WO1990000172A1 - 5-deaza-5,7-disubstituted-aminopterin analogues - Google Patents

5-deaza-5,7-disubstituted-aminopterin analogues Download PDF

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WO1990000172A1
WO1990000172A1 PCT/US1989/002725 US8902725W WO9000172A1 WO 1990000172 A1 WO1990000172 A1 WO 1990000172A1 US 8902725 W US8902725 W US 8902725W WO 9000172 A1 WO9000172 A1 WO 9000172A1
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methyl
cyano
diamino
methoxymethoxy
ethoxycarbonyl
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PCT/US1989/002725
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French (fr)
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Kyoichi A. Watanabe
Tsann-Long Su
Jai-Tung Huang
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Sloan-Kettering Institute For Cancer Research
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    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07D—HETEROCYCLIC COMPOUNDS
    • C07D471/00—Heterocyclic compounds containing nitrogen atoms as the only ring hetero atoms in the condensed system, at least one ring being a six-membered ring with one nitrogen atom, not provided for by groups C07D451/00 - C07D463/00
    • C07D471/02—Heterocyclic compounds containing nitrogen atoms as the only ring hetero atoms in the condensed system, at least one ring being a six-membered ring with one nitrogen atom, not provided for by groups C07D451/00 - C07D463/00 in which the condensed system contains two hetero rings
    • C07D471/04—Ortho-condensed systems
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61P—SPECIFIC THERAPEUTIC ACTIVITY OF CHEMICAL COMPOUNDS OR MEDICINAL PREPARATIONS
    • A61P35/00—Antineoplastic agents
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07D—HETEROCYCLIC COMPOUNDS
    • C07D213/00—Heterocyclic compounds containing six-membered rings, not condensed with other rings, with one nitrogen atom as the only ring hetero atom and three or more double bonds between ring members or between ring members and non-ring members
    • C07D213/02—Heterocyclic compounds containing six-membered rings, not condensed with other rings, with one nitrogen atom as the only ring hetero atom and three or more double bonds between ring members or between ring members and non-ring members having three double bonds between ring members or between ring members and non-ring members
    • C07D213/04—Heterocyclic compounds containing six-membered rings, not condensed with other rings, with one nitrogen atom as the only ring hetero atom and three or more double bonds between ring members or between ring members and non-ring members having three double bonds between ring members or between ring members and non-ring members having no bond between the ring nitrogen atom and a non-ring member or having only hydrogen or carbon atoms directly attached to the ring nitrogen atom
    • C07D213/60—Heterocyclic compounds containing six-membered rings, not condensed with other rings, with one nitrogen atom as the only ring hetero atom and three or more double bonds between ring members or between ring members and non-ring members having three double bonds between ring members or between ring members and non-ring members having no bond between the ring nitrogen atom and a non-ring member or having only hydrogen or carbon atoms directly attached to the ring nitrogen atom with hetero atoms or with carbon atoms having three bonds to hetero atoms with at the most one bond to halogen, e.g. ester or nitrile radicals, directly attached to ring carbon atoms
    • C07D213/78—Carbon atoms having three bonds to hetero atoms, with at the most one bond to halogen, e.g. ester or nitrile radicals
    • C07D213/84—Nitriles
    • C07D213/85—Nitriles in position 3

Definitions

  • the antitumor agents methotrexate and aminopterin, inhibit dihydrofolate reductase to exert their antitumor activity (J.S. Erickson, et al., J. Biol. Chem., vol. 247, p. 5661, 1972).
  • Aminopterin is prepared from 2, 4, 5, 6 - tetramino pyrimidine sulfate, 2, 3-dibromopropionablehyde and paminobenzoylglutamic acid (Seeger, et al., J. Am. Chem. Soc, vol. 69, p. 2567, 1947) or from 6-(bromomethyl)2,4-diaminopteridine HBr (Piper, Montgomery, J. Heterocycl. Chem., vol. 11, p. 279, 1974). Methotrexate preparation is described in Seeger, et al., J. Am. Chem. Soc, vol. 71, p. 1753, 1949.
  • the present invention provides a method for syntheis of 5-deaza-7-substituted and 5- deaza-5, 7-disubstituted analogues of methotrexate and aminopterin.
  • the analogues of the present invention can not be metabolized to their corresponding 7-oxo derivatives since the 7 position of these molecules is already substituted.
  • These analogues are also found not to inhibit dihydrofolate reductase, yet some of them exhibit potent antitumor activity.
  • the present application describes derivatives of methotrexate and aminopterin which are useful as antitumor agents, methods of synthesizing such derivatives and the biological application derivatives.
  • the derivatives of the present invention are particularly useful for treating tumors resistant to methotrexate or aminopterin because of large production of dihydrofolate reductase.
  • R 5 is a hydrogen atom, lower alkyl group of 1 - 4 carbon atoms or a phenyl group
  • R 7 is a lower alkyl group of 1 - 4 carbon atoms or a phenyl group
  • R 10 is a hydrogen atom, a methyl group or a ethyl group.
  • the invention also concerns methods of synthesizing the compounds, and precursors and intermediates useful in the manufacture of the compounds.
  • the invention further provides pharmaceutical compositions, methods of killing tumor cells, and methods of treating a subject having a tumor which comprises the use of the compounds described hereinabove.
  • the present invention concerns 7-monosubstituted and 5, 7-disubstituted-5-deazaaminopterin and 5-deazamethotrexate derivatives of the formula I.
  • Compound of general formula I may be obtained by the synthetic route which begins with condensation of cyanothioacetamide with 4-substituted alkyl 2- alkoxymethylene-3-oxopropanoates of formula II or 3- carbalkoxypropane-1, 3-diones of formula III to give the substitued 2-thiopyxidine derivatives of general IV or V, respectively:
  • R 5 and R 7 are the same or different and are lower alkyl groups of 1 -4 carbon atoms or phenyl groups (Ph) and R is a methyl (Me) or ethyl
  • the reaction is carried out in alcohol such as methanol, ethanol or propanol, in the presence of corresponding alkoxide of alkali metal, such as lithium, sodium or potassium, or organic base such as N, N-dimethylaminoethanol, 4-dimethylaminopyridine, 1, 8-diazabicyclo [5,4,0] undec-7-ene (DBU), 1,5- diazabicyclo[4,3,0]non-5-ene (DBN) or piperidine, at temperature range of from 25 oC to 97 oC (boiling poin of propanol) for aperiod of from 10 minutes to 2 days.
  • alkali metal such as lithium, sodium or potassium
  • organic base such as N, N-dimethylaminoethanol, 4-dimethylaminopyridine, 1, 8-diazabicyclo [5,4,0] undec-7-ene (DBU), 1,5- diazabicyclo[4,3,0]non-5-ene (DBN) or pipe
  • an oxidizing agent such as sodium hypochlorate, hydrogen peroxide or m-chloroperbenzoic acid, preferably mchloroperbenzoic acid
  • an inert solvent such as a chlorinated hydrocarbon or alcohol, perferably ethanol
  • the condensation reaction can be done either by treatment of the sulfones of formulae XII and XIII with free guanidine in refluxing alcohols, such as methanol, ethanol or propanol and the like, or by heating a mixture of the sulfone and guanidine carbonate in a high boiling inert solvent, such as diglyme or diphenyl ether, at a tempterature from 160 oC to 210 oC for a period of 2 to 8 hours.
  • a high boiling inert solvent such as diglyme or diphenyl ether
  • Deprotection of compounds of formulae XIV and XV to the corresponding 6-hydroxymethylpyrido[2,3-d]pyrimidines XVI and XVII can be achieved by treatment of XIV and XV with concentrated hydrochloric acid in alcohol at reflux temperature for a period of from 2 to 6 hours, or with a Lewis acid, such as boron trichloride, in an inert solvent such as chlorinated hydrocarbon, preferably methlene chloride, at a temperature range of from -78 oC to 25 oC for a period of from 2 to 24 hours.
  • a Lewis acid such as boron trichloride
  • 6-hydroxymethyl derivatives of formulae XVI and XVII are converted into the corresponding 6-bromomethyl derivatives of general formulae XVIII and XIX by treatment with a brominating agent, preferably hydrogen bromide in dioxan.
  • a brominating agent preferably hydrogen bromide in dioxan.
  • a mixture of cyanothioacetamide (54 g, 0.54 mol), 3-ethoxycarbonyl-1-phenylpropane-1,3-dione (189 g, 0.81 mol) and piperidine (37 mL) in anhydrous ethanol (600 mL) is stirred at room temperature for 1 day, and then heated under reflux for another day.
  • the mixture is concentrated in vacuo, and the residue is dissolved in chloroform, washed with water, dried over sodium sulfate, concentrated in vacuo, and chromatographed on a silica gel column (10 x 50 cm) using chloroformhexane (4:1 v/v) as the eluent.
  • diethyl (p-aminobenzoyl)-L-glutamate (3.22 g, 10 mmol)
  • diethyl (p-aminobenzoyl)-L-glutamate 3.22 g, 10 mmol
  • the residue is triturated thoroughly with warm chloroform to remove unreacted diethyl (paminobenzoyl)-L-glutamate.
  • N-p(p-[[(2,4-diamino-5,7- dimethylpyrido[2.3-d]pyrimidin-6-y1)methyl]amino]- benzoyl]-L-glutamic acid precipitates as microcrystals is collected by filtration, washed with cold water, acetone and diethyl ether, and dried in vacuo over phosphorus pentoxide, (588 mg, 42%), mp 226-227oC.
  • HL-60 cells (1.5 x 10 /mL) are grown in RPMI 1640 medi containing 10% fetal calf serum, 100 ⁇ g/mL streptomycin 100U/mL penicillin, in humidified 5% CO 2 at 37oC. Five concentrations of each compound are added for up to 72 hours exposure. Viable cells are counted with trypan blue exclusion method.
  • ED 50 values are calculated by the median-effect equation and plot using microcomputer software. Five concentrations of each compound are used for each ED 50 determination.
  • the ID 50 values of representative 5-deaza-5,7-disubstituted aminopterin analogues for cell growth inhibition in vitro are listed in Table 1. It is interesting to note that the 7-methyl and 5,7-dimethyl analogues exhibited cell growth inhibition which approached that of methotrexate during 72 hours of exposure, though they cannot be metabolized to their corresponding 7-oxo derivatives, are extremely weak inhibitors of dihydrofolate reductase, and are 1, 200-fold less potent than methotrexate in inhibiting [6- 3 H]dUrd incorporation into DNA (Table 2). These compounds show little dose-effct relationship in which a large increase in inhibitor concentration produces only a small increase in cell growth inhibition (Table 2), but they show time-dependent cytotoxicity in inhibiting leukemic cell growth.

Abstract

This invention relates to the compound having structure (I), wherein R5 is a hydrogen atom, a lower alkyl group of 1-4 carbons or a phenyl group, R7 is a lower alkyl group of 1-4 carbons or a phenyl group, and R10 is a hydrogen atom, a methyl group or an ethyl group. The invention also relates to methods and intermediates involed in synthesizing the compound, pharmaceutical composition of the compound and use of the compound to kill tumor cells and treat subjects.

Description

5-DEAZA-5, 7-DISUBSTITUTED-AMINOPTERIN ANALOGUES
The invention described herein was made in the course of work under Grant No. CA-18856 from the National Cancer Institute. The U.S. Government has certain rights in this invention.
Background of the Invention:
The antitumor agents, methotrexate and aminopterin, inhibit dihydrofolate reductase to exert their antitumor activity (J.S. Erickson, et al., J. Biol. Chem., vol. 247, p. 5661, 1972).
Figure imgf000003_0001
Aminopterin is prepared from 2, 4, 5, 6 - tetramino pyrimidine sulfate, 2, 3-dibromopropionablehyde and paminobenzoylglutamic acid (Seeger, et al., J. Am. Chem. Soc, vol. 69, p. 2567, 1947) or from 6-(bromomethyl)2,4-diaminopteridine HBr (Piper, Montgomery, J. Heterocycl. Chem., vol. 11, p. 279, 1974). Methotrexate preparation is described in Seeger, et al., J. Am. Chem. Soc, vol. 71, p. 1753, 1949. These antitumor agents are metabolized to their corresponding 7-oxo derivatives. The present invention provides a method for syntheis of 5-deaza-7-substituted and 5- deaza-5, 7-disubstituted analogues of methotrexate and aminopterin. The analogues of the present invention can not be metabolized to their corresponding 7-oxo derivatives since the 7 position of these molecules is already substituted. These analogues are also found not to inhibit dihydrofolate reductase, yet some of them exhibit potent antitumor activity. The present application describes derivatives of methotrexate and aminopterin which are useful as antitumor agents, methods of synthesizing such derivatives and the biological application derivatives. The derivatives of the present invention are particularly useful for treating tumors resistant to methotrexate or aminopterin because of large production of dihydrofolate reductase.
Summary of the Invention;
Compounds of the present invention can be represented by the formula:
Figure imgf000005_0001
wherein R5 is a hydrogen atom, lower alkyl group of 1 - 4 carbon atoms or a phenyl group, R7 is a lower alkyl group of 1 - 4 carbon atoms or a phenyl group, and R10 is a hydrogen atom, a methyl group or a ethyl group.
The invention also concerns methods of synthesizing the compounds, and precursors and intermediates useful in the manufacture of the compounds. The invention further provides pharmaceutical compositions, methods of killing tumor cells, and methods of treating a subject having a tumor which comprises the use of the compounds described hereinabove.
Description of the Invention:
The present invention concerns 7-monosubstituted and 5, 7-disubstituted-5-deazaaminopterin and 5-deazamethotrexate derivatives of the formula I.
Compound of general formula I may be obtained by the synthetic route which begins with condensation of cyanothioacetamide with 4-substituted alkyl 2- alkoxymethylene-3-oxopropanoates of formula II or 3- carbalkoxypropane-1, 3-diones of formula III to give the substitued 2-thiopyxidine derivatives of general IV or V, respectively:
Figure imgf000006_0001
wherein R5 and R7 are the same or different and are lower alkyl groups of 1 -4 carbon atoms or phenyl groups (Ph) and R is a methyl (Me) or ethyl
(Et) group.
The reaction is carried out in alcohol such as methanol, ethanol or propanol, in the presence of corresponding alkoxide of alkali metal, such as lithium, sodium or potassium, or organic base such as N, N-dimethylaminoethanol, 4-dimethylaminopyridine, 1, 8-diazabicyclo [5,4,0] undec-7-ene (DBU), 1,5- diazabicyclo[4,3,0]non-5-ene (DBN) or piperidine, at temperature range of from 25 ºC to 97 ºC (boiling poin of propanol) for aperiod of from 10 minutes to 2 days.
Alkylation of IV and V with Mel, Etl, Me2SO4 or Et-SO. gives in a polar solvent such as N,N-dimethylformamide or water in the presence of potassium carbonate at room temperature for a period of from 2 to 8 hours, the corresponding 2-alkyl-mercaptopyridines of formulae VI and VII wherein R2 is Me or Et: R, R5 and R7 are as defined above.
Figure imgf000007_0001
Compounds of formulae VI and VII are then reduced to the corresponding 5-hydroxymethylpyridines of formulae VIII and IX with a reducing agent, preferably lithium aluminum hydride, in an inert solvent, preferably diethyl ether, at a temperature range of from -78 º C to 25 ºC for a period of from 1 to 8 hours.
The hydroxy group of pyridines of formulae VIII and IX are protected to intermediates of formulae X and XI, wherein R' is MeOCH2 or PhCH2OCH2 respectively, by treatment with chloromethyl methyl ether or chloromethyl benzyl ether, preferably chloromethyl methyl ether, in an inert solvent such as chlorinated hydrocarbon, preferably chlorofrom in the presence of base described above, preferably 4- dimethylaminopyridine, at a temperature range from -5 ºC to 50 ºC for a period of from 1 to 10 hours.
Figure imgf000008_0001
Oxidation of compounds of formulae X and XI with an oxidizing agent, such as sodium hypochlorate, hydrogen peroxide or m-chloroperbenzoic acid, preferably mchloroperbenzoic acid, in an inert solvent, such as a chlorinated hydrocarbon or alcohol, perferably ethanol, at room temperature for a period from 30 minutes to 2 hours affords their corresponding sulfones of formulae of XII and XIII.
Condensation of the sulfones of the formulae XII and XIII with guanidine gives the 2, 4-diamino-7- substituted-pyrido[2,3-d]-pyrimidine XIV and and 2,4- diamino-5,7-disubstituted-pyrido[2,3-d]-pyrimidine XV, respectively. The condensation reaction can be done either by treatment of the sulfones of formulae XII and XIII with free guanidine in refluxing alcohols, such as methanol, ethanol or propanol and the like, or by heating a mixture of the sulfone and guanidine carbonate in a high boiling inert solvent, such as diglyme or diphenyl ether, at a tempterature from 160 ºC to 210 ºC for a period of 2 to 8 hours.
Figure imgf000009_0001
Figure imgf000009_0002
XIV R'=OCH2OMe or OCH2OPh XV R/=OCH2OMe or OCH2OCH2PH XVI R'=OH XVII R' =OH
XVIII R' = Br XIX R' - Br
Deprotection of compounds of formulae XIV and XV to the corresponding 6-hydroxymethylpyrido[2,3-d]pyrimidines XVI and XVII can be achieved by treatment of XIV and XV with concentrated hydrochloric acid in alcohol at reflux temperature for a period of from 2 to 6 hours, or with a Lewis acid, such as boron trichloride, in an inert solvent such as chlorinated hydrocarbon, preferably methlene chloride, at a temperature range of from -78 ºC to 25 ºC for a period of from 2 to 24 hours.
The 6-hydroxymethyl derivatives of formulae XVI and XVII are converted into the corresponding 6-bromomethyl derivatives of general formulae XVIII and XIX by treatment with a brominating agent, preferably hydrogen bromide in dioxan.
Condensation of XVIII and XIX with diethyl (paminobenzoyl)-L-glutamate followed by saponification gives the products of general formula I.
The following examples are illustrative of the process and products of the present invention, but are not to be construed as limiting. EXAMPLE 1
A mixture of cyanothioacetamide (10.0 g, 0.1 mol), ethyl 2-ethoxymethyleneacetoacetate (22.3 g, 0.12 mol) and DBU (4mL) in anhydrous ethanol (200mL) is heated at 60 ºC for 1 hurs, then cooled in an ice-bath. The solid precipitates are collected by filtration. The solid is extracted with boiling chloroform (6 x 200 mL). The chloroform extracts are concentrated in vacuo, and the residue is crystallized from chloroformethanol to give 3-cyano-5-(ethoxycarbonyl)-6-methylpyridine-2(1H)-thione (9.10 g, 41%), mp 232-233 ºC, IR (KBr) 2230-1 (CN), 1H NMR (CDC13) 61.41 (3H, t, CH2Me), 2.68 (3H, s, 6-Me), 4.38 (2H, q, CH2Me), 8.30 (1H, s, H-4). Analyses claculated for C10H10N2O2S: C, 54.04, H, 4.54, N, 12.60, S, 14.43 %. Found: C, 53.81, H, 4.75, N, 12,73, S, 14.25 %.
By following the same procedure but using the corresponding 4-substituted ethyl 2-ethyoxymethylene-3-oxo-propanoates or 3-ethoxycarbonylpropane-1 , 3-diones insteated of 2-ethyoxymethylene-acetoacetate, the following 2-thiopyridines are obtained:
3-cyano-5-(ethoxycarbonyl)-6-ethoxymethylpyridine- 2(lH)-thione,
3-cyano-5- (ethoxycarbonyl)-6-ethylpyridine-2(1H)- thione,
3-cyano-5- (ethoxycarbonyl)-6-propylpyridine-2(1H)- thione
3-cyano-5- (ethoxycarbonyl)-6-phenylpyridine-2(1H)- thione
3-cyano-5- (ethoxycarbonyl)-6-(2-fluorophenyl)pyridine- 2(1H)-thione. 3-cyano-5-(ethoxycarbonyl)-6-(4-nitrophenyl)pyridine- 2(1H)-thione,
3-cyano-5-(ethoxycarbonyl)-6-(4-methylphenyl)pyridine- 2(1H)-thione,
3-cyano-5-(ethoxycarbonyl)-6-(3-methylphenyl)pyridine- 2(1H)-thione,
3-cyano-5-(ethoxycarbonyl)-6-(4-methylphenyl)pyridine- 2(1H)-thione,
3-cyano-5-(ethoxycarbonyl)-6-(3-methoxyphenyl)pyridine- 2(1H)-thione,
3-cyano-5-(ethoxycarbonyl)-4,6-dimethylpyridine-2(1H)- thione,
EXAMPLE 2
A mixture of cyanothioacetamide (54 g, 0.54 mol), 3-ethoxycarbonyl-1-phenylpropane-1,3-dione (189 g, 0.81 mol) and piperidine (37 mL) in anhydrous ethanol (600 mL) is stirred at room temperature for 1 day, and then heated under reflux for another day. The mixture is concentrated in vacuo, and the residue is dissolved in chloroform, washed with water, dried over sodium sulfate, concentrated in vacuo, and chromatographed on a silica gel column (10 x 50 cm) using chloroformhexane (4:1 v/v) as the eluent. 3-Cyano-5-(ethoxycarbonyl)-4-methyl-6-phenylpyridine-2(1H)-thione is eluted from the column first followed by 3-cyano-5-(ethoxy-carbonyl)-6-methyl-4-phenylpyridine-2(1H)-thione is eluted from the column first followed by 3-cyano-5-(ethoxy-carbonyl)-6-methyl-4-phenylpyridine-2(1H)-thione.
After crystallization from ethanol, 26.5 g (16.4 %) of the pure 4-methyl-6-phenyl derivative is obtained, mp 147-148 ºC, IR (KBr) 2230 cm-1 (CN), 1H NMR (CDC13) δ 0.91 (3H, t, CH2Me), 2.54 (3H, s, 4-Me), 4 .03 (2H, q, Ch2Me), 2.54 (3H, s, 4-Me), 4.03 (2H, q, CH2Me) , 7.407.62 (5H, m, Ph).
Analyses calculated for C16H14N2O2S: C, 64.41, H, 4.73, N, 9.39, S, 10.75%. Found: C, 64.34, H, 4.65, N. 9.37, S, 10.89%.
The pure 6-methyl-4-phenyl isomer (6.8 g, 4.2%) is obtained after crystallization from ethanol, mp 252-253 ºC, IR (KBr) 2230 cm-1 (CN), 2H NMR (CDC13) S 0.81 (3H, t, Ch2Me), 2.61 (3H, s, 6-Me), 3.92 (2H, q, CH2Me). 7.36-7.53 (5H, m, Ph).
Analyses calculated for C16H24N2O2S: C, 64.41, H, 4.73, N, 9.39, S, 10.75%. Found: C, 64.62, H, 4.85, N, 9.40, S, 10.71 %.
By the same procedure but using ethyl 2-ethoxymethylene-2-propanoylacetate or ethyl 2-ethoxymethylene-2-(substituted-benzoyl) acetate, the following 4,6-disubstituted-2-thiopyridine derivatives are prepared: 3-cyano-5-(ethoxycarbonyl)-6-ethyl-4-methylpyridine- 2(1H)-thione,
3-cyano-5-(ethoxycarbonyl)-4-ethyl-6-methylpyridine- 2(1H)-thione,
3-cyano-5-(ethoxycarbonyl)-4-methyl-6-propylpyridine- 2(1H)-thione,
3-cyano-5-(ethoxycarbonyl)-6-methyl-4-propylpyridine- 2(1H)-thione,
3-cyano-5-(ethoxycarbonyl)-4-(2-fluorophenyl)-6- methylpyridine-2(1H)-thione,
3-cyano-5-(ethoxycarbonyl)-6-(2-fluorophenyl)-4- methylpyridine-2(1H)-thione,
3-cyano-5-(ethoxycarbonyl)-4-methyl-6-(4-nitrophenyl)- pyridine-2(1H)-thione,
3-cyano-5-(ethoxycarbonyl)-6-methyl-4-(4-nitrophenyl)- pyridine-2(1H)-thione,
EXAMPLE 3
A mixture of 3-cyano-5-(ethoxycarbonyl)-4,6-dimethylpyridine-2(1H)-thione (11.8 g. 0.05 mol), Mel (14.2 g, 0.1 mol) and K2CO3 (14.0 g, 0.1 mol) in DMF (200 mL is stireed at room temperature for 4 hours. The mixture is then diluted with cold water (300 mL).The precipitated solid is collected by filtration, washed with water (200 mL), air-dried, and crystallized from chloroform-ethanol to afford 3-cyano-5-(ethoxycarbonyl)-4,6-dimethyl-2-methylmercaptopyridine (22.2 g, 89%), mp 61-61 ºC, IR (KBr) 2225 cm-1 (CN), 1H NMR (CDC12) 8 1.40 (3H, t, CH2Me), 2.47 (3H, s, SMe), 2.56 (3H, S, 4-Me), 2.62 (3H, s, 6-Me), 4.42 (2H, q, CH2Me).
Analyses calcutated for C12H14N2O2S: C, 57,58, H, 5.64 N, 11.19, S, 12.81%. Found: C, 57.00, H, 5.68, N, 12.47, S. 12.53%.
By following the same procedure but using the corresponding pyridine-2(1H)-thiones, the following 2-methylmercaptopyridines are prepared:
3-cyano-5-(ethoxycarbonyl)-6-methyl-2- methylmercaptopyridine,
3-cyano-5-(ethoxycarbonyl)-6-ethyl-2- methylmercaptopyridine,
3-cyano-5-(ethoxycarbonyl)-2-methylmercapto-6- propylpyridine,
3-cyano-5-(ethoxycarbonyl)-2-methylmercapto-6- phenylpyridine,
3-cyano-5-(ethoxycarbonyl)-6-(2-fluorophenyl)-2- methylmercaptopyridine,
3-cyano-5-(ethoxycarbonyl)-2-methylmercapto-6-(4- nitrophenyl)pyridine,
3-cyano-5-(ethoxycarbonyl)-2-methylmercapto-6-(4- methylphenyl)pyridine,
3-cyano-5-(ethoxycarbonyl)-2-methylmercapto-6-(3- methylphenyl)pyridine,
3-cyano-5-(ethoxycarbonyl)-2-methylmercapto-6-(4- methoxypheny)pyridine,
3-cyano-5-(ethoxycarbonyl)-2-methylmercapto-6-(3- methoxyphenyl)pyridine,
3-cyano-5-(ethoxycarbonyl)-4-ethyl-6-methyl-2- methylmercaptopyridine,
3-cyano-5-(ethoxycarbonyl)-6-ethyl-4-methyl-2- methyImercaptopyridne,
3-cyano-5-(ethoxycarbonyl)-4-methyl-2-methylmercapto-6- propylpyridine,
3-cyano-5-(ethoxycarbonyl)-6-methyl-2-methylmercapto-4- propyIpyridine,
3-cyano-5-(ethoxycarbonyl)-4-methyl-2-methylmercapto-6- phenyIpyridine,
3-cyano-5-(ethoxycarbonyl)-6-methyl-2-methylmercapto-4- phenyIpyridine,
3-cyano-5-(ethoxycarbonyl)-4-(2-fluorphenyl)-6-methyl- 2-methylmercaptopyridine,
3-cyano-5-(ethoxycarbonyl)-6-(2-fluorophenyl)-4-methyl- 2-methylmercaptopyridine,
3-cyano-5-(ethoxycarbonyl)-4-methyl-2-methylmercapto-6- (4-nitrophenyl) pyridine,
3-cyano-5-(ethoxycarbonyl)-6-methyl-2-methylmercapto-4- (4-nitrophenyl) pyridine. Example 4
To a stirred suspension of 3-cyano-5- (ethoxycarbonyl)-6-ethoxymethyl-2-methylercaptopyridine (56.0 g, 0.2 mol) in dry ether (IL) is added portionwise lithium aluminum hydride (9.1 g, 0.24 mol at -15 to -10 ºC for 3 hours, and then excess lithium aluminum hydride is destroyed with IN hydrochloric acid to about pH 3. Cold water (500mL) is added tothe mixture and the ethereal layer is separated. The aqueous layer is extracted with ethyl acetate (3 x 300 mL). The combined organic solutions are washed with water, dried over sodium sulfate, concentrated, and the residue is chromatographed on a silica gel column ( 8 x 50 cm) with chloroform as the eluent which eluted unreacted starting material. The column is then washed with chloroform-methanol (50:1 v/v) to elute 3-cyano-6-ethoxymethyl-5-hydroxymethyl-2-methylmercaptopyridine which is obtained as colorless crystals after crystallization from ethanol (21.4 g, 45%), mp 67-69 ºC, IR (KBr) 2225 cm-1 (CN) , 1H NMR (CDC12) δ 1.23 (3H, t, CH2Me), 2.63 (3H, s, SMe), 3.03 (1H, brs, OH), 3.64 (2H, q, CH2Me), 4.65 (2H, S, CH3), 4.74 (2H, s, CH2), 7.83 (1H, s, H-4).
Analyses calculated for C11H14N2O2S: C, 55.44, H, 5.92, N. 11.76, S, 13.46%. Found C, 55.24, H, 5.79, N. 11.60, S, 13.21 %.
By following the same procedure but using the corresponding 5-(ethoxycarbonyl) pyridines, the following compounds are prepared:
3-cyano-5-hydroxymethyl-6-methyl-2- methylmercaptopyridine,
3-cyano-5-hydroxymethyl-6-ethyl-2- methylmercaptopyridine,
3-cyano-5-hydroxymethyl-2-methylmercapto-6- propylpyridine,
3-cyano-5-hydroxymethyl-2-methylmercapto-6- phenylpyridine,
3-cyano-5-hydroxymethyl-6-(2-fluorophenyl)-2- methylmercaptopyridine,
3-cyano-5-hydroxymethyl-2-methylmercapto-6- (4-nitrophenyl)pyridine,
3-cyano-5-hydroxymethyl-2-methylmercapto-6- (3-methylphenyl)pyridine,
3-cyano-5-hydroxymethyl-2-methylmercapto-6- (4-methylphenyl)pyridine,
3-cyano-5-hydroxymethyl-6-(3-methoxyphenyl)-2- methylmercaptopyridine,
3-cyano-5-hydroxymethyl-6-(4-methoxyphenyl)-2- methylmercaptopyridine,
3-cyano-5-hydroxymethyl-4,6-dimethyl-2- methylmercaptopyridine,
3-cyano-6-ethyl-5-hydroxymethyl-4-methyl-2- methylmercaptopyridine,
3-cyano-4-ethyl-5-hydroxymethyl-6-methyl-2- methylmercaptopyridine,
3-cyano-5-hydroxymethyl-4-methyl-2-methylmercapto-6- phenyIpyridine,
3-cyano-5-hydroxymethyl-6-methyl-2-methylmercapto-4- phenylpyridine,
3-cyano-4-(2-fluorophenyl)-5-hydroxymethyl-6-methyl-
2-methylmercaptopyridine,
3-cyano-6-(2-fluorophenyl)-5-hydroxymethyl-4-methyl- 2-methylmercaptopyridine,
3-cyano-5-hydroxymethyl-4-methyl-2-methylmercapto-6- (4-nitrophenyl)pyridine. 3-cyano-5-hydroxymethyl-6-methyl-2-methylmercapto-4- (4-nitrophenyl)pyridine,
Example 5
A solution of 3-cyano-5-hydroxymethyl-6-methyl-2-methylmercaptopyridine (44.0 g, 0.27 mol) and N,N-dimethylaniline (80.5 g, 0.54 mol) in dry chloroform (500 mL) is treated with methoxymethyl chloride (43.2 g, 0.54 mol) for 5 hours at room temperature. The mixture is washed successively with 2% hydrochloric acid (4 x 200 mL), water, and saturated sodium bicarbonate solution, then is dried over sodium sulfate and concentrated. The residue is crystallized from hexane-ether to give 3-cyano-5-(methoxymethoxy)methyl-6-methyl-2-methylmercaptopyridine (55.1 g, 84%), mp 5051ºC, 1H NMR (CDCL3) δ 2.55 (3H, s, SMe), 2.62 (3H, s, 6-Me), 3.40 (3H, s, OMe), 4.53 (2H, s, CH2), 4.71 (2H, s, CH2), 7.76 (1H, s, H-4).
Analyses calculated for C11H14N2O2S.1/4H2O: C, 55.44, H, 5.92, N, 11.76, S, 13.46%. Found: C, 55.41, 6.19, 11.54, 13.21%.
By the same procedure but using the corresponding 5-hydroxymethylpyridines, the following compounds are synthesized:
3-cyano-6-ethyl-5-(methoxymethoxy)methyl-2- methylmercaptopyridine,
3-cyano-5-(methoxymethoxy)methyl-2-methylmercapto-6- phenylpyridine,
3-cyano-5-(methoxymethoxy)methyl-2-methylmercapto-6- propylpyridine,
3-cyano-5-(2-fluorophenyl)-5-(methoxymethoxy)methyl-2- mercaptopyridine,
3-cyano-5-(methoxymethoxy)methyl-2-methylmercapto-6-(4- nitrophenyl)pyridine,
3-cyano-5-(methoxymethoxy)methyl-2-methylmercapto-6-(3- methylphenyl)pyridine,
3-cyano-5-(methoxymethoxy)methyl-2-methylmercapto-6-(4- methylphenyl)pyridine,
3-cyano-5-(methoxymethoxy)methyl-2-methylmercapto-6-(3- methoxyphenyl)pyridine,
3-cyano-5-(methoxymethoxy)methyl-2-methylmercapto-6-(4- methoxyphenyl)pyridine,
3-cyano-5-(methoxymethoxy)methyl-4,6-dimethγl-2- methylmercaptopyridine,
3-cyano-6-ethyl-5-(methoxymethoxy)methyl-4-methyl-2- methylmercaptopyridine,
3-cyano-4-ethyl-5-(methoxymethoxy)methyl-4-methyl-2- methylmercaptopyridine,
3-cyano-5-(methoxymethoxy)methyl-4-methyl-2- methylmercapto-6-phenyIpyridine,
3-cyano-5-(methoxymethoxy)methyl-6-methyl-2- methylmercapto-4-phenyIpyridine,
3-cyano-4-(2-fluorophenyl)-5-(methoxymethoxy)methyl-6- methyl-2-methylmercaptopyridine,
3-cyano-6-(2-fluorophenyl)-5-(methoxymethoxy)methyl-4- methyl-2-methylmercaptopyridine,
3-cyano-5-(methoxymethoxy)methyl-4-methyl-2- methylmercapto-6-(4-nitrophenyl)pyridine,
3-cyano-5-(methoxymethoxy)methyl-6-methyl-2- methylmercapto-4-(4-nitrophenyl)pyridine,
Example 6
A mixture of 3-cyano-5-(methoxymethoxy)methyl-2-methylmercapto-6-phenyIpyridine (69 g, 0.23 mol) and m chloroperbenzoic acid (120 g, 0.69 mol) in ethanol (60 mL) is stirred for 1 hour at room temperature, and then the solvent is removed in vacuo. The residue is redissolved in ethyl acetate (800 mL), and the solution is washed with 2% sodium hydroxide solution and water, dried over sodium sulfate, and concentrated. The residue is crystallized from ether to give 70.3 g of 3cyano-5-(methoxymethoxy)methyl-2-methylsulfonyl-6-phenylpyridine (92%), mp 101-102ºC. 1H NMR (CDC13) δ 3.39 (3H, S, Me), 4.72 (2H, S, CH2), 4.73 (2H, S, CH2), 7.55 (5H, s, Ph), 8.51 (1H, s, H-4).
Analyses calculated for C16H16N2O4S: C, 57.82, H, 4.85, N, 8.43, S, 9.65%. Found: C, 58.06, H, 5.07, N, 8.51, S, 9.81%.
By following the same procedure but using the corresponding 2-methylmercaptopyridines, the following sulfones are obtained:
3-cyano-5-(methoxymethoxy)methyl-6-methyl-2-methyl- sulfonylpyridine,
3-cyano-6-ethyl-5-(methoxymethoxy)methyl-2-methyl- sulfonylpyridine,
3-cyano-5-(methoxymethoxy)methyl-2-methylsulfonyl-6- propylpyridine,
3-cyano-6-(2-fluorophenyl)-5-(methoxymethoxy)methyl-2- methylsulfonylpyridine,
3-cyano-5-(methoxymethoxy)methyl-2-methylsulfonyl-6- (4-nitrophenyl)pyridine,
3-cyano-5-(methoxymethoxy)methyl-6-(3-methylphenyl)-2- methylsulfonylpyridine,
3-cyano-5-(methoxymethoxy)methyl-6-(4-methylphenyl)-2- methylsulfonylpyridine,
3-cyano-5-(methoxymethoxy)methyl-6-(3-methoxphenyl)-2- methyl-sulfonylpyridine, 3-cyano-5-(methoxymethoxy)methyl-6-(4-methoxyphenyl)-2- methylsulfonylpyridine,
3-cyano-5-(methoxymethoxy)methyl-4,6-dimethyl-2-methyl- sulfonylpyridine,
3-cyano-5-(methoxymethoxy)methyl-4-methyl-2-methyl- sulfonyl-6-phenylpyridine,
3-cyano-5-(methoxymethoxy)methyl-6-methyl-2-methyl- sulfonyl-4-phenyIpyridine,
3-cyano-6-ethyl-5-(methoxymethoxy)methyl-4-methyl-2- methylsulfonylpyridine,
3-cyano-4-ethyl-5-(methoxymethoxy)methyl-6-methyl-2- methylsulfonylpyridine,
3-cyano-6-(2-fluorophenyl)-5-(methoxymethoxy)methyls- methyl-2-methylsulfonylpyridine,
3-cyano-4-(2-fluorophenyl)-5-(methoxymethoxy)methyl-6- methyl-2-methylsulfonylpyridine,
3-cyano-5-(methoxymethoxy)methyl-4-methyl-2-methyl- mercapto-6-(4-nitrophenyl)pyridine,
3-cyano-5-(methoxymethoxy)methyl-6-methyl-2-methyl- sulfonyl-4-(4-nitrophenyl)pyridine.
Example 7
A mixture of 3-cyano-5-(methoxymethoxy)methyl-4-methyl2-methylsulfonyl-6-phenylpyridine (6.72 g, 20 mmol) and guanidine carbonate (3.60 g, 20 mmol) in diphenyl ether (20 mL) is heated at 180-185ºC with vigorous stirring for 2 hours. After cooling, the mixture is diluted with ethanol-diethyl ether (1:1, 200 mL). The precipitates are collected, redissolved in ethanolwater (5:1, 300 mL), decolorlized with Norit A. and the solution is concentrated to about 150 mL. Colorless crystals that deposit are collected by filtration, washed with ethanol and diethyl ether, and dried to give 2,4-diamino-6-(methoxymethoxy)methyl-5-methyl-7- phenylpyrido[2.3-d]pyrimidine (48.7 g, 75%), mp 290291ºC. 1H NMR (Me2SO-d6) δ 2.76 (3H, S, Me), 3.26 (3H, s, OMe), 4.40 (2H, s, CH2) , 4.62 (2H, s, CH2), 6.26 (2H, brs, NH2), 7.09 (2H, brs, NH2), 7.41-7.70 (5H, m, Ph) .
Analyses calculated for C17H19N5O2: C, 62.75, H, 5.89, N, 21.53%. Found: C, 62.63, H, 6.12, N, 21.56%.
By using the same procedure but using the corresponding 2-methylsulfonylpyridines, the following pyrido[2.3-d]pyrimidines are synthesized:
2,4-diamino-6-(methoxymethoxy)methyl-7-methylpyrido- [2.3-d]pyrimidine,
2,4-diamino-6-(methoxymethoxy)methyl-7-ethylpyrido- [2.3-d]pyrimidine,
2,4-diamino-6-(methoxymethoxy)methyl-7-phenylpyrido- [2.3-d]pyrimidine,
2 ,4-diamino-6-(methoxymethoxy)methyl-7-(2- fluorophenyl)pyrido[2.3-d]pyrimidine,
2,4-diamino-6-(methoxymethoxy)methyl-7--(4-nitrophenyl)- pyrido[2.3-d]pyrimidine,
2,4-diamino-6-(methoxymethoxy)methyl-7-(3- methylphenyl)pyrido[2.3-d]pyrimidine,
2,4-diamino-6-(methoxymethoxy)methyl-7-(4- methylphenyl)pyrido[2.3-d]pyrimidine,
2,4-diamino-6-(methoxymethoxy)methyl-7-(3- methoxyphenyl)pyrido[2.3-d]pyrimidine,
2,4-diamino-6-(methoxymethoxy)methyl-7-(4- methoxyphenyl)pyrido[2.3-d]pyrimidine,
2,4-diamino-6-(methoxymethoxy)methyl-5,7-dimethyl- pyrido[2.3-d]pyrimidine,
2,4-diamino-6-(methoxymethoxy)methyl-7-methyl-5-phenyl- pyrido[2.3-d]pyrimidine. 2,4-diamino-6-(methoxymethoxy)methyl-5-ethyl-7-methyl- pyrido[2.3-d]pyrimidine,
2,4-diamino-6-(methoxymethoxy)methyl-7-ethyl-5-methyl- pyrido[2.3-d]pyrimidine,
2,4-diamino-6-(methoxymethoxy)methyl-5-methyl-7-(2- fluorophenyl)pyrido[2.3-d]pyrimidine,
2,4-diamino-6-(methoxymethoxy)methyl-7-methyl-5-(2- fluorophenyl)pyrido[2.3-d]pyrimidine,
2,4-diamino-6-(methoxymethoxy)methyl-5-methyl-7-(4- nitrophenyl)pyrido[2.3-d]pyrimidine,
2,4-diamino-6-(methoxymethoxy)methyl-7-methyl-5-(4- nitrophenyl)pyrido[2.3-d]pyrimidine.
Example 8
A mixture of 2,4-diamino-6-(methoxymethoxy)methyl-7-methyl-5-phenylpyrido[2.3-d]pyrimidine monohydrate (24.0 g, 70 mmol) and concentrated hydrochloric acid (20 mL) in methanol (800 mL) is heated under reflux for 4 hours, and then concentrated in vacuo. The residue is suspended in water (300 mL) and neutralized to pH 7 with 1N sodium hydroxide solution. The solid is filtered, washed successively with water, ethanol, and diethyl ether, and dried in vacuo over phosphorus pentaoxide to give 2,4-diamino-6-hydroxymethyl-7-methyl-5-phenylpyrido[2.3-d]pyrimidine in quantitative yield. This product is sufficiently pure to be used in the next step. An analytical sample can be obtained by recrystallization of the crude product from ethanol (12.7 g, 40%), mp >300ºC. 1H NMR (Me2SO-d6) δ 2.69 (3H, s, 7-Me), 4.09 (2H, m, CH2), 5.60 (1H, brs, OH), 7.31-7.66 (5H, m, Ph), 7.40 (4H, brs, 2 x NH2).
Analyses calculated for C15H15N5O.HCl: C, 56.65, H 5.08, N, 22.04%. Found: C, 56.55, H, 5.07, N, 21.83%. By following the same procedure but using the corresponding 6-(methoxymethoxy)methylpyrido[2.3-d]pyrimidines, the following 6-hydroxymethyl derivatives are obtained:
2,4-diamino-6-hydroxymethyl-7-methylpyrido[2.3-d]- pyrimidine,
2,4-diamino-6-hydroxymethyl-7-ethylpyrido[2.3-d]- pyrimidine,
2,4-diamino-6-hydroxymethyl-7-phenylpyrido[2.3-d]- pyrimidine,
2,4-diamino-6-hydroxymethyl-7-(2-fluorophenyl)-pyrido
[2.3-d]-pyrimidine,
2,4-diamino-6-hydroxymethyl-7-(4-nitrophenyl)pyrido- [2.3-d]pyrimidine,
2,4-diamino-6-hydroxymethyl-7-(3-methylphenyl)pyrido- [2.3-d]pyrimidine,
2,4-diamino-6-hydroxymethyl-7-(4-methylphenyl)pyrido- 2.3-d]pyrimidine,
2,4-diamino-6-hydroxymethyl-7-(3-methoxyphenyl)pyrido- [2.3-d]pyrimidine,
2,4-diamino-6-hydroxymethyl-7-(4-methoxyphenyl)pyrido- [2.3-d]pyrimidine,
2,4-diamino-6-hydroxymethyl-5,7-dimethylpyrido[2.3-d]- pyrimidine,
2,4-diamino-6-hydroxymethyl-5-methyl-7-phenylpyrido- [2.3-d]pyrimidine,
2,4-diamino-6-hydroxymethyl-7-methyl-5-phenylpyrido- [2.3-d]pyrimidine,
2,4-diamino-6-hydroxymethyl-5-methyl-7-ethylpyrido- [2.3-d]pyrimidine,
2,4-diamino-6-hydroxymethyl-7-methyl-5-ethylpyrido- [2.3-d]pyrimidine,
2,4-diamino-6-hydroxymethyl-5-methyl-7-(2- fluorophenyl)pyrido[2.3-d]pyrimidine,
2, 4-diamino-6-hydroxymethyl-7-methyl-5-(2- fluorophenyl)pyrido[2.3-d]pyrimidine,
2, 4-diamino-6-hydroxymethyl-5-methyl-7-(4-nitrophenyl)-pyrido[2.3-d]pyrimidine,
2,4-diamino-6-hydroxymethyl-7-methyl-5-(4-nitrophenyl)- pyrido[2.3-d]pyrimidine.
Example 9
A suspension of 2,4-diamino-6-hydroxymethyl-7-methylpyrido[2.3-d]pyrimidine (1.05 g, 5 mmol) in dry dioxan (150 mL) is saturated with dry hydrogen bromide. The mixture is stirred overnight at room temperature, and the solvent is removed in vacuo (<35ºC). Traces of hydrogen bromide are removed azeotropically by several coevaporations with toluene, and the residue is dissolved in dry N, N-dimethylacetamide (30 mL, distilled over calcium hydride). To the solution is added diethyl (p-aminobenzoyl)-L-glutamate (3.22 g, 10 mmol), and the mixture is stirred for 3 days at room temperature. After concentration of the mixture in vacuo, the residue is triturated thoroughly with warm chloroform to remove unreacted diethyl (paminobenzoyl)-L-glutamate. The gummy residue is then solidified by trituration with diethyl ether, and the microcrystals are collected by filtration and dried in vacuo to give diethyl N-[p-[[(2,4-diamino-7-methylpyrido[2.3-d]pyrimidin-6-y1)methyl]amino]-benzoyl)-L-glutamate (2.13 g, 84%), mp 239-240 ºC, 1H
NMR (Me2SO-d6) δ 1.15 (3H, t, CH2Me), 1.18 (3H, t, CH2Me), 1.95-2.21 (2H, m, CH2), 2.25-2.45 (2H, m, CH2), 2.57 (3H, s, 7-Me), 4.03 (2H, q, CH2Me), 4.08 (2H, q, CH2Me), 4.33-4.54 (3H, brm, CH2NH, CONHCH), 6.58-6.6 (3H, brm, NH2, CH2NH), 6.66 and 7.64 (4H, ABq, Ph), 7.53-7.71 (2H, brs, NH2) , 8.31 (1H, s, H-5) .
Analyses calculated for C25H31N7O5.4H2O: C, 51.62, H, 6.75, N, 16.85%. Found: C, 51.92, H, 6.91, N, 16.54%.
By following the same procedure but using the corresponding 6-hydroxymethylpyridopyrimidines, the following protected analogues of aminopterin are synthesized: diethyl N-[p-[ (2,4-diamino-7-ethylpyrido[2.3-d]
pyrimidin-6-y1)methyl]amino]benzoyl]-L-glutamate, diethyl N-[p-[[(2,4-diamino-7-phenylpyrido[2.3-d]
pyrimidin-6-y1)methyl]amino]benzoyl]-L-glutamate, diethyl N-[p-[[(2,4-diamino-7-(2-fluorophenyl)
pyrido[2.3-d]-pyrimidin-6-y1)methyl]amino]benzoyl]- L-glutamate,
diethyl N-[p-[ (2,4-diamino-7-(4-nitrophenyl)
pyrido[2.3-d -pyrimidin-6-y1)methyl]amino]benzoyl]- L-glutamate,
diethyl N-[p-[ (2,4-diamino-7-(3-methylphenyl)
pyrido[2.3-d -pyrimidin-6-y1)methyl]amino]benzoyl]- L-glutamate,
diethyl N-[p-[ (2,4-diamino-7-(4-methylphenyl)
pyrido[2.3-d -pyrimidin-6-y1)methyl]amino]benzoyl]- L-glutamate,
diethyl N-[p-[ (2,4-diamino-7-(3-methoxyphenyl)
pyrido[2.3-d -pyrimidin-6-y1)methyl]amino]benzoyl]- L-glutamate,
diethyl N-[p-[ (2,4-diamino-7-(4-methoxyphenyl)
pyrido[2.3-d -pyrimidin-6-y1)methyl]amino]benzoyl]- L-glutamate,
diethyl N-[p-[[(2,4-diamino-5,7-dimethylpyrido
[2.3-d]-pyrimidin-6-yl)methyl]amino]benzoyl]- L-glutamate, diethyl N-[p-[[(2,4-diamino-5-methyl-7-phenylpyrido
[2.3-d]-pyrimidin-6-y1)methyl]amino]benzoyl]¬
L-glutamate,
diethyl N-[p-[[(2,4-diamino-7-methyl-5-phenylpyrido
[2.3-d]-pyrimidin-6-y1)methyl]amino]benzoyl]¬
L-glutamate,
diethyl N-[p-[[(2,4-diamino-5-methyl-7-ethylpyrido
[2.3-d]-pyrimidin-6-y1)methyl]amino]benzoyl]¬
L-glutamate,
diethyl N-[p-[[(2,4-diamino-7-methyl-5-ethylpyrido
[2.3-d]-pyrimidin-6-y1)methyl]amino]benzoyl]¬
L-glutamate,
diethyl N-[p-[[(2,4-diamino-5-methyl-7-(2-fluorophenyl) pyrido[2.3-d]-pyrimidin-6-y1)methyl]amino]benzoyl]¬
L-glutamate,
diethyl N-[p-[[(2,4-diamino-7-methyl-5-(2-fluorophenyl) pyrido[2.3-d]-pyrimidin-6-y1)methyl]amino]benzoyl]¬
L-glutamate,
diethyl N-[p-[[(2,4-diamino-5-methyl-7-(4-nitrophenyl) pyrido[2.3-d]-pyrimidin-6-y1)methyl]amino]benzoyl]¬
L-glutamate,
diethyl N-[p-[[(2,4-diamino-7-methyl-5-(4-nitrophenyl) pyrido[2.3-d]-pyrimidin-6-y1)methyl]amino]benzoyl]¬
L-glutamate,
Example 10
A solution of diethyl N-[p-[[(2,4-diamino-5,7-dimethyl pyrido[2,3-d]pyrimidin-6-y1)methyl]methyl]amino]- benzoyl]-L-glutamate (1.74 g, 3 mmol) in methanol (400 mL) containing 7 mL of 1 N sodium hydroxide is stirred for 3 days at room temperature. After concentration in vacuo to about 7 mL, the solution is neutralized with IN hydrochloric acid (7 mL). N-p(p-[[(2,4-diamino-5,7- dimethylpyrido[2.3-d]pyrimidin-6-y1)methyl]amino]- benzoyl]-L-glutamic acid precipitates as microcrystals is collected by filtration, washed with cold water, acetone and diethyl ether, and dried in vacuo over phosphorus pentoxide, (588 mg, 42%), mp 226-227ºC. 1H NMR (Me2SO-d6) δ 1.78-2.10 (2H, brm, CH2CH2CO2H), 2.32.4 (2H, brm, CH2CH2CO2H), 2.54 (3H, s, 7-Me), 2.66 (3H, s, 5-Me), 3.72-4.77 (3H, brm, CH2NH, CONHCH), 6.70 (2H, d, Ph), 7.71 (4H, d, Ph, NH2), exchangeable NH at 6.20, 7.16, 8.10 and 8.20.
Analyses calculated for C22H25N7O5: C, H, N, %. Found:
By the same procedure but using the corresponding diethyl L-glutamates, the following antifolates are obtained:
N-[p-[[(2,4-diamino-7-methylpyrido[2.3-d]pyrimidin-6- y1)methyl]amino]benzoyl]-L-glutamic acid,
N-[p-[[(2,4-diamino-7-ethylpyrido[2.3-d]pyrimidin-6- y1)methyl]amino]benzoyl]-L-glutamic acid,
N-[p-[[(2,4-diamino-7-phenylpyrido[2.3-d]pyrimidin-6- y1)methyl]amino]benzoyl]-L-glutamic acid,
N-[p-[[(2,4-diamino-7-(2-fluorophenyl)pyrido[2.3-d]
pyrimidin-6-y1)methyl]amino]benzoyl]-L-glutamic acid, N-[p-[[(2,4-diamino-7-(4-nitrophenyl)pyrido[2.3-d]
pyrimidin-6-y1)methyl]amino]benzoyl]-L-glutamic acid, N-[p-[[(2,4-diamino-7-(3-methylphenyl)pyrido[2.3-d]
pyrimidin-6-y1)methyl]amino]benzoyl]-L-glutamic acid, N-[p-[[(2,4-diamino-7-(4-methylphenyl)pyrido[2.3-d]
pyrimidin-6-y1)methyl]amino]benzoyl]-L-glutamic acid, N-[p-[[(2,4-diamino-7-(3-methoxyphenyl)pyrido[2.3-d] pyrimidin-6-y1)methyl]amino]benzoyl]-L-glutamic acid, N-[p-[[(2,4-diamino-7-(4-methoxyphenyl)pyrido[2.3-d] pyrimidin-6-y1)methyl]amino]benzoyl]-L-glutamic acid, N-[p-[[(2,4-diamino-5,7-dimethylpyrido[2.3-d] pyrimidin-6-y1)methyl]amino]benzoyl]-L-glutamic acid, N-[p-[[(2,4-diamino-5-methyl-7-phenylpyrido[2.3-d]
pyrimidin-6-y1)methyl]amino]benzoyl]-L-glutamic acid, N-[p-[[(2,4-diamino-7-methy1-5-phenylpyrido[2.3-d]
pyrimidin-6-y1)methyl]amino]benzoyl]-L-glutamic acid, N-[p-[[(2,4-diamino-5-methyl-7-ethylpyrido[2.3-d]
pyrimidin-6-y1)methyl]amino]benzoyl]-L-glutamic acid, N-[p-[[(2,4-diamino-7-methyl-5-ethylpyrido[2.3-d]
pyrimidin-6-y1)methyl]amino]benzoyl]-L-glutamic acid, N-[p"[[(2,4-diamino-5-methyl-7-(L-fluorophenyl)
pyrido[2.3-d]pyrimidin-6-y1)methyl]amino]benzoyl]- L-glutamic acid,
N-[p-[[(2,4-diamino-7-methyl-5-(2-fluorophenyl)
pyrido[2.3-d]pyrimidin-6-y1)methyl]amino]benzoyl]-
L-glutamic acid,
N-[p-[[(2,4-diamino-5-methyl-7-(4-nitrophenyl)
pyrido[2.3-d]pyrimidin-6-y1)methyl]amino]benzoyl]- L-glutamic acid,
N-[p-[[(2,4-diamino-7-methyl-5-(4-nitrophenyl)
pyrido[2.3-d]pyrimidin-6-y1)methyl]amino]benzoyl]- L-glutamic acid.
Biological Studies
HL-60 cells (1.5 x 10 /mL) are grown in RPMI 1640 medi containing 10% fetal calf serum, 100 μg/mL streptomycin 100U/mL penicillin, in humidified 5% CO2 at 37ºC. Five concentrations of each compound are added for up to 72 hours exposure. Viable cells are counted with trypan blue exclusion method.
The incorporation of [6-3H]dUrd (0.05 μM, 1 μCl/mL) into DNA in HL-60 cells at 37ºC for 30 minutes is measured by the method of Chou et al., (Mol. Pharm.. 1984, 26, 587). Cells are preincubated with the compound for 40 minutes prior to the addition of [6-3H]dUrd.
ED50 values are calculated by the median-effect equation and plot using microcomputer software. Five concentrations of each compound are used for each ED50 determination.
The ID50 values of representative 5-deaza-5,7-disubstituted aminopterin analogues for cell growth inhibition in vitro are listed in Table 1. It is interesting to note that the 7-methyl and 5,7-dimethyl analogues exhibited cell growth inhibition which approached that of methotrexate during 72 hours of exposure, though they cannot be metabolized to their corresponding 7-oxo derivatives, are extremely weak inhibitors of dihydrofolate reductase, and are 1, 200-fold less potent than methotrexate in inhibiting [6- 3H]dUrd incorporation into DNA (Table 2). These compounds show little dose-effct relationship in which a large increase in inhibitor concentration produces only a small increase in cell growth inhibition (Table 2), but they show time-dependent cytotoxicity in inhibiting leukemic cell growth.
Preliminary study shows that N-[p-[[(2,4-diamino-5,7-dimethylpyrido[2.3-d]pyrimidin-6-y1)methyl]amino]-benzoyl]-L-glutamic acid (5-deaza-5,7-dimethyl-aminopterin) produces an increase in lifespan (ILS) at maximum tolerated dose of 100 mg/kg/day x 5 (i.p.) of 71% in BDF mice inoculated i.p. with 10 L-1210 cells.
Figure imgf000030_0001
Figure imgf000031_0001

Claims

What is claimed is:
1. A compound having the structure:
Figure imgf000032_0001
wherein R5 is hydrogen atom, a lower alkyl group of 1 - 4 carbons or a phenyl group,
R7 is a lower alkyl group of 1 - 4 carbons or a phenyl group, and
R10 is a hydrogen atom, a methyl group or an ethyl group.
2. A compound of claim 1 selected from the group consisting of: diethyl N-[p [[(2,4-diamino-7-methylpyfido[2.3-d]- pyrimidin-6-y1)methyl]amino]-benzoyl]-L-glutamate, diethyl N-[p-[[(2,4-diamino-7-ethylpyrido[2.3-d]- pyrimidin-6-y1)methyl]amino]benzoyl]-L-glutamate, -diethyl N-[p-[[(2,4-diamino-7-propylpyrido[2.3-d]- pyrimidin-6-y1)methyl]amino]benzoyl]-L-glutamate, diethyl N-[p-[[(2,4-diamino-7-phenylpyrido(2.3-d]- pyrimidin-6-y1)methyl]amino]benzoyl]-L-glutamate, diethyl N-[p-[[(2,4-diamino-7-(2-fluorophenyl)pyrido- [2.3-d]pyrimidin-6-y1)methyl]amino]benzoyl]- L-glutamate,
diethyl N-[p-[[(2,4-diamino-7-(4-nitrophenyl)pyrido- [2.3-d]-pyrimidin-6-y1)methyl]amino]benzoyl]- L-glutamate,
diethyl N-[p-[[(2,4-diamino-7-(3-methylphenyl)pyrido- [2.3-d]-pyrimidin-6-y1)methyl]amino]benzoyl]- L-glutamate,
diethyl N-[p-[[(2,4-diamino-7-(4-methylphenyl)pyrido- [2.3-d)-pyrimidin-6-y1)methyl]amino]benzoyl]- L-glutamate,
diethyl N-[p-[[(2,4-iamino-7-(3-methoxyphenyl)pyrido- [2.3-d)pyrimidin-6-y1)methyl]amino]benzoyl]- L-glutamate,
diethyl N-[p-[[(2,4-diamino-7-(4-methoxyphenyl)pyrido
[2.3-d]pyrimidin-6-y1)methyl]amino]benzoyl]- L-glutamate,
diethyl N-[p-[[(2,4-diamino-5,7-dimethypyrido[2.3-d]- pyrimidin-6-y1)methyl]amino]benzoyl]-L-glutamate, diethyl N-[p-[[(2,4-diamino-5-methyl-7-phenylpyrido- [2.3-d]pyrimidin-6-y1)methyl]amino]benzoyl]- L-glutamate,
diethyl N-[p-[[(2,4-diamino-7-methyl-5-phenylpyrido- [2.3-d]-pyrimidin-6-y1)methyl]amino]benzoyl]-
L-glutamate,
diethyl N-[p-[[(2,4-diamino-5-methyl-7-ethylpyrido- [2.3-d]-pyrimidin-6-y1)methyl]amino]benzoyl]- L-glutamate,
diethyl N-[p-[[(2,4-diamino-7-methyl-5-ethylpyrido[2.3- d]-pyrimidin-6-y1)methyl]amino]benzoyl]-L-glutamate, diethyl N-[p-[[(2,4-diamino-5-methyl-7-(2- fluorophenyl)pyrido[2.3-d]pyrimidin-6-y1)- methyl]amino]benzoyl]-L-glutamate,
diethyl N-[p-[[(2,4-diamino-7-methyl-5-(2- fluorophenyl)pyrido[2.3-d]pyrimidin-6- y1)methyl]amino]benxoyl]-L-glutamate,
diethyl N-[p-[[(2,4-diamino-5-methyl-7-(4-nitrophenyl)- pyrido[2.3-d]pyrimidin-6-y1)methyl]amino]benzoyl]L-glutamate, and
diethyl N-[p-[[(2,4-diamino-7-methyl-5-(4-nitrophenyl)- pyrido[2.3-d]pyrimidin-6-y1)methyl]amino]benzoyl]- L-glutamate. 3. A compound of claim 1 selected from the group consisting of:
N-[p-[[(2,4-diamino-7-methylpyrido[2.3-d]pyrimidin-6- y1)methyl]amino]benzoyl]-L-glutamic acid,
N-[p-[[(2,4-diamino-7-ethylpyrido[2.3-d]pyrimidin-6- y1)methyl]amino]benzoyl]-L-glutamic acid,
N-[p-[[(2,4-diamino-7-propylpyrido[2.3-d]pyrimidin-6- y1)methyl]amino]benzoyl]-L-glutamic acid,
N-[p-[[(2,4-diamino-7-phenylpyrido[2.3-d]pyrimidin-6- y1)methyl]amino]benzoyl]-L-glutamic acid,
N-[p-[[(2,4-diamino-7-(2-fluorophenyl)pyrido[2.3-d]- pyrimidin-6-y1)methyl]amino]benzoyl]-L-glutamic acid, N-[p-[[(2,4-diamino-7-(4-nitrophenyl)pyrido[2.3-d]- pyrimidin-6-y1)methyl]amino]benzoyl]-L-glutamic acid, N-[p-[[(2,4-diamino-7-(3-methylphenyl)pyrido[2.3-d]- pyrimidin-6-y1)methyl]amino]benzoyl]-L-glutamic acid, N-[p-[[(2/4-diamino-7-(4-methylphenyl)pyrido[2.3-d]- pyrimidin-6-y1)methyl]amino]benzoyl)-L-glutamic acid N-[p-[[(2,4-diamino-7-(3-methoxyphenyl)pyrido[2.3-d]- pyrimidin-6-y1)methyl]amino]benzoyl]-L-glutamic acid, N-[p-[[(2,4-diamino-7-(4-methoxyphenyl)pyrido(2.3-d]- pyrimidin-6-y1)methyl]amino]benzoyl]-L-glutamic acid N-[p-[[(2,4-diamino-5,7-dimethylpyrido[2.3-d]pyrimidin- 6-y1)methyl]amino]benzoyl]-L-glutamic acid,
N-[p-[[(2/4-diamino-5-methyl-7-phenylpyrido[2.3-d]- pyrimidin-6-y1)methyl]amino]benzoyl]-L-glutamic acid N-[p-[[(2,4-diamino-7-methyl-5-phenylpyrido[2.3-d]- pyrimidin-6-y1)methyl]amino]benzoyl]-L-glutamic acid N-[p-[[(2,4-diamino-5-methyl-7-ethylpyrido[2.3-d]- pyrimidin-6-y1)methyl]amino]benzoyl]-L-glutamic acid N-[p-[[(2,4-diamino-7-methyl-5-ethylpyrido[2.3-d]- pyrimidin-6-y1)methyl]amino]benzoyl]-L-glutamic acid N-[p-[[(2,4-diamino-5-methy1-7-(2-fluorophenyl)pyrido- [2.3-d]pyrimidin-6-y1)methyl]amino]benzoyl]- L-glutamic acid,
N-[p-[[(2,4-diamino-7-methyl-5-(2-fluorophenyl)pyrido- [2.3-d]pyrimidin-6-y1)methyl]amino]benzoyl]-
L-glutamic acid,
N-[p-[[(2,4-diamino-5-methyl-7-(4-nitrophenyl)pyrido- [2.3-d]pyrimidin-6-y1)methyl)amino]benzoyl]- L-glutamic acid, and
N-[p-[[(2,4-diamino-7-methyl-5-(4-nitrophenyl)pyrido- [2.
3-d]pyrimidin-6-y1)methyl]amino]benzoyl]- L-glutamic acid.
4. A method of preparing compounds of claim 1 which comprises: a) contacting a cyanothioacetamide with a 4- substituted alkyl 2-alkoxymethylene-3-oxopropanoate having the structure:
Figure imgf000035_0001
wherein R7 is a lower alkyl group of 1-4 carbons or a phenyl group (Ph) and R is a methyl (Me) or ethyl (Et) group. or with a 3-carbalkoxy propane-1,3-dione having the structure: -34
Figure imgf000036_0002
wherein R5 is a lower alkyl group of 1-4 carbons or a Ph and R and R7 are previously defined under suitable conditions so as to obtain substituted 2-thiopyridine derivative havin the structure:
Figure imgf000036_0001
wherein R, R5 and R7 are as previously defined; b) reacting the substituted 2-thiopyridin derivative with a compound seleted from the group consisting of methyl iodide (Mel), ethyl iodide (Etl), methyl sulfate (Me2SO4), and ethyl sulfate (Et2SO4) so as to obtain 2-alkyl-mercaptopyridine having the structure:
Figure imgf000037_0001
wherein R2 is Me or Et and R, R5 and R7 are previously defined; c) reducing the 2-alkyl-mercaptopyridine to a 5- hydroxymethylpyridine having the structure:
Figure imgf000037_0002
wherein R2, R5 and R7 are previously defined; d) treating the 5-hydroxymethylpyridine so as to obtain an intermediate compound having the structure:
wherein R' is MeOCH2 or PhCH2OCH2 and R2, R5 and R7 are previously defined; e) oxidizing the intermediate compound with an oxidizing agent under suitaeble conditions as to obtain a sulfone of the structure:
Figure imgf000038_0001
wherein R', R2, R5 and R7 are previously defined; f) condensing the sulfone with guanidine to yield.
Figure imgf000038_0002
wherein R' is OCH2OMe or OCH2OPh and R7 ar
Figure imgf000038_0003
wherein R' is OCH2OMe or OCH2OCH2Ph and R5 and R7 are previously defined g) deprotection of the compounds of claim 4(f) to yield the corresponding 6- hydroxymethylpyrido[2,3-d]pyrimidines. wherein R' is OH and R5 and R7 are previously defined h) bromination of the compounds derived in claim
4(g) to yield 6-hydroxymethyl derivatives.
Figure imgf000039_0002
wherein R' is Br and R5 and R7 are previously defined i) condensation of the compound, derived in claim 4(h) followed by saponification to yield:
Figure imgf000039_0003
wherein R5 is hydrogen atom, a lower alkyl group of 1 - 4 carbons or a phenyl group (Ph), R7 is a lower alkyl group of 1 - 4 carbons or a Ph, and R10 is a hydrogen atom, a methyl group or an ethyl group.
5. A method of claim 4, wherein the contacting in step (a) is effected in the presence of a lower alkyl alcohol solvent.
6. A method of claim 5, wherein the lower alkyl alcohol solvent is methanol, ethanol or propanol.
7. A method of claim 4, wherein the reacting in step
(b) is effected in the presence of a polar solvent.
8. A method of claim 7, wherein the polar solvent comprises potassium carbonate.
9. A method of claim 4, wherein the reducing in step
(c) is effected by reacting with lithium aluminum hydride in an inert solvent.
10. A method of claim 9, wherein the inert solvent is diethyl ether.
11. A method of claim 4, wherein the reducing in step {c) is performed at a temperature in the range of -78ºC to 25ºC.
12. A method of claim 4, wherein the reducing in step (c) is performed for a period of 2 to 8 hours.
13. A method of claim 4 wherein the treating in step (d) is effected by contacting with chloromethyl methyl ether or chloromethyl benzyl ether.
14. A method of claim 13, wherein the contacting is effected in an inert chlorinated hydrocarbon solvent.
15. A method of claim 14, wherein the solvent is chloroform.
16. A method of claim 14, wherein the contacting is effected in a base.
17. A method of claim 16, wherein the base is 4-dimethyl-amino pyridine.
18. A method of claim 17, wherein the contacting is effected at a temperature in the range from -5ºC to 50ºC.
19. A method of claim 18, wherein the contacting is effected for a period of from 1 to 10 hours.
20. A method of claim 4, wherein the oxidizing agent of step (e) is sodium hypochlorate, hydrogen peroxide or m-chloroperbenzoic acid.
21. A method of claim 4, wherein the suitable conditions of step (e) comprise oxidizing in an inert, chlorinated hydrocarbon solvent or alcohol.
22. A method of claim 21, wherein the alcohol is ethanol.
23. A method of claim 4, wherein the suitable conditions of step (e) comprise oxidizing at room temperature for a period from 30 minutes to 2 hours.
24. A method of claim 4, wherein the condensing of step (e) comprises treatment with free guanidine in refluxing alcohols.
25. A method of claim 21, wherein the refluxing alcohols are chosen from methanol, ethanol or propanol.
26. A method of claim 4, wherein the condensing of step (f) is effected in a temperature range of from 100ºC-210ºC.
27. A method of claim 26, wherein the condensing of step (f) is performed for a period of 2-8 hours.
28. A method of claim 4, wherein the condensing of step (f) is effected in a high boiling inert solvent.
29. A method of claim 28, wherein the solvent is diglyme or diphenyl ether.
30. A method of claim 4, wherein the condensing of step (f) is performed in a temperature range of from 160ºC-210ºC.
31. A method of claim 4, wherein the condensing of step (f) is performed for a period of 2-8 hours.
32. A method of claim 4, wherein deprotection of step (g) is effected by treatment with concentrated hydrochloric acid in alcohol.
33. A method of claim 4, wherein deprotection of step (g) is effected at reflux temperature for 2 to 6 hours.
34. A method of claim 4, wherein deprotection of step (g) is effected by treatment with a Lewis acid.
35. A method of claim 34, wherein the Lewis acid is borontrichloride.
36. A method of claim 4, wherein the deprotection of step (g) is effected in an inert chlorinated hydrocarbon solvent.
37. A method of claim 36, wherein the solvent is methlene chloride
38. A method of claim 4, wherein the deprotection of step (g) is performed at a temperature range of from
78ºC to 25ºC.
39. A method of claim 4, wherein the deprotection of step 4(g) is performed for a period of from 2-24 hours.
40. A method of claim 4, wherein the brominating agent of step (h) is hydrogen bromide in dioxan.
41. A method of claim 4, wherein condensation of step (i) is with diethyl (p-aminobenzoyl)-L-glutamate.
42. An intermediate compound having the structure:
Figure imgf000043_0001
wherein R5 and R7 are the same or different and are lower alkyl groups of 1-4 carbon atoms or phenyl groups and R is a methyl or ethyl group.
43. An intermediate compound of claim 42 selected from the group consisting of.
3-cyano-5-(ethoxycarbonyl)-6-methylpyridine-2(1H)- thione,
3-cyano-5-(ethoxycarbonyl)-6-ethoxymethylpyridine- 2(1H)-thione,
3-cyano-5-(ethoxycarbonyl)-6-ethylpyridine-2(1H)- thione,
3-cyano-5-(ethoxycarbonyl)-6-propylpyridine-2(1H)- thione,
3-cyano-5-(ethoxycarbonyl)-6-phenylpyridine-2(1H)- thione,
3-cyano-5-(ethoxycarbonyl)-6-(2-fluorophenyl)pyridine- 2(1H)-thione,
3-cyano-5-(ethoxycarbonyl)-6-(4-nitrophenyl)pyridine- 2(1H)-thione,
3-cyano-5-(ethoxycarbonyl)-6-(4-methylphenyl)pyridine- 2(1H)-thione,
3-cyano-5-(ethoxycarbonyl)-6-(3-methylphenyl)pyridine- 2(1H)-thione,
3-cyano-5-(ethoxycarbonyl)-6-(4-methoxyphenyl)pyridine- 2(1H)-thione,
3-cyano-5-(ethoxycarbonyl)-6-(3-methoxyphenyl)pyridine- 2(1H)-thione,
3-cyano-5-(ethoxycarbonyl)-4,6-dimethylpyridine-2(1H)- thione.
3-cyano-5-(ethoxycarbonyl)-4-methyl-6-phenylpyridine- 2(1H)-thione,
3-cyano-5-(ethoxy-carbonyl)-6-methyl-4-phenylpyridine- 2(1H)-thione. 3-cyano-5-(ethoxycarbonyl)-6-ethyl-4-methylpyridine- 2(1H)-thione,
3-cyano-5-(ethoxycarbonyl)-4-ethyl-6-methylpyridine- 2(1H)-thione,
3-cyano-5-(ethoxycarbonyl)-4-methyl-6-propylpyridine- 2(1H)-thione,
3-cyano-5-(ethoxycarbonyl)-6-methyl-4-propylpyridine- 2(1H)-thione,
3-cyano-5-(ethoxycarbonyl)-4-methyl-6-phenylpyridine- 2(1H)-thione,
3-cyano-5-(ethoxycarbonyl)-6-methyl-4-phenylpyridine- 2(1H)-thione,
3-cyano-5-(ethoxycarbonyl)-4-(2-fluorophenyl)-6-methyl- pyridine-2(1H)-thione,
3-cyano-5-(ethoxycarbonyl)-6-(2-fluorophenyl)-4-methyl- pyridine-2(1H)-thione,
3-cyano-5-(ethoxycarbonyl)-4-methyl-6-(4-nitrophenyl)pyridine-2(1H)-thione, and
3-cyano-5-(ethoxycarbonyl)-6-methyl-4-(4-nitrophenyl)pyridine-2(1H)-thione.
44. A 2-Methylmercaptopyridine intermediate compound having the structure:
Figure imgf000045_0001
wherein R5 and R7 are the same or different and are lower alkyl groups of 1-4 carbon atoms or phenyl groups, R2 and R are the same or different and are methyl or ethyl groups.
45. An intermediate compound of claim 44 selected from the group consisting of:
3-cyano-5-(ethoxycarbonyl)-6-methy1-2-methylmercapto- pyridine,
3-cyano-5-(ethoxycarbonyl)-6-ethyl-2-methylmercapto- pyridine,
3-cyano-5-(ethoxycarbonyl)-2-methylmercapto-6-propylpyridine,
3-cyano-5-(ethoxycarbonyl)-2-methylmercapto-6-phenyl- pyridine,
3-cyano-5-(ethoxycarbonyl)-6-(2-fluorophenyl)-2-methyl- mercaptopyridine,
3-cyano-5-(ethoxycarbonyl)-2-methylmercapto-6-(4-nitrophenyl)-pyridine,
3-cyano-5-(ethoxycarbonyl)-2-methylmercapto-6-(4- methylphenyl)-pyridine,
3-cyano-5-(ethoxycarbonyl)-2-methylmercapto-6-(3- methylphenyl)-pyridine,
3-cyano-5-(ethoxycarbonyl)-2-methylmercapto-6-(4-methoxyphenyl)-pyridine,
3-cyano-5-(ethoxycarbonyl)-2-methylmercapto-6-(3-methoxyphenyl)-pyridine,
3-cyano-5-(ethoxycarbonyl)-4,6-dimethyl-2-methyl- mercaptopyridine,
3-cyano-5-(ethoxycarbonyl)-4-ethyl-6-methyl-2-methyl- mercaptopyridine,
3-cyano-5-(ethoxycarbonyl)-6-ethyl-4-methyl-2-methyl- mercaptopyridine,
3-cyano-5-(ethoxycarbonyl)-4-methyl-2-methylmercapto-6- propylpyridine,
3-cyano-5-(ethoxycarbonyl)-6-methyl-2-methylmercapto-4- propylpyridine, 3-cyano-5-(ethoxycarbonyl)-4-methyl-2-methylmercapto-6- phenylpyridine,
3-cyano-5-(ethoxycarbonyl)-6-methyl-2-methylmercapto-4- phenyIpyridine,
3-cyano-5-(ethoxycarbonyl)-4-(2-fluorophenyl)-6-methyl- 2-methylmercaptopyridine,
3-cyano-5-(ethoxycarbonyl)-6-(2-fluorophenyl)-4-methyl- 2-methylmercaptopyridine,
3-cyano-5-(ethoxycarbonyl)-4-methyl-2-methylmercaptopyridine-6-(4-nitrophenyl)pyridine, and
3-cyano-5-(ethoxycarbonyl)-6-methyl-2-methylmercapto-4- (4-nitrophenyl)pyridine.
46. A 5-Hydroxypyridine intermediate compound having the structure:
Figure imgf000047_0001
wherein R5 and R7 are the same or different and are lower alkyl groups of 1-4 carbon atoms or phenyl groups and R2 is a methyl or ethyl group.
47. An intermediate compound of claim 46 selected from the group consisting of.
3-cyano-5-hydoxymethyl-6-methyl-2-methylmercaptopyridine,
3-cyano-5-hydoxymethyl-6-ethyl-2-methylmercaptopyridine,
3-cyano-5-hydoxymethyl-6-ethoxymethy1-2-methylmercaptopyridine, 3-cyano-5-hydoxymethyl-2-methylmercapto-6-propylpyridine,
3-cyano-5-hydoxymethyl-2-methylmercapto-6-phenylpyridine,
3-cyano-5-hydoxymethyl-6-(2-fluorophenyl)-2-methyl- mercaptopyridine,
3-cyano-5-hydoxymethyl-6-(4-nitrophenyl)-2-methylmercaptopyridine,
3-cyano-5-hydoxymethyl-6-(3-methylphenyl)-2-methyl- mercaptopyridine,
3-cyano-5-hydoxymethyl-6-(4-methylphenyl)-2-methyl- mercaptopyridine,
3-cyano-5-hydoxymethyl-6-(3-methoxyphenyl)-2-methyl- mercaptopyridine,
3-cyano-5-hydoxymethyl-6-(4-methoxyphenyl)-2-methyl- mercaptopyridine,
3-cyano-5-hydoxymethyl-4,6-dimethyl-2-methylmercaptopyridine,
3-cyano-5-hydoxymethyl-4-methyl-2-methylmercaptopyridine,
3-cyano-5-hydoxymethyl-6-methyl-2-methylmercaptopyridine,
3-cyano-5-hydoxymethyl-4-methyl-2-methylmercapto-6- phenylpyridine,
3-cyano-5-hydoxymethyl-6-methyl-2-methylmercapto-4- phenylpyridine,
3-cyano-4-(2-fluorophenyl)-5-hydroxymethyl-6-methyl-2- methylmercaptopyridine,
3-cyano-4-(2-fluorophenyl)-5-hydroxymethyl-4-methyl-2- methylmercaptopyridine,
3-cyano-5-hydoxymethyl-4-methyl-2-methylmercapto-6-(4- nitrophenyl)pyridine, and
3-cyano-5-hydoxymethyl-6-methyl-2-methylmercapto-4-(4- nitrophenyl)pyridine,
47. A 5-(Methoxymethoxy)methylpyridine intermediat compound having the structure:
Figure imgf000049_0001
wherein R5 and R7 are the same or different an are lower alkyl groups of 1-4 carbon atoms o phenyl groups, R2 and R are the same or differen and are methyl or ethyl groups and R' is CH3OCH2 or PhCH2OCH2.
48. An intermediate compound of claim 47 selected from the group consisting of.
3-cyano-5-(methoxymethoxy)methyl-6-methyl-2-methyl- mercaptopyridine,
3-cyano-5-(methoxymethoxy)methyl-2-methylmercapto-6- propylpyridine,
3-cyano-5-(methoxymethoxy)methyl-2-methylmercapto-6- phenylpyridine,
3-cyano-5-(2-fluorophenyl)-5-(methoxymethoxy)methyl-2- methylmercaptopyridine,
3-cyano-5-(methoxymethoxy)methyl-2-methylmercapto-6-(4- nitrophenyl)pyridine,
3-cyano-5-(methoxymethoxy)methyl-2-methylmercapto-6-(3- methylphenyl)pyridine,
3-cyano-5-(methoxymethoxy)methyl-2-methylmercapto-6-(4- methylphenyl)pyridine,
3-cyano-5-(methoxymethoxy)methyl-2-methylmercapto-6-(3- methoxyphenyl)pyridine, 3-cyano-5-(methoxymethoxy)methyl-2-methylmercapto-6-(4- methoxyphenyl)pyridine,
3-cyano-5-(methoxymethoxy)methyl-4,6-dimethyl-2-methyl- mercaptopyridine,
3-cyano-6-ethyl-5-(methoxymethoxy)methyl-4-methyl-2- methylmercaptopyridine,
3-cyano-4-ethyl-5-(methoxymethoxy)methyl-6-methyl-2- methyl mercaptopyridine,
3-cyano-5-(methoxymethoxy)methyl-4-methyl-2-methyl- mercapto-6-phenyIpyridine,
3-cyano-5-(methoxymethoxy)methyl-6-methyl-2-methyl- mercapto-4-phenyIpyridine,
3-cyano-5-(2-fluorophenyl)-5-(methoxymethoxy)methyl-6- methyl-2-methylmercaptopyridine,
3-cyano-5-(2-fluorophenyl)-5-(methoxymethoxy)methyl-4- methyl-2-methylmercaptopyridine,
3-cyano-5-(methoxymethoxy)methyl-4-methyl-2-methyl- mercapto-6-(4-nitrophenyl)pyridine, and
3-cyano-5-(methoxymethoxy)methyl-6-methyl-2-methyl- mercapto-4-(4-nitrophenyl)pyridine,
49. A 2-Methylsulfonylpyridine intermediate compound of having the structure:
Figure imgf000050_0001
wherein R5 and R7 are the same or different and are lower alkyl groups of 1-4 carbon atoms or phenyl groups, R2 is an ethyl or methyl group and R' is
CH3OHCH2 or PhCH2OCH2.
50. An intermediate compound of claim 44 selected from the group consisting of.
3-cyano-5-(methoxymethoxy)methyl-6-methyl-2-methyl- sulfonylpyridine,
3-cyano-6-ethyl-5-(methoxymethoxy)methyl-2-methyl- sulfonylpyridine,
3-cyano-5-(methoxymethoxy)methyl-2-methylsulfonyl-6- propylpyridine,
3-cyano-5-(methoxymethoxy)methyl-2-methylsulfonyl-6- phenylpyridine,
3-cyano-6-(2-fluorophenyl)-5-(methoxymethoxy)methyl-2- methylsulfonylpyridine,
3-cyano-5-(methoxymethoxy)methyl-2-methylsulfonyl-6-(4- nitrophenyl)pyridine,
3-cyano-5-(methoxymethoxy)methyl-6-(3-methylphenyl)-2- methylsulfonylpyridine,
3-cyano-5-(methoxymethoxy)methyl-6-(4-methylphenyl)-2- methylsulfonylpyridine,
3-cyano-5-(methoxymethoxy)methyl-6-(3-methoxyphenyl)-2- methylsulfonylpyridine,
3-cyano-5-(methoxymethoxy)methyl-6-(4-methoxyphenyl)-2- methylsulfonylpyridine,
3-cyano-5-(methoxymethoxy)methyl-4,6-dimethyl-2-methyl- sulfonylpyridine,
3-cyano-5-(methoxymethoxy)methyl-4-methyl-2-methyl- sulfonyl-6-phenylpyridine, .
3-cyano-5-(methoxymethoxy)methyl-6-methyl-2-methyl- sulfonyl-4-phenyIpyridine,
3-cyano-6-ethyl-5-(methoxymethoxy)methyl-4-methyl-2- methylsulfonylpyridine,
3-cyano-4-ethyl-5-(methoxymethoxy)methyl-6-methyl-2- methylsulfonylpyridine,
3-cyano-6-(2-fluorophenyl)-5-(methoxymethoxy)methyl-4- methyl-2-methylsulfonylpyridine, 3-cyano-4-(2-fluorophenyl)-5-(methoxymethoxy)methyl-6- methyl-2-methylsulfonylpyridine,
3-cyano-5-(methoxymethoxy)methyl-4-methyl-2-methyl- sulfonyl-6-(4-nitrophenyl)pyridine, and
3-cyano-5-(methoxymethoxy)methyl-6-methyl-2-methyl- sulfonyl-4-(4-nitrophenyl)pyridine.
51. A Pyrido[2.3-d]pyrimidine intermediate compound having the structure:
Figure imgf000052_0001
wherein R5 and R7 are the same or different and are lower alkyl groups of 1-4 carbon atoms or phenyl groups and R' is OCH2OCH3 or OCH2OPh or
Figure imgf000052_0002
wherein R5 and R7 are the same or different and are lower alkyl groups of 1-4 carbon atoms or phenyl groups and R' is OCH2OCH3 or OCH2OCH2Ph.
52. An intermediate compound of claim 51 selected from the group consisting of.
2,4-diamino-6-(methoxymethoxy)methyl-7-methylpyrido[2.3-d]pyrimidine, 2,4-diamino-6-(methoxymethoxy)methyl-7-ethylpyrido[2.3- d]pyrimidine,
2,4-diamino-6-(methoxymethoxy)methyl-7-propylpyrido[2.3-d]pyrimidine,
2,4-diamino-6-(methoxymethoxy)methyl-7-phenylpyrido[2.3-d]pyrimidine,
2,4-diamino-6-(methoxymethoxy)methyl-7-(2- fluorophenyl)pyrido[2.3-d]pyrimidine,
2,4-diamino-6-(methoxymethoxy)methyl-7-(4- nitrophenyl)pyrido[2.3-d]pyrimidine,
2,4-diamino-6-(methoxymethoxy)methyl-7-(3- methylphenyl)pyrido[2.3-d]pyrimidine,
2,4-diamino-6-(methoxymethoxy)methyl-7-(4- methylphenyl)pyrido[2.3-d]pyrimidine,
2,4-diamino-6-(methoxymethoxy)methyl-7-(3- methoxyphenyl)pyrido[2.3-d]pyrimidine,
2,4-diamino-6-(methoxymethoxy)methyl-7-(4- methoxyphenyl)pyrido[2.3-d]pyrimidine,
2,4-diamino-6-(methoxymethoxy)methyl-5,7- dimethylpyrido[2.3-d]pyrimidine,
2,4-diamino-6-(methoxymethoxy)methyl-5-phenylpyrido- [2.3-d]pyrimidine,
2,4-diamino-6-(methoxymethoxy)methyl-7-methyl-5- phenylpyrido[2.3-d]pyrimidine,
2,4-diamino-6-(methoxymethoxy)methyl-5-ethyl-7- methylpyrido[2.3-d]pyrimidine,
2,4-diamino-6-(methoxymethoxy)methyl-7-ethyl-5- methylpyrido[2.3-d]pyrimidine,
2,4-diamino-6-(methoxymethoxy)methyl-5-methyl-7-(2- fluorophenyl)pyrido[2.3-d]pyrimidine,
2,4-diamino-6-(methoxymethoxy)methyl-7-methyl-5-(2- fluorophenyl)pyrido[2.3-d]pyrimidine,
2,4-diamino-6-(methoxymethoxy)methyl-5-methyl-7-(4- nitrophenyl)pyrido[2.3-d]pyrimidine, and 2,4-diamino-6-(methoxymethoxy)methyl-7-methyl-5-(4- nitrophenyl)pyrido[2.3-d]pyrimidine.
53. A pyrido[2.3-d]pyrimidine intermediate compound having the structure:
Figure imgf000054_0001
wherein R5 and R7 are the same or different and are lower alkyl groups of 1-4 carbon atoms or phenyl groups and R' is OH.
54. An intermediate compound of claim 53 selected from the group consisting of. 2,4-diamino-6-hydroxymethyl-7-methylpyrido[2.3- d]pyrimidine,
2,4-diamino-6-hydroxymethyl-7-ethylpyrido[2.3- d]pyrimidine,
2,4-diamino-6-hydroxymethyl-7-propylpyrido[2.3- d]pyrimidine,
2,4-diamino-6-hydroxymethyl-7-phenylpyrido[2.3- d]pyrimidine,
2,4-diamino-6-hydroxymethyl-7-(2- fluorophenyl)pyrido[2.3-d]pyrimidine,
2,4-diamino-6-hydroxymethyl-7-(4- nitrophenyl)pyrido[2.3-d]pyrimidine,
2,4-diamino-6-hydroxymethyl-7-(3- methylphenyl)pyrido[2.3-d]pyrimidine,
2,4-diamino-6-hydroxymethyl-7-(4- methylphenyl)pyrido[2.3-d]pyrimidine, 2,4-diamino-6-hydroxymethyl-7-(3- methoxyphenyl)pyrido[2.3-d]pyrimidine,
2,4-diamino-6-hydroxymethyl-7-(4- methoxyphenyl)pyrido[2.3-d)pyrimidine,
2,4-diamino-6-hydroxymethyl-5,7-dimethylpyrido[2.3- d]pyrimidine,
2,4-diamino-6-hydroxymethyl-5-methyl-7- phenylpyrido[2.3-d]pyrimidine,
2,4-diamino-6-hydroxymethyl-7-methyl-5- phenylpyrido[2.3-d]pyrimidine,
2,4-diamino-6-hydroxymethyl-5-methyl-7-ethylpyrido[2.3- d]pyrimidine,
2,4-diamino-6-hydroxymethyl-7-methyl-5-ethylpyrido[2.3- d]pyrimindine,
2,4-diamino-6-hydroxymethyl-5-methyl-7-(2- fluorophenyl)pyrido[2.3-d]pyrimidine,
2,4-diamino-6-hydroxymechyl-7-methyl-5-(2- fluorophenyl)pyrido[2.3-d]pyrimidine,
2,4-diamino-6-hydroxymethyl-5-methyl-7-(4- nitrophenyl)pyrido[2.3-d]pyrimidine, and
2,4-diamino-6-hydroxymethyl-7-methyl-5-(4- nitrophenyl)pyrido[2.3-d]pyrimidine.
55. A pharmaceutical composition comprising the compound of claim 1 or a pharmaceutically acceptable acid salt thereof together with a pharmaceutically acceptable carrier.
56. A method of killing tumor cell comprising contacting the tumor cells with the compound of claim
55.
57. A method of treating a subject having a tumor which comprises administering to the subject an effective tumor-killing amount of the composition of claim 55,
PCT/US1989/002725 1988-07-01 1989-06-22 5-deaza-5,7-disubstituted-aminopterin analogues WO1990000172A1 (en)

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WO1993022312A1 (en) * 1992-04-29 1993-11-11 Sri International Deazaaminopterins for treatment of inflammation
WO2010016846A1 (en) * 2008-08-08 2010-02-11 Kalypsys, Inc. Heterocyclic modulators of tgr5 for treatment of disease

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