Structure-reactivity study of O-tosyl Cinchona alkaloids in their new synthesis and in hydrolysis to 9-epibases. Unexpected formation of cinchonicine enol tosylate accelerated by microwave activation
作者:Teodozja M. Lipińska、Katarzyna Piechocka、Monika Denisiuk、Beata Chmiel、Agnieszka Skórska-Stania
DOI:10.3998/ark.5550190.0013.625
日期:——
O-tosyl derivative, decreases in the following order: quinine, quinidine, cinchonidine and cinchon ine. The same decreasing order has been noticed for the hydrolysis rate of the appropriate tosylates to 9-epibases. Difficult conversion of O-tosylcinchonine in the hydrolytic medium of aqueous tartaric acid gives 9-epicinchonine together with parallel formation of cinchonicine en ol tosylate. The latter
已发现天然金鸡纳生物碱 O-甲苯磺酰化的新方法是一种以 Bu 3N 作为催化剂的双相过程。将四种生物碱中的每一种转化为邻甲苯磺酰衍生物所必需的甲苯磺酰氯的优化过量按以下顺序减少:奎宁、奎尼丁、辛可尼丁和辛可宁。已注意到合适的甲苯磺酸盐水解为 9-表碱基的水解速率具有相同的递减顺序。O-tosylcinchonine 在酒石酸的水解介质中的困难转化得到 9-epicinchonine,同时平行形成 cinchonicine en ol tosylate。当辛可宁和甲苯磺酸辛可尼丁在受控微波加热下在水杨酸存在下反应时,主要获得后一种产物。根据新烯烃产物的 X 射线结构,