2 -Nitrobenzylideneacetoacetic acid methyl ester

Nitrobenzylideneacetoacetic acid methyl ester p-Aminocrotonic acid isopropyl ester... 

Boiling a solution of 12.7 g of 2 -nitrobenzylideneacetoacetic acid methyl ester and 7.1 g of p-amino-crotonic acid isopropyl ester in 50 ml of methanol for 10 hours yielded 2,6-dimethyl-4-(2 -nitrophenyl)-l,4-dihydropyridine-3,5-dicarboxylic acid 3-methyl ester-5-isopropyl ester of melting point 174°C (from ethanol). Yield 48% of theory. 

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