Synthetic studies toward potent cytostatic macrolide bryostatin: an expedient synthesis of C1–C10 fragment
作者:J.S. Yadav、S. Aravind、G. Mahesh Kumar、B.V. Subba Reddy
DOI:10.1016/j.tetlet.2012.07.043
日期:2012.11
The stereoselective synthesis of C1–C10 fragment of cytostatic macrolide bryostatin is described. Two of the three chiral centers have been established via the Sharpless kinetic resolution of racemic allylic alcohol 15 followed by regioselective reduction of epoxy alcohol 8 with Red-Al. Diastereoselective Aldol reaction of an aldehyde 7 with methyl isobutyrate affords the corresponding β-hydroxyester
描述了细胞抑制性大环内酯类bryostatin C1-C10片段的立体选择性合成。通过手性外消旋烯丙醇15的Sharpless动力学拆分,然后用Red-Al选择性还原环氧醇8,建立了三个手性中心中的两个。醛7与异丁酸甲酯的非对映选择性Aldol反应得到相应的β-羟基酯23,然后将其通过分子内半缩酮化转化为四氢吡喃环系统3。