A process of preparing a stable parenteral solution of a 1,4-dihydropyridine salt, such as nicardipine hydrochloride, in an acidic aqueous medium. The presence of L-arginine in the solution enhances the solubility of the salt, which is poorly soluble in water.
An aqueous, injectable isotonic solution at pH about 3.5-3.6 consists essentially of nicardipine hydrochloride, L-arginine, and a sugar alcohol.
An improved single pot manufacturing process for obtaining unsymmetrical 1,4-dihydropyridines by using more than one mole equivalent of aldehyde with respect to the other reactants (amino crotonate and acetoacetate ester). The reaction can be conducted in a solvent present at 20 times the amount of any one component.
A process for changing one polymorph of nicardipine hydrochloride (Form A) into another (Form B), and a separate process for the reverse (Form B into Form A).
一种制备1,4-
二氢吡啶盐(如
盐酸尼卡地平)的稳定无菌溶液的工艺,该工艺在酸性
水介质中进行。溶液中存在
L-精氨酸,可增强盐的溶解度,而盐在
水中溶解度较差。该无菌溶液为
水溶性、注射用的等渗溶液,pH值约为3.5-3.6,主要由
盐酸尼卡地平、
L-精氨酸和糖醇组成。
一种改进的单锅制造工艺,用于通过使用超过其他反应物(
氨基
丙烯酸酯和
乙酰乙酸酯)的摩尔当量的
醛类来获得非对称的1,4-
二氢吡啶。该反应可以在溶剂中进行,溶剂的量为任何一个组分的20倍。
一种将
尼卡地平盐酸的一种多晶形式(A型)转变为另一种多晶形式(B型)的工艺,以及将B型转变为A型的单独工艺。