Synthetic approach to pentacyclic quassinoids from communic acids, via ambracetal derivatives
作者:E.J. Alvarez-Manzaneda、J.L. Romera、A.F. Barrero、R. Alvarez-Manzaneda、R. Chahboun、R. Meneses、M. Aparicio
DOI:10.1016/j.tet.2004.11.034
日期:2005.1
Abstract Methyl (8 R ,13 S )-8α,13:13,17-diepoxy-14,15-dinorlabdane-19-oate, easily prepared from communic acids, is a suitable intermediate for synthesizing pentacyclic quassinoids, because it enables the elaboration of the A ring and the further construction of the B–C–D ring system of these terpenoids. The cetal group is stable under the reaction conditions utilized during the elimination of the
摘要 (8 R ,13 S )-8α,13:13,17-diepoxy-14,15-dinorlabdane-19-oate 易于从交流酸中制备,是合成五环类类化合物的合适中间体,因为它可以制备这些萜类化合物的 A 环和 B-C-D 环系统的进一步构建。在消除酯基和在 C-3 上引入羟基期间所用的反应条件下,缩醛基团是稳定的。同时,它能够再生甲基13-oxo-14,15-dinorlabd-8(17)en-19-oate所呈现的甲基酮和环外双键。后一种化合物以前被用于构建这些类类化合物的 B-C-D 环。