A Novel Approach to Combretastatins: From trans-Epoxide to CA-4 and Its Dioxolane Derivative
作者:Paolo Lupattelli、Maurizio D'Auria、Nadia Di Blasio、Francesca Lenti
DOI:10.1002/ejoc.200800957
日期:——
The trans-epoxide derivative of Combretastatin A-4 wasstereoselectively prepared in good yield by sulfur ylide mediated epoxidation of silyl-protected isovanillin. From this key intermediate, a formal synthesis of CA-4, by stereoselective deoxygenation and photoisomerization, was achieved. Alternatively, a trans-dioxolane derivative was obtained bystereoselective acetone insertion.(© Wiley-VCH Verlag
Combretastatin A-4 的反式环氧化物衍生物通过硫叶立德介导的甲硅烷基保护异香草醛的环氧化以良好的收率立体选择性地制备。从这个关键中间体,通过立体选择性脱氧和光异构化实现了 CA-4 的正式合成。或者,通过立体选择性丙酮插入获得反式二氧戊环衍生物。 (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)