盐酸戊乙奎宁在水溶液中的降解机理

THE DEGRADATION MECHANISM OF PENEQUINE HYDROCHLORIDE IN AQUEOUS SOLUTIONS

盐酸戊乙奎宁(Ⅰ)为强效抗胆碱能新药,化学名为3-(2-苯基-2-环戊基-2-羟基-乙氧基)奎宁环烷盐酸盐,结构式如下。其抗胆碱作用、光学纯化合物的合成与分离以及立体化学与构效的关系已有报道。作为该药处方前研究的一部分,本文对Ⅰ在水溶液中的稳定性进行了研究。

Penequine hydrochloride (Ⅰ) is a new potent anticholinergic drug, the degradation mechanism of Ⅰ in aqueous solutions is reported in this paper. Ⅰ is an ethereal compound, stable in neutral and alkaline solutions, but it decomposes in strong acidic solutions. Its main degradation products have been separated and identified by means of TLC, MS, GC/MS and GC/FTIR. With reference to the general degradation rule of ethereal compound and the structure of the degradation products, we deduced that the ether linkage of Ⅰ splits in acidic solutions by the catalysis of hydrogen ion, producing 3- quinuclidinol (DP1) and 1-phenyl- 1-cyclopentyl glycol. The latter turns into 1-phenyl-l-cyclopentyl acetaldehyde through dehydration and rearrangement. In addition, small amounts of other degradation compounds, e. g. benzaldehyde, acetophenone, phenylcyclopentyl ketone, etc. have also been found, but the mechanism remains to be further studied.