• Archives of Pharmacal Research
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• v.14 no.4
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• pp.319-324
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• 1991

2,6-Dimethyl-4-(3'-nitrophenyl)-3-methoxylaminocarbonyl-1,4-dihydropyridine-5-carboxylic acid methylester, 3b reacted with 2-cyanoethanol or benzylalcohol to give the corresponding cyanoethylurethane compound 6c in 40.6% yield and benzylurethane compound 6d in 32% yield. The cyanoethylurethane 6c was hydrolized in ethanolic NaOH to give 2,6-dimethyl-4-(3'-nitrophenyl)-1,4-dihydropyridine-3-amino-5-carboxylic acid 5-methyl ester. HCl 8 in 64.8% yield. Another acid hydrolysis of benzylurethane 6d gave 2,6-dimethyl-4-(3'-nitrophenyl)-1,4-dihydropyridine-3-amino-5-carboxylic acid 5-methylester. HBr 11 in 54.7% yield.

• YAKHAK HOEJI
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• v.33 no.5
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• pp.290-295
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• 1989

2,6-Dimethyl-4-(3'-nitrophenyl)-1,4-dihydropyridine-3-carboxylic acid methyl ester (1) was formylated to 2,6-dimethy-4-(3'-nitrophenyl)-5-formyl-1,4-dihydropyridine-3-carboxylic acid methyl ester (2) in 76% yield. At the elevated temperature, 2,6-dimethyl-4-(3'-nitrophenyl)-1,4-dihydropyridine-3,5-dicarboxylic acid 3-monomethyl ester (3) was also converted into compound 2 in 46% yield. The compound 2 was reduced to 2,6-dimethyl-4-(3'-nitrophenyl)-5-hydroxymethyl-1,4-dihydropyridine-3-carboxylic acid methyl ester (4) in 91% yield. Compound 2 was reacted with triethyl phosphonoacetate to give 2,6-dimethyl-4-(3'-nitrophenyl)-5-(2-ethoxycarbonyl ethenyl)-1,4-dihydropyridine-3-carboxylic acid methyl ester (5) in 50% yield. Reaction between compound 2 and amines (methyl amine, ethylamine, methoxylamine, hydroxyl amine, phenyl hydrazine and 1-amino-4-methyl piperazine) gave six schiff bases 7a, 7b, 7c, 7e, 7f in 81%, 91%, 82%, 81%, 50% and 84% yield, respectively.