Procedure for obtaining asymmetric diesters delacido 1,4-dihydro-2,6-dimethyl-4- (3-nitrophenyl) - pyridine-3,5-dicarboxylic acid

摘要

Asymmetric diesters of 1,4-dihydro 2,6-dimethyl 4-(3-nitro phenyl)pyridine 3,5-dicarboxylic acid of formula (I), in which R1 and R2 are alkyl or alkoxy-alkyl are made by hydrolysis-esterification of a cpd. of formula (II) with a cpd. of formula R1OH (III) under acid conditions obtained by inorganic acids, e.g. H2SO4, HCl, HBr or H3PO4. The prod. is isolated by conventional methods.