作者:Johan Hygum Dam、Robert Madsen
DOI:10.1002/ejoc.200900719
日期:2009.9
A synthesis of the antitumour agent pancratistatin is described from piperonal and D-xylose. Piperonal is converted into cinnamyl bromide 11 while methyl 5-iodoribofuranoside 12 is derived from xylose. The allylic bromide and the iodocarbohydrate are combined in a zinc-mediated tandem reaction to afford a highly functionalised 1,7-diene, which is then converted into the corresponding cyclohexene by
描述了从胡椒醛和 D-木糖合成抗肿瘤剂 pancrastatin。胡椒醛转化为肉桂基溴化物 11,而甲基 5-碘代呋喃核糖苷 12 来自木糖。烯丙基溴和碘代碳水化合物在锌介导的串联反应中结合,得到高度官能化的 1,7-二烯,然后通过闭环烯烃复分解转化为相应的环己烯。随后的 Overman 重排、二羟基化和脱保护从两种起始材料中通过总共 25 个步骤提供了天然产物。最长的线性序列来自胡椒醛,分 18 个步骤产生 pancratastatin,总产率为 7.0%。(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)