合成路线1

The condensation of 6-methylpyridine-3-carboxaldehyde (I) with malonic acid (II) by means of piperidine in refluxing pyridine gives 3-(6-methyl-3-pyridyl)acrylic acid (III), which is esterified with ethanol and H2SO4 as usual to afford ethyl 3-(6-methyl-3-pyridyl)acrylate (IV). The reduction of (IV) with H2 over Pd/C in ethanol affords ethyl 3-(6-methyl-3-pyridyl)propionate (V), which is cyclized with ethyl formate (VI) and thiourea (VII) by means of Na in ether-ethanol yielding 5-(6-methyl-3-pyridylmethyl)-2-thiouracil (VIII). The methylation of (VIII) with methyl iodide and NaOH in hot water gives 5-(6-methyl-3-pyridyl-methyl)-2-methylthio-4-pyrimidone (IX), which is finally condensed with 2-[(5-dimethylaminomethylfuran-2-yl)methylthio]ethylamine (X) in refluxing pyridine.

合成路线2

A new synthesis of BVAU has been described: The condensation of 1-(beta-D-arabinofuranosyl)-5-formyluracil (I) with malonic acid (II) by means of piperidine in hot anhydrous pyridine gives the carboxyvinyl derivative (III), which is then treated with N-bromosuccinimide in basic medium.

合成路线3

2-Chloro-3-nitropyridine (I) is condensed with diethyl 2-(2-cyanoethyl)malonate (II) by means of NaH in refluxing THF fo give 1-cyano-3,3-bis(ethoxycarbonyl)-3-(3-nitro-2-pyridinyl)propane (III), which is hydrolyzed with NaOH io aqueous ethanol and decarboxylated in aqueous HCl to afford 2-(3-cyanopropyl)-3-nitropyridine (IV). Hydrogenation of (IV) over Pd/C in ethanol gives 3 amino-2-(3-cyanopropyl)pyridine (V), which is diazotized with NaNO2 in dilute H2SO4 and hydrolyzed to 2-(3-cyanopropyl)-3-hydroxypyridine (VI). Methylation of (VI) with MeI by means of NaH in Me2SO yields 2-(3-cyanopropyl)-3-methoxypyridine (VII), which is then reduced with LiAlH4 to provide 2-(4-amino-butyl)-3-methoxypyridine (VIII). The final stage is to condense (VIII) with 2-nitroamino-5-(6-methyl)-3-pyridinylmethyl)-4-pyrimidinone (XIII) in refluxing pyridine. Synthesis of the pyrimidinone (XIII) reagent commences with 2-methylpyridine-4-aldehyde (IX), which is condensed with malonic acid and decarboxylated in pyridine containing piperidine to afford 3-(6-methyl-3pyridinyl)acrylic acid (X). Esterification of (X) with ethanol-H2SO4, followed by reduction with H2 over Pd/C in ethanol gives ethyl (2-mcthyl-5-pyridinyl)ethanoate (XI), which with ethyl formate in the presence of NaH in glyme furnishes 1-(ethoxycarbonyl)-1-formyl-2-(2 methyl-5-pyridinyl)ethane (XII). Condensation of (XII) with nitroguanidine in ethanol in the presence of NaOEt provides the 4-pyrimidinone (XIII).

合成路线4

The acetylation of 2-methyl-3-aminobenzonitrile (I) with acetic anhydride in refluxing acetic acid gives 2-methyl-3-acetylaminobenzonitrile (II), which is reduced with Raney-Ni in refluxing 50% formic acid yielding 2-methyl-3-acetylaminobenzaldehyde (III). The condensation of (III) with malonic acid (IV) by means of piperidine in pyridine affords 2-methyl-3-acetylaminocinn acid (V), which is converted to the corresponding azide (VI) by reaction with ethyl chloroformate and sodium azide by means of triethylamine in acetone. The cyclization of (VI) by heating at 240 C in diphenyl ether gives 1-hydroxy-5-methyl-6-acetylaminoisoquinoline (VII), which is hydrolyzed with HCl in refluxing ethanol to 1-hydroxy-5-methyl-6-aminoisoquinoline (VIII). The condensation of (VIII) with 4-chloro-3-nitropyridine (IX) in DMF affords 1-hydroxy-5-methyl-6-[(3-nitro-4-pyridyl)amino]isoquinoline (X).

合成路线5

The reaction of trimethylene glycol (I) with PCl3 gives 2-chloro-1,3,2-dioxaphosphorinane (II), which is condensed with propargyl alcohol (III) by means of triethylamine in acetonitrile to give a mixture of 2-allenyl- and 2-propargyl-2-oxo-1,3,2-dioxaphosphorinane (IV and V). The reaction of this mixture with isobutylamine in acetonitrile affords 2-(2-isobutylamino-1-propenyl)-2-oxo-1,3,2-dioxaphosphorinane (VI). The hydrolysis of the enamine (VI) with malonic acid gives 2-acetonyl-2-oxo-1,3,2-dioxaphosphorinane (VII), which is condensed with isobutyl-(2-nitrobenzylidene)amine (VIII) to yield 2-[1-(2-nitrobenzylidene)-2-oxopropyl]-2-oxo-1,3,2-dioxaphosphorinane (IX). Finally, this compound is cyclized with methyl 3-aminocrotonate (X) in refluxing acetonitrile.

合成路线6

The reaction of 2-chloro-4-cyanopyridine (I) with sodium methoxide in refluxing methanol gives 2-methoxy-4-cyanopyridine (II), which by reduction with H2 over Raney-Ni and semicarbazide HCl in water-ethanol is converted to 2-methoxypyridine-4-carboxyaldehyde (III). The condensation of (III) with malonic acid (IV) by means of piperidine in hot pyridine yields 3-(2-methoxy-4-pyridyl)acrylic acid (V), which is esterified with ethanol and H2SO4 to the ethyl ester (VI). The reduction of (VII) with H2 over Pd/C in ethanol affords the corresponding propionate (VII). Formylation of (VII) with ethyl formate and NaH gives ethyl 2-formyl-3-(2-methoxy-4-pyridyl)propionate (VIII), which is cyclized with nitroguanidine (IX) by means of sodium methoxide in refluxing methanol yielding 2-nitroamino-5-12-methoxy-4-pyridylmethylpyrimidin-4(1H)-one (X). The reaction of (X) with 2-[5-(dimethylaminomethyl)-2 furylmethylthio]ethylamine in refluxing ethanol gives the O-methyl derivative of SK&F 93574 (XII), whicn is finally deprotected with HCl in refluxing ethanol.

合成路线7

This compound can be obtained by two related ways: 1) The cyclization of 3-cyclohexylpropionitrile (I) with thiosemicarbazide (II) by means of trifluoroacetic acid gives 5-(2-cyclohexylethyl)-1,3,4-thiadiazol-2-amino (III), which is submitted to a new cyclization process with bis(2,4,6-trichlorophenyl)malonate (IV) in refluxing xylene yielding 2-(2-cyclohexylethyl)-7-hydroxy-5H-1,3,4-thiadiazolo[3,2-a]pyrimidin-5-one (V) (1-3). The nitration of (V) with fuming nitric acid in acetic acid affords the corresponding 7-hydroxy-6-nitro derivative (VI), which is treated with POCl3 and tripropylamine to afford the 7-chloro-6-nitro derivative (VII). The reaction of (VII) with concentrated aqueous NH4OH in ethanol gives the corresponding 7-amino-6-nitro compound (VIII), which is reduced with Sn-HCl in dioxane-water to afford the 6,7-diamino derivative (IX). Finally, this compound is dissolved in aqueous HCl and treated with NaNO2. 2) The cyclization of 3-cyclohexylpropionic acid (X) with thiosemicarbazide (II) by means of hot H2SO4 gives the thiadiazole (III), which is cyclized again with malonic acid (XI) by means of POCl3 in hot toluene to afford the previously obtained thiadiazolopyrimidine (V).

合成路线8

In the original synthesis of the title compound, Knoevenagel condensation of benzaldehyde (I) with malonic acid (II) in the presence of ammonium acetate produced the beta-aminoacid (III). Reductive alkylation of the amino group of (III) with formaldehyde produced the dimethyl amine (IV). Then, Fischer esterification of (IV) with ethanolic HCl furnished the intermediate amino ester (V). Amino ester (V) was alternatively obtained by Michael addition of dimethylamine to ethyl cinnamate (VI). Reduction of the ester function of (V) provided amino alcohol (VII). The sodium alkoxide of (VII) was then coupled with 1-fluoronaphthalene (VIII) to produce the racemic amino ether, which was finally resolved into enantiomers by means of tartaric acid.

合成路线9

The condensation of 2-methylquinolin-8-ol (I) with 2,6-dichloro-3-nitrobenzyl chloride (II) by means of NaH in DMF gives the corresponding benzyl ether (III), which is reduced with Fe and HCl in methanol/water to the aniline (IV). The acylation of (IV) with 2-phthalimidoacetyl chloride (V) by means of DMAP and pyridine yields the amide (VI), which is methylated at the amidic nitrogen with NaH and methyl iodide in DMF to the N-methylanilide (VII). Elimination of the phthalimido group of (VII) with hydrazine in refluxing ethanol affords the glycine anilide (VIII), which is acylated with the acrylic acid (IX) by means of 1-[3-dimethylamino)propyl]-3-ethylcarbodiimide (DECD) and HOBT in DMF. The intermediate substituted acrylic acid (IX) has been obtained by reaction of 6-acetamidopyridine-3-carbaldehyde (X) with malonic acid and pyridine in refluxing ethanol.

合成路线10

Knoevenagel condensation of aldehyde (I) with malonic acid (II) provided substituted cinnamic acid (III). This was condensed with amino compound (IV) in the presence of 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide.HCl (EDC) and 1-hydroxy-benzotriazole (HOBt) to give amide (V), which was then converted to the hydrochloride salt by reaction with methanolic HCl.

合成路线11

Knoevenagel condensation of pyridine-3-carboxaldehyde (I) with malonic acid in the presence of ammonium acetate afforded the racemic amino acid (III), which was acylated with phenylacetyl chloride (IV) to give amide (V). Optical resolution of (V) by means of penicillin amidase produced the hydrolysis of the undesired (R)-enantiomer. After isolation of the unreacted (S)-enantiomer (VI), its hydrolysis with aqueous HCl furnished the chiral amino acid (VII), which was converted to methyl ester (VIII) with 2,2-dimethoxypropane in MeOH. Coupling of (VIII) with N-Boc-(R)-nipecotic acid (IX) using 2-benzotriazolyl-1,1,3,3-tetramethyluronium hexafluorophosphate (HBTU) provided amide (X). Deprotection of the Boc group of (X) was then achieved with HCl in dioxan resulting amine (XI).

合成路线12

Condensation of veratraldehyde (I) with malonic acid and ammonium acetate in refluxing EtOH afforded 3-amino-3-(3,4-dimethoxyphenyl)propionic acid (II). The N-phthaloyl group was introduced in (II) by treatment with N-carbethoxyphthalimide (III) in the presence of Na2CO3. The resulting phthalimido acid (IV) was converted to the title amide via activation with carbonyl diimidazole, followed by treatment with ammonium hydroxide.

合成路线13

The reaction of 2-methoxy-9-methylcarbazole-3-carbaldehyde (I) with malonic acid gives the propenoic acid (III), which by treatment with sodium azide and ethyl chloroformate is converted into the azide (IV). The cyclization of (IV) in refluxing ortho-dichlorobenzene affords 5-methoxy-7-methyl-2,7-dihydro-1H-pyrido [4,3-c]carbazol-1-one (V), which by treatment with POCl3 is converted into the 1-chloro derivative (VI). Finally, this compound is dechlorinated by hydrogenation with H2 over Pd/C.

合成路线14

The reaction of 3-acetamido-4-methylbenzaldehyde (I) with malonic acid by means of piperidine in hot pyridine gives 3-(3-acetamido-4-methylphenyl)-2(E)-propenoic acid (II), which by reaction first with ethyl chloroformate and then with sodium azide yields the corresponding azide (III). The thermal cyclizaton of (III) affords the isoquinolinone (IV), which is treated with HCl in refluxing ethanol to give 6-amino-7-methylisoquinolin-1(2H)-one (V). The reaction of (V) with refluxing POCl3 yields the 1-chloroisoquinoline (VI), which is protected by reaction with phenzophenoneimine and HCl in methanol to afford 1-chloro-6-(diphenylmethyleneamino)-7-metylisoquinoline (VII). The bromination of (VII) with NBS and benzoyl peroxide in refluxing CCl4 gives the bromomethyl derivative (VIII), which is condensed with 3(S)-(tert-butoxycarbonylamino)pyrrolidin-2-one (IX) (obtained by cyclization of the diaminobutyric acid (X) by means of HOBT in THF) by means of NaH in THF/DMF yielding the N-substituted pyrrolidone (XI). The deprotection of (XI) with HCl afford the diamino intermediate (XII), which is selectively acylated with thieno[3,2-b]pyridine-2-sulfonyl chloride (XIII) by means of triethylamine in acetonitrile giving the sulfonamidde (XIV). Finally, this compound is treated with ammonium acetate in hot phenol. The intermediate sulfonyl chloride (XIII) has been obtained as follows: The reaction of 2-ethynylpyridine (XV) with benzylthiol and sodium ethoxide in ethanol gives 2-[2-(benzylsulfanyl)vinyl]pyridine (XVI), which is cyclized at 625 C yielding thieno[3,2-bpyridine (XVII). Finally, this compound is chlorosulfonated by reaction with BuLi, SO2 and SO2Cl2 in THF.

合成路线15

The intermediate silyl sulfide (II) was prepared by palladium-catalyzed displacement of 5-bromo-1-methylindole (I) with potassium (triisopropylsilyl)sulfide. Alternatively, 5-iodoindole (III) was N-methylated with iodomethane and NaH, yielding 5-iodo-1-methylindole (IV), which was then reacted with potassium (triisopropylsilyl)sulfide to give (II). Condensation of silyl sulfide (II) with the aryl triflate (V) in the presence of CsF as the desilylating reagent furnished the diaryl sulfide (VI). Knoevenagel condensation of aldehyde (VI) with malonic acid (VII) gave rise to the cinnamic acid derivative (VIII). This was then coupled with ethyl isonipecotate (IX), producing amide (X). The ethyl ester of (X) was finally hydrolyzed with NaOH to yield the title sodium carboxylate salt.

合成路线16

合成路线17

Uracil intermediate (I) is obtained as follows. Condensation of 2-fluoro-4-iodophenyl isocyanate (XIII) with cyclopropylamine (XIV) in Et2O , or alternatively reaction of 2-fluoro-4-iodoaniline (XV) with CDI in the presence of Et3N in DMF, followed by condensation with cyclopropylamine (XIV) affords disubstituted urea (XVI). Cyclization of urea (XVI) is treated with malonic acid (XVII) in the presence of AcCl in Ac2O at 60 °C affords the pyrimidine trione (XVIII), which is chlorinated using POCl3 in the presence of PhNMe2 and a catalytic amount of H2O at 90 °C to provide a mixture of 6-chloropyrimidine (XIX) and the corresponding regioisomer. Finally, chloropyrimidine (XIX) is treated with methylamine (XX) in EtOH at 80 °C .
In an alternative procedure, acylation of urea (XVI) with cyanoacetic acid (XXI) by means of MsCl in DMF yields the N-(cyanoacetyl)urea (XXII), which cyclizes in aqueous NaOH at 80 °C to yield the amino-pyrimidine derivative (XXIII). Condensation of amine (XXIII) with dimethylformamide dimethylacetal (XXIV) in DMF affords formamidine (XXV), which is finally reduced using NaBH4 in EtOH/t-BuOH .

合成路线18

Conjugate addition of acrolein (LVIII) to nitromethane in the presence of KOH in MeOH followed by treatment with Na2S2O5 in H2O gives the nitrodisulfonate (LIX), which is hydrolyzed with glyoxylic acid by means of NaHCO3 to yield 4-nitroheptanedial (LX). Compound (LX) is cyclized in the presence of pyrrolidine and PhCOOH in CH2Cl2, providing 5-nitro-1-cyclohexenecarbaldehyde (LXI). Wittig reaction of aldehyde (LXI) with (methoxycarbonylmethylene)triphenylphosphorane (LXII) leads to conjugated ester (LXIII), which is finally saponified with NaOH .
Acid (XXXVII) can be alternatively prepared by Knoevenagel condensation of aldehyde (LXI) with malonic acid (LXIV) .
Hydrolysis of ethylene ketal (XVI) with aqueous p-toluenesulfonic acid gives ketone (LXV), which, without isolation, is converted to oxime (LXVI) by addition of hydroxylamine hydrochloride. Subsequent oxidation of oxime (LXVI) using sodium molybdate and H2O2 leads to compound (XXXVII) .