van Rozendaal E L, Veldhuis H, van Veldhuizen B, van Beek T A, de Groot A, Beusker P H, Scheeren H W
Laboratory of Organic Chemistry, Phytochemical Section, Wageningen University, Dreijenplein 8, 6703 HB Wageningen, The Netherlands.
J Nat Prod. 2000 Feb;63(2):179-81. doi: 10.1021/np990206h.
During the large-scale synthesis of an O-cinnamoyltaxicin I acetonide, an intermediate for the semisynthesis of 7-deoxypaclitaxel derivatives, side-product 3 was formed via a vinylogous retro-aldol reaction and a long-range hydride shift from O-cinnamoyltaxicin I (1) under alkaline reaction conditions. Compound 3 has two hemi-acetal bridges at C-1,C-9 and C-10,C-13. Compound 4 was formed from side-product 3 under acidic reaction conditions and is the first C-13 spiro-taxane described in the literature. This spiro-taxane has two acetal bridges between C-1, C-13 and C-10,C-13.
在大规模合成O-肉桂酰基紫杉素I丙酮化物（一种用于半合成7-脱氧紫杉醇衍生物的中间体）过程中，在碱性反应条件下，副产物3通过烯醇型逆向羟醛缩合反应以及从O-肉桂酰基紫杉素I（1）发生的远程氢化物迁移而形成。化合物3在C-1、C-9和C-10、C-13处有两个半缩醛桥。化合物4在酸性反应条件下由副产物3形成，是文献中描述的首个C-13螺环紫杉烷。这种螺环紫杉烷在C-1、C-13和C-10、C-13之间有两个缩醛桥。
