| 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.
|
