Preparation of 1,4-dihydropyridine derivative

Abstract

Abstract PURPOSE: To prepare nicardipine by reacting one of ester groups of 2,6- diomethyl-4-(3-nitrophenyl)-1,4-dihydropyridine-3,5-dicarboxylic acid dimethyl ester, with N-benzyl-N-methylaminoethanolate. CONSTITUTION: A compound of formula I is reacted with a compound of formula II (M is a metal atom, particularly Na, K preferred), at 30-120°C for 2-70 hours to form a compound of formula III through the exchange of the ester. The compound of the formula II can be added as it is, but it can be effectively prepared in situ from N-benzyl-N-methylaminoethanol in the presence of a strong base such as Na, NaOH, KOCH 3 or the like. The reaction is performed in a solvent such as THF, toluene, dioxane or the like. The compound of the formula I is prepared by the reaction of 3-nitrobenzaldehyde, methyl acetoacetate, and ammonia. By the above-mentioned process, the compound of the formula III can be prepared with high purity and high yield. COPYRIGHT: (C)1992,JPO

Inventors

• 👤 Arudo Beri
• 👤 ベリ，アルド
• 👤 Giovanni Villa
• 👤 ヴィラ，ジョバンニ
• 👤 Claudio Cremonessi
• 👤 クレモネッシ，クラウディオ

Bibliographic Details