| 摘要 |
A process for the preparation of 1,4-dihydropyridines of general formula (I) or acid addition salts thereof, comprising the steps of reacting an acetal of general formula (II) with R<5>ONH2 or an acid addition salt thereof, so as to provide an oxime of general formula (III) in which formulae R<1> each, independently, represents H, Cl or CF3, R<2> represents H, C1-C5 alkyl, C3-C6 cycloalkyl or aralkyl, n is 1 or 2, R<3> and R<4>, which may be the same or different, represents C1-C5 alkyl, C3-C6 cycloalkyl, aralkyl or together represent -(CH2)m-, wherein m is 2 or 3, and R<5> represents H, C1-C5 alkyl, C3-C6 cycloalkyl or aralkyl, and reducing the formed oxime of formula (III) so as to provide a 1,4-dihydropyridine of formula (I), and, if desired, converting a compound of formula (I) obtained as the free base into a pharmaceutically acceptable acid addition salt thereof or vice versa, and novel intermediates of the formulae (II) and (III) are described. |
