 'b), 2.27 (4H, t, J = 7.4, OzCCH^CH^nCH-,), 2.46-2.63 (4H, m, HO2CCH2CH2CONH), 3.30 (2H, m, H-3'), 3.56-3.63 (4H, m, H-2, 3, 4, 2'), 3.70 (1 H, br q, J = 6.5, H-5), 3.86 (1 H, dd, J = 9.3, 5.7, H-1 ), 4.02 (1 H, d, J = 15.4, OCHHCONH), 4.08 (1 H, d, J = 15.4, OCHHCONH), 4.12 (4H, br dd, J = 5.1 , 4.2, CONHCH(CH2θ2CR)2), 4.19 (1 H, d, J = 2.8, α-H-thr), 4.24 (1 H, dq, J = 6.2, 3.0, β-H- thr), 4.36 (1H, qui, J = 5.8, CONHCH(CjH2O2CR)2), HRMS calcd for NaC5oH91N3O15 (M+Na) 996.6348, found 996.6368.
Example B6: Preparation of 1-{(2S,3fl)-3,4-dihydroxy-2-monoglutaramidyl-butyr- amidyl}-N-(tetradecylaminocarbonylmethyl)-2-(α-L-fucopyranosyl)- ethane 7
According to the general deprotection procedure A 39 (56mg, 50μmol) is deprotected and filtered through the Anotop 25 membrane filter to yield 7 after lyophilization as a white solid. (NMR spectra at 23°C show rotamers, several peaks are doubled or broadened.) 'H NMR (400 MHz, D2O) δ 0.85 (3H, br s, (CH2)13CH3), 1.25 (25H, br s, H-6, (CH^nCHa), 1.48 (2H, br s, CONHCHzCtb), 1.86-2.32 (8h, br m, HO2C(CH2)3CONH, H-1'), 3.16-4.18 (15H, br m, H-1 , 2, 3, 4, 5, 2', α, β, γ-H-hthr, NCH2CONHCH2); 13C NMR (100 MHz, CDCI3) α 16.34, 18.51 , 23.70, 25.13, 29.54, 31.48, 32.02, 32.48, 34.48, 37.03, 42.06, 49.10, 52.47, 64.73, 69.72, 69.98, 72.46, 74.22, 74.32, 75.97, 172.07, 175.17, 177.81 , 179.36/180.13; HRMS calcd for CsC33H6ιN3On (M+Cs) 808.3360, found 808.3368.
Example B7: Preparation of compound 8
According to the general deprotection procedure A 47 (56mg, 50μmol) is deprotected and filtered through the Anotop 25 membrane filter to yield 8.
Example B8: Preparation of compound 58
To a suspension of 54 (31 mg, O.Oδmmol) in DMF (2.5ml) and Et3N (0.26ml) is added 57 (24mg, 0.05 mmol) at 0°C. The mixture is stirred for 30 min. at 0°C and 48h at RT. The solvent is removed in vacuo and the residue is dissolved in AcOEt (20ml) and washed with water. The organic layer is dried over MgSO and evaporated in vacuo. The residue is purified by gel-filtration on a Sephadex LH-20 column eluting with CHCI3: MeOH (1.1) to obtain 58. *H NMR (500 MHz, CDCI3) δ 8.37 (br, 1H), 7.94 (br, 1H), 7.51 (br, 1H), 6.63 (br, 1H), 4.94 (br, 1 H), 4.65-4.53 (m, 3H), 3.89-3.43 (m, 23H), 2.36 (br. 4H), 2.24 (t, J = 7.0 Hz, 4H), 2.18 (t, J = 7.5 Hz, 2H), 1.92 (br, 2H), 1.59 (br, 2H), 1.54-1.47 (m, 4H), 1.36-1.11 (m, 26 H), 0.88 (t, J = 6.5 Hz, 3H); 13C NMR (125 MHz, CDCI3) δ 177.1 , 1.74.1 , 174.0, 172.5, 169.8, 77.6, 77.4, 70.2, 69.8, 65.3, 65.2, 39.1 , 36.5, 31.9, 29.6, 29.5, 29.3, 29.2, 29.1 , 29.0, 28.8, 28.8, 28.3, 25.7, 22.7, 19.2, 16.2, 14.7, 14.1 ; MS m/e calcd for C52H9oN4Oi6Cs (M+Cs+): 1159.5406, found 1159.5438.
Example B9: Preparation of 6(14)
1.2 mmol (270mg) of aldehyde 5(14) are dissolved in DHAP (1mmol, 3.2ml of a 314 mM solution). The pH is adjusted to 6.8 by adding NaOH and 400 u of FDP aldolase (Sigma) are added. After overnight period the pH is adjusted to 7.5 and 1g of BaCI2 • 2 H2O (4.4 mmol) in 5 ml of water is added slowly. The cloudy mixture is kept in an ice bath for 15 min. and the precipitates are removed by centrifugation. To the supernatant 2 volumes of acetone are added and the mixture is stored at 0°C for 1 h. The precipitates are collected by centrifugation and the supernatant is discarded. The pellet is treated with Dowex-50 H* until
the solid is completely dissolved, and the resin is filtered off. The pH of the filtrate is adjusted to 7.0 by adding NaOH. Lyophilization yields the C-glycosyl phosphate 6(14) as sodium salt.
Example B9': Preparation of 4a(3)
According to Example B9 4a(3) is prepared: Η NMR (D2O, 400 MHz) δ 4.55 (dd, J=18.7, 6 Hz, 1 H), 4.45 (dd, J=18.7, 6, 1H), 4.33 (d, J=2 Hz, 1 H), 4.28 (ddd, J=10.4, 3, 2 Hz, 1 H), 4.20 (ddd, J=11.5, 3.6, 2 Hz, 1H), 3.77 (dd, J=3.3, 9.3 Hz, 1 H), 3.74 (dd, J=12.1 , 5.8 Hz, 1H), 3.67 (dd, J=9.3, 3.3 Hz, 1 H), 3.56 (dd, J=12.1 , 5.8 Hz, 1 H), 3.48 (t,J=9.3 Hz, 1H), 3.42 (ddd, J=9.3, 5.8, 2.2 Hz, 1H), 1.92 (ddd,J=14.7, 11.5, 3 Hz,1 H), 1.60 (ddd, J=14.7, 10.4, 3.6 Hz, 1 H) ppm;,3C NMR (D2O,100 MHz), δ 212.60, 78.13, 75.1 1 , 73.97, 72.09, 70.86, 68.40, 68.20, 67.65, 61.47, 30.49 ppm.
Example B10: Preparation of Compound 7(14)
Starting from 5(14) and C-DHAP [Fessner et al. Angew. Chem. Int. Ed. Eng. 33:209 (1994); Arth et al. Liebigs Ann., 2037 (1995)] (1mmol, 3ml of a 330 mM solution) 7(14) is prepared in analogy to Example B9.
Example B11: Preparation of Compound 13(14)
Starting from 12(14) and DHAP 13(14) is prepared in analogy to Example B9.
Example B12: Preparation of (2S,3fl)-N-carboxylmethyl-2,3-dihydroxy-4-(α-D-manno- pyranosyl)-butyramide 5(15)
An ice-cold solution of LiOH (20 ml, 0.25 M in MeOH/H2O 3:1 ) is added to 13(15) (ethyl (2S,3/7)-2,3-dihydroxy-4-(tetra-O-benzyl-α-D-mannopyranosyl)-butanoate) prepared from 2- (tetra-O-benzyl-α-D-mannopyranosyl)acetaldehyde according to Blanchette et al. [Tetrahedron Lett. 2183 (1984)] (1 mmol) at 0°C and vigorous stirring is continued for 2 days at 4°C. The reaction mixture is acidified with cold 1 N HCI to pH 1-2 and quickly extracted with EtOAc, washed with brine and dried over MgSO . The solvent is removed in vacuo to give the pure acid (A) as a slightly yellow oil.
According to the general procedure B for peptide coupling, the above carboxylic acid (50 mg, 78 μmol) and H-Gly-OBn • p-TsOH (30 mg, 89 μmol) are treated with EDC (18 mg, 94 μmol), HOBt (12 mg, 92 μmol) and NMM (9.5 ml, 86 μmol) in DCM (0.9 ml) for 6 h to obtain the desired amide (53 mg, 86%) as a pale yellow oil.
According to the general procedure A for hydrogenation of benzyl ethers, the above penta- benzyl compound (52.5 mg, 66.5 μmol) is deprotected and subsequently filtered through the Anotop 10 (0.02 μm) filter to yield polyhydroxyl compound 5(15) after lyophilization as a white solid. 1H NMR (400 MHz, D2O) δ 1.70 (1H, ddd, J = 14.2, 10.4, 3.1 , H-1'a), 2.08 (1 H, m, H-1 'b), 3.53 (1H, ddd, J = 9.4, 6.0, 1.6, H-5), 3.64 (1H, t, J = 9.4, H-4), 3.71 (1H, dd, J = 12.1 , 6.3, H-6a), 3.80 (1 H, dd, J = 9.3, 3.2, H-3), 3.86 (1H, dd, J = 12.2, 1.9, H-6b), 3.90 (1 H, dd, J = 2.9, 1.7, H-2), 3.94 (1 H, d, J = 17.9 gly-Ha), 4.04 (1 H, d, J = 17.8, gly-Hb), 4.06-
4.15 (2H, m, H-1 , 2"), 4.16 (1 H, d, J = 2.6, H-3'); ,3C NMR (100 MHz, D2O) δ 33.05, 44.7 (br), 63.75, 69.84, 70.68, 73.17, 74.34, 76.17, 76.78, 77.29, 175.7 (br), 177.61 ; ESI MS catcd for C12H2ιNO10 (M) 339, found (pos.: M+H+) 340, (neg.: [M-H]') 338.
Example B13: Preparation of (2S,3fl)-N-(benzyl-L-phenylalaninyl)-2,3-dihydroxy-4-(α- D-mannopyranosyl)-butyramide 6(15)
Starting from carboxylic acid A (51 mg, 79 μmol) and H-Phe-OBn-HCI (26 mg, 89 μmol) compound 6(15) is prepared in analogy with Example B12. *H NMR (500 MHz, D2O) δ 1.47 (1 H, br t, J = 11.5, H-1 'a), 1.89 (1 H, br t, J = 12.9, H-1 "b), 3.02 (1 H, br s, β-Ha-phe), 3.13 (1H, br d, J = 10.8, β-Hb-phe), 3.40 (1 H, dd, J = 7.3, 7.0), 3.54 (1H, t, J = 9.3), 3.62, (1 H, dd, J= 11.7, 5.9), 3.68 (1 H, br d, J = 7.0), 3.76 (1 H, d, J = 11.3), 3.77 (1 H, m), 3.93 (1 H, br d, J = 7.7), 4.01 (1H, d, J = 11.1), 4.00-4.03 (1 H, m), 4.54 (1 H, br s), 7.19-7.29 (5H, m, aromatic); 13C NMR (100 MHz, CDCI3) δ 31.17, 37.63, 62.09, 68.20, 68.86, 71.50, 72.64, 74.87, 75.58, 127.85, 129.46, 130.14, 137.57, 174.94 (br); HRMS calcd for NaC,9H27NO10 (M+Na) 452.1533, found 452.1545.
Example B14: Preparation of compound 19(15)
To a solution of 18(15) (81 mg, 0.089 mmol) in 80% HOAc/water is added a catalytic amount of Pd/C (Degussa type, 10% by wt). The solution is flushed with hydrogen for 30
min then stirred for 24 h under a H2 atmosphere. The reaction mixture is filtered through Celite and evaporated down under reduced pressure. The crude oil is further evaporated with H2O (2 x 5 ml) and finally lyophilized giving 19(15) as a white hygroscopic solid: 1 H NMR (D2O, 400 MHz) δ 4.56-4.55 (m, 2 H), 4.40-4.30 (m, 1 H), 4.50-3.55 (m, 13 H), 3.52 (s, 3 H), 2.83 (dd, J = 9.8, 15.8 Hz, 1 H), 2.61 (dd, J = 5.2, 15.7 Hz, 1 H); electrospray MS calcd for C,7H28O8N (M - H), 454, found 454.
Example B15: Preparation of compound 24(15)
To a solution of 23(15) (33 mg, 0.037 mmol) in 80% HOAc/water (10 ml) is added a catalytic amount of Pd/C (Degussa type, 10% by wt). The solution is flushed with hydrogen for 30 min then stirred for 24h under a H2 atmosphere. The reaction mixture is filtered through Celite and evaporated down under reduced pressure. The crude oil is further evaporated with water (2 x 15 ml) and finally lyophilized giving 24(15): 1H NMR (D2O, 400 MHz) δ 8.02 (d, J = 7.6 Hz, 1 H), 4.58 (s, 2 H), 4.51 (s, 1 H), 4.48 (s, 1 H), 4.24-4.16 (m, 2 H), 4.07 (s, 1 H), 3.84-3.73 (m, 6 H), 3.62 (dd, J = 3.2, 4.0 Hz, 1 H), 3.55-3.45 (m, 5 H).
Example B16: Preparation of Compound 27(15)
26(15) (61 mg, 0.169 mmol) is dissolved in 90% TFA:water (3 ml) and stirred for 4 h. The reaction mixture is evaporated down under reduced pressure and any residual TFA is removed by two co-evaporations with toluene (2 x 25 ml). The crude mimic is dissolved in water (10 ml), filtered, and lyophilized giving 27(15): HRMS calcd for C10H1BO8N (M + H), 280.1032, found 280.1038.
Example B17: Preparation of Compound 29(15)
Starting from 28(15) 29(15) is prepared in analogy to Example B16. HRMS calcd for CnH2oO8N (M + H), 294.1189, found 294.1184.
Example B20: Preparation of methyl-2-[N-(2,3,4,6-hydroxy-α-D-mannopyranoside) carbonyl]amino-3-[(2-aceticacid)oxy]-4,6-hydroxy-galactopyranoside 1(3)
Starting from a solution of 13(3) (100 mg, 0.119 mmol) in CH2CI2 (10 ml) the corresponding carboxylic acid is prepared according to Example A30(d).
To a solution of the above protected mimic (33 mg, 0.037 mmol) in 80% HOAc/H2O (10 ml) is added a catalytic amount of Pd/C (Degussa type, 10% by wt). The solution is flushed with hydrogen for 30 min then stirred for 24 h under a H2 atmosphere. The reaction mixture is filtered through Celite and evaporated down under reduced pressure. The crude oil is further evaporated with H2O (2 x 15 ml) and finally lyophilized giving 1(3): 1H NMR (D2O, 400 MHz) δ 8.02 (d, J = 7.6 Hz, 1 H), 4.58 (s, 2 H),4.51 (s, 1 H), 4.48 (s, 1 H), 4.24-4.16 (m, 2 H), 4.07 (s, 1 H), 3.84-3.73 (m, 6 H), 3.62 (dd, J = 3.2, 4.0 Hz, 1 H), 3.55-3.45 (m, 5 H).
Example B 21 : Preparation of N-[1-(6-O-hexadecanyl-α-D-mannopyranosyl)]acetyl-L- glutamic acid 3(3)
To a mixture of 17(3) (250 mg, 0.24 mmol) in HOAc THF/H2O (12 ml, 4/1/1) is added a catalytic amount of Pd/C (Degussa type, 10% by wt). The solution is flushed with hydrogen for 30 min then stirred for 24 h under a H2 atmosphere. The reaction mixture is filtered and co-evaporated with toluene under reduced pressure. The crude product is recrystallized from chloroform and hexane to yield 3(3): H NMR (400 MHz, CD3OD/CDCI3 = 1/1 ) δ 4.52- 4.48 (m, 1 H), 4.30-4.26 (m, 1 H), 3.76-3.69 (m, 6 H), 3.50 (t, J = 7.0 Hz, 2 H). 2.67 (dd, J = 14.9, 8.2 Hz, 1 H), 2.57 (dd, J = 14.9, 5.8 Hz, 1 H), 2.44-2.40 (m, 2 H), 2.26-2.22 (m, 1 H), 2.05-1.98 (m, 1 H), 1.59-1.56 (m, 2 H), 1.27 (bs, 26 H), 0.89 (t, J = 6.9 Hz, 3H); HRMS (FAB, M+Na) calcd for C29H53NO10 a 598.3567, found 598.3576.
Example B22: Preparation of 4(3) (Enzymatic aldoi reaction)
1.2-1.5 mmol of 18(3) is dissolved in a solution of DHAP, (1 mmol, 3 ml of a 330 mM solution). The pH is adjusted to 6.7 by adding NaOH and 200 u of FDP aldolase (Sigma) is added. After DHAP has been consumed (UV assay) and 31 P-NMR shows the appearance of a new product, the pH is adjusted to 8 and 1g of BaCI2 • 2 H2O (4.4 mmol) in 5 ml of water is added slowly. The cloudy mixture is kept in an ice bath for 15 min and the precipitates are removed by centrifugation. Two volumes of acetone are added to the supemate and the mixture is stored at 0CC for 1 h. The precipitates are collected by centrifugation and the supernatant is discarded. The pellet is treated with Dowex-50 H+ until the solid is completely dissolved (ca. 30min), and the resin is filtered off. The pH of the filtrate is adjusted to 7.0 by adding NaOH. Lyophilisation of the solution yields a mixture of the phosphonates that are further separated by ion exchange (HCO3-column, 400mM of Et3NH-HCO3), converted to the H+ form (Dowex-50 H+) and lyophilized to yield 4(3). 1H NMR (D2O, 400 MHz) δ 4.72 (d,
J=1.7 Hz.1H). 4.69 (dd, J=18.4, 6.7 Hz, 1 H), 4.54 (dd, J=18.4, 6.7 Hz, 1H), 4.41 (J=3 Hz, 1H), 4.15 (m, J=8.7, 5.7, 3 Hz, 1H), 3.83 (dd,J=3.3, 1.7 Hz, 1H), 3.75-3.65 (m, 3H, 3.60 (m, 2H), 3.55-3.45 (m, 2H) ppm; 13C NMR (D2O,100 MHz), δ,206.07, 96.49, 76.71 , 73.72, 71.11 , 70.94, 70.71 , 69.18, 68.04, 65.71, 61.73 ppm.
Example B23: Preparation of Compounds of Table 1(3)
Table 1 (3):
Compound 63(3) is dissolved in a mixture of THF/water (1/1) solution and hydrogenated at 1 atm in the presence of a catalytic amount of Pd/C. After stirred at RT for 6 h, the reaction mixture is filtered off using celite pad. The solvent is removed under vacuum to give free amine compound which can be used in the next step without further purification.
To a suspension of above amine in DMF (.10 M) is added OSu activated ester, RCOOSu (1.1 equivalents; R is a radical derived from the following acids; the activated ester is derived by reacting 1.1 equivalents of succinic anhydride with 1.0 equivalents of the following commercially available acids in 0.10 M methylene chloride at 0°C for 6 h: the acids are as follows: hexanoic acid, heptanoic acid, octanoic acid, nonanoic acid, decanoic acid, un- decanoic acid, lauric acid, tridecanoic acid, myristic acid, pentadecanoic acid, palmitic acid, heptadecanoic acid, stearic acid, nonadecanoic acid, eicosanoic acid, hexaicosanoic acid, docosanoic acid, tricosanoic acid, tetracosanoic acid, hexacosanoic acid, heptacosanoic acid, octacosanoic acid, triacontanoic acid, 4-phenylbutyric acid, 5-phenyl valeric acid, 6-phenyl hexanoic acid, oleic acid, 3-trans-7-trans-farnesoic acid, 8-trans-10-trans-dodecan- dien-1 -carboxylic acid, 2-naphthanoic acid, 1 -hydroxy-2-naphthanoic acid, 1 ,4-dihydroxy- 2-naphthanoic acid) at 0°C. The mixture is stirred overnight at 0°C. The solvent is removed in vacuo and the residue is dissolved in water (and washed with ether. The water layer is lyophilized to obtain compounds 39(3) to 58c(3).
Example B24: Preparation of 69(3)
To a stirred solution of 68(3) in 2 ml of HOAc are added 2 drops of H2O, a catalytic amount of 10% Pd/C and Ha gas. After stirring for 1 day, the catalyst is filtered off through a pad of celite and the pad is rinsed with HOAc. The filtrate is concentrated under reduced pressure to provide a white solid or a colorless oil. After lyophilization this product is a white hygroscopic solid 69(3).
Example B25: Preparation of 72(3)
The Boc compound 71(3) (1.0 mmol) is dissolved in a 50:50 mixture of CH2CI2:TFA and the mixture is cooled to 0°C. After 30 min, the residue is concentrated to remove the excess TFA and CH2CI2 and the residue is rinsed with CHCI3 and concentrated to remove any traces of TFA. The TFA amine salt is the one used in the general procedure for coupling a carboxylic acid and an amine, using an additional equivalent of NMM. To a stirred 0°C solution of the succinate ester of carboxylic acid RCO2Su, (1.0 mmol) (the activated ester is derived by reacting 1.1 equivalents of succinic anhydride with 1.0 equivalents of an acid in 0.10 molar methylene chloride at 0°C for 6 h: useful acids are mentioned in example B 23), HOBt (1.2 mmol), the amine (2.0 mmol) and NMM (2.5 mmol) in CH2CI2 (0.5 M) is added EDC (1.3 mmol). After stirring overnight and subsequent warming to RT sat. NaHCO3 soln. and CH2CI2 are added to the reaction mixture. The aqueous portion is extracted twice with CH2CI2. The combined organic fractions are washed with 1 N HCI and brine, dried over Na2SO4 and concentrated. The crude residue is purified by flash chromatography in silica gel using ethyl acetate/hexane as the eluent to afford compound 72(3).
Example B26: Preparation of 79(3)
To a stirred solution of the amide 78(3) in 2 ml of HOAc are added 2 drops of H2O, a catalytic amount of 10% Pd/C and H2 gas. After stirring for 1 day, the catalyst is filtered off through a pad of celite and the pad is rinsed with HOAc. The filtrate is concentrated under reduced pressure to provide a white solid or a colorless oil. After lyophilization this product is a white hygroscopic solid 79(3).
Example B29: Preparation of 3-{N-[1-(6-O-Hexadecanyl-α-D-mannopyranosyl)]- acetyl)aminobenzoic acid 3a(3)
The preparation from 83a(3) is followed by the procedure according to Example B27 to afford 3a(3).
1H NMR (400 MHz, CD3OD/CDCI3 = 1/1 ) δ 8.16 (s, 1H), 7.87 (d, J = 7.6 Hz, 1 H), 7.78 (d, J = 7.6 Hz, 1 H), 7.40 (t, J = 7.6 Hz, 1 H), 4.39-4.36 (m, 1 H), 4.10 (s, 1 H), 3.82-3.64 (m, 5 H), 3.47 (t, J = 7.1 Hz, 2 H), 2.81 (dd, J = 15.1 , 9.9 Hz, 1 H), 2.67 (dd, J = 15.1 , 4.6 Hz, 1 H), 1.44-1.18 (m, 28 H), 0.89 (t, J = 6.8 Hz, 3 H); HRMS (FAB, M+Cs) calcd for C3,H53NO8Cs 698.2669, found 698.2684.
Example B30: Preparation of 102(3)
To a solution of 1021(3) (33 mg, 0.045 mmol) in 80% acetic acid/H2O is added a catalytic amount of Pd/C (Degussa type, 10% by wt; Aldrich). The solution is flushed with hydrogen for 30 min then stirred for 24 h under a H2 atmosphere. The reaction mixture is filtered and evaporated down under reduced pressure. The crude oil is further evaporated with H2O (2 x 5 ml) and finally lyophilized giving the desired glycine mimic 102(3): 1H NMR (D2O, 400 MHz) δ 4.33 (m, 1 H), 3.68-4.0 (m, 6 H), 3.64 (t, J = 3.1 Hz, 1 H), 3.50-3.60 (m, 1 H), 2.81 (dd, J = 10.0, 14.7 Hz, 1 H), 2.57 (dd, J = 4.4, 14.7 Hz, 1 H), 13C NMR (D2O/DMSO, 100 MHz) δ 175.48, 77.42, 77.02, 73.14, 72.91 , 69.56, 63.40, 37.57; HRMS calcd for C10Hι8O8N (M + H), 280.1032, found 280.1034.
Example B31 : Preparation of 103(3)
Starting from 1031(3) 103(3) is prepared according to Example B30: 1H NMR (D2O, 400 MHz) δ 7.11 (d, J = 8.44 Hz, 2 H), 6.82 (d, J = 8.1 Hz, 2 H), 4.53 (dd, J = 5.2, 8.40 Hz, 1 H), 4.21 (dd, J = 6.8, 6.8 Hz, 1 H), 3.58-3.79 ( , 5 H), 3.44-3.47 (m, 1 H), 3.12 (dd, J = 4.8, 13.9 Hz, 1 H), 2.87 (dd, J = 8.4, 14.0 Hz, 1 H), 2.70 (dd, J = 9.2, 15.2 Hz, 1 H), 2.44 (dd, J = 5.7, 15.2 H, 1 H); 13C NMR (D2O/DMSO, 100 MHz) δ 156.69, 132.96, 131.29, 117.81 , 77.40, 76.80, 73.07, 72.87, 69.37, 63.21 , 38.66, 37.44; MS calcd for d7H22O9N (M - H) 384, found 384.
Example B32: Preparation of 104(3)
Starting from 104i(3) 104(3) is prepared according to Example B30: Η NMR (D2O, 400 MHZ) δ 4.37-4.42 (m, 1 H), 4.32 (ddd, J = 1.8, 5.0, 5.0 Hz, 1 H), 3.87 (t, J = 2.9 Hz, 1 H), 3.79 (dd, J = 3.3, 9.0 Hz, 1 H), 3.71-3.77 (m, 2 H), 3.67 (dd, J = 9.2, 9.2 Hz, 1 H), 3.53-3.60 (m, 1 H), 2.80 (dd, J = 10.8, 14.8 Hz, 1 H), 2.55 (dd, J = 5.1 , 14.9 Hz, 1 H), 2.46 (dd, J = 7.0, 7.0 Hz, 2H), 2.11-2.20 (m, 1 H), 1.90-2.02 (m, 1 H); 13C NMR (D2O/DMSO, 100 MHz) δ 192, 187, 181.8, 84.2, 83.7, 79.9, 76.2, 70.0, 44.3, 35.1 ; HRMS calcd for C,3H22O10N (M + H), 352.1244, found 352.1238.
Example B33: Preparation of (2S,3fl)-N-carboxylmethyl-2,3-dihydroxy-4-(α-D-manno- pyranosyl)-butyramide 105(3)
An ice-cold solution of LiOH (20 ml, 0.25 M in MeOH/H2O 3:1 ) is added to ethyl ester 113(3) (1 mmol) at 0°C and vigorous stirring is continued for 2 days at 4°C. The reaction mixture is acidified with cold 1 N HCI to pH 1-2 and quickly extracted with EtOAc, washed with brine and dried over MgSO4. The solvent is removed in vacuo to give the pure acid (A) as a slightly yellow oil.
According to the general procedure B for peptide coupling, the above carboxylic acid (50 mg, 78 μmol) and H-Gly-OBn • p-TsOH (30 mg, 89 μmol) are treated with EDC (18 mg, 94 μmol), HOBt (12 mg, 92 μmol) and NMM (9.5 μl, 86 μmol) in DCM (0.9 ml) for 6 h to obtain the desired amide.
According to the general procedure A for hydrogenation of benzyl ethers, the above penta- benzyl compound (52.5 mg, 66.5 μmol) is deprotected and subsequently filtered through the Anotop 10 (0.02 μm) filter to yield polyhydroxyl compound 105(3) after lyophilization. Η NMR (400 MHz, D2O) δ 1.70 (1 H, ddd, J = 14.2, 10.4, 3.1 , H-1 'a), 2.08 (1 H, m, H-1'b), 3.53 (1H, ddd, J = 9.4, 6.0, 1.6, H-5), 3.64 (1H, t, J = 9.4, H-4), 3.71 (1 H, dd, J = 12.1 , 6.3, H-6a), 3.80 (1H, dd, J, = 9.3, 3.2, H-3), 3.86 (1H, dd, J = 12.2, 1.9, H-6b), 3.90 (1H, dd, J = 2.9, 1.7, H-2), 3.94 (1H, d, J = 17.9 gly-Ha), 4.04 (1H, d, J = 17.8, gly-Hb), 4.06-4.15 (2H, m, H-1, 2'), 4.16 (1H, d, J = 2.6, H-3'); 13C NMR (100 MHz, D2O) δ 33.05, 44.7 (br), 63.75, 69.84, 70.68, 73.17, 74.34, 76.17, 76.78, 77.29, 175.7 (br), 177.61 ; ESI MS calcd for C12H21NO10 (M) 339, found (pos.: M+H+) 340, (neg.: [M-H] ) 338.
Example B33': Preparation of(2S,3fl)-N-{benzyl-L-phenylalaninyl)-2,3-dihydroxy-4-(α- D-mannopyranosyl)-butyramide 106(3)
According to general procedure B for peptide coupling, previously prepared carboxylic acid A (51 mg, 79 μmol) and H-Phe-OBn • HCI (26 mg, 89 μmol) are treated with EDC (20 mg, 104 μmol), HOBt (14 mg, 104 mmol) and NMM (25 μl, 227 μmol) in DCM (0.9 ml) for 6 h to obtain the desired amide as a yellow oil.
According to the general procedure A for hydrogenation of benzyl groups , the above pentabenzyl compound (64 mg, 72.7 μmol) is deprotected and subsequently purified by Sephadex G 10 column filtration (H2O) to yield polyhydroxylated compound 106(3). 1H NMR (500 MHz, D2O) δ 1.47 (1 H, br t, J = 11.5, H-1'a), 1.89 (1 H, br t, J = 12.9, H-1'b), 3.02 (1H, br s, β-Ha-phe), 3.13 (1H, br d, J = 10.8, β-Hb-phe), 3.40 (1 H, dd, J = 7.3, 7.0), 3.54 (1 H, t, J = 9.3), 3.62, (1 H, dd, J = 11.7, 5.9), 3.68 (1 H, br d, J = 7.0), 3.76 (1 H, d, J = 11.3), 3.77 (1 H, m), 3.93 (1 H, br d, J = 7.7), 4.01 (1 H, d, J = 11.1 ), 4.00-4.03 (1 H, m), 4.54 (1 H, br s), 7.19-7.29 (5H, m, aromatic); 13C NMR (100 MHz, CDCI3) δ 31.17, 37.63, 62.09, 68.20, 68.86, 71.50, 72.64, 74.87, 75.58, 127.85, 129.46, 130.14, 137.57, 174.94 (br); HRMS calcd for NaC19H27NO,0 (M+Na) 452.1533, found 452.1545
Example C1 :
(a) Preparation of liposome 59: 2.56 mg (0.0025 mmole) of lipid compound 58 and 17.79 mg (0.0475 mmole) of 57 are dissolved in CHCI-3 MeOH (10:1 ) solution. The solvents are evaporated and the residue is shielded from light and dried in vacuo. 5ml of HEPES buffer (20 mM, pH = 7.4) is added to yield a heterogeneous solution. To obtain a clear homogeneous solution, the lipid/buffer mixture is then sonicated with a probe-tip sonicator for at least 1h at the maximum power setting at which no frothing occurs and at which there is minimal disturbance of the solution surface. The temperature is maintained above the gel-liquid crystal phase transition point (Tm = 64°C) with the heat generated from sonication.
(b) Polymerization of liposome precursor to form lipid polymer 60: To polymerize the liposome, the liposome solution is transferred to a petri dish resting on a bed of wet ice, cooled to 0°C, and irradiated at 254 nm for 1h with a hand-held UV lamp placed in 1 cm about the
petri dish, yielding dark-blue paramagnetic polymerized liposomes (PPL). The PPL are then filtered through a 0.2μm mesh and collected (Procedure similar to that found in J. Am. Chem. Soc. 117:7301-7306 (1995); (Tm = 37°C, yellow PPL).
Example C2:
(a) Preparation of liposome precursor to compound 62: The liposome precursor to compound 62 is prepared according to Example C1(a) starting from 2.56 mg (0.0025 mmole) of lipid compound 58 and 17.79 mg (0.0475 mmole) of 61 (Avanti Plar Lipids Inc.).
(b) Polymerization of liposome precursor to form lipid polymer 62: Lipid polymer 62 is prepared according to Example C1(b) starting from the above precursor.
Example D: Protocol for Assaying Biological Activity
A soluble form of E-selectin (sol-E-selectin) is prepared for inhibition assays of the SLex mimetics. A 1.67 kbp DNA fragment encoding a truncated structural gene for E-selectin is isolated by PCR amplification of cDNA derived from mRNA that is isolated from IL-1 activated human endothelial cells. The cDNA is subcloned into the vector pBluescript II and is transfected into 293 cells. The clones are screened for the production of sol-E-selectin, and the clone 293#3 is selected as the stable cell line that produces the greatest amount of sol-E- selectin per cell. Sol-E-selectin is produced on a large scale from this line using a Nunc cell factory. Recombinant sol-E-selectin is isolated from the media using immunoaffinity chromatography.
The SLex mimetics are assayed for ability to block the adhesion of HL-60 cells to immobilized sol-E-selectin. Immobilized E-selectin is incubated first with inhibitor and then with HL- 60 cells. The bound cells are lysed, and myeloperoxidase released from the bound cells is detected with o-phenylenediamine and hydrogen peroxide. The percentage inhibition is determined by comparing the absorbance of the resulting solution at 492 nm to that in wells containing no inhibitor.
Each data point in the E-selectin assay is a direct measure of cells bound using a quantitative enzyme assay. The values are then plotted to give the titration curve and ICso values. The procedure described herein is adopted from Wong et. al. [J. Am. Chem. Soc. 177:66- 79 (1995)]. In this assay the compounds of formula I show an inhibition at 3 mM of 70% to 80%, or an IC5o value of from 0.1 mM to 0.2 mM.