A new, stereoselective approach to C(7)-alkylated estra-1,3,5(10)-triene derivatives
作者:H. Künzer、M. Thiel、G. Sauer、R. Wiechert
DOI:10.1016/0040-4039(94)88321-1
日期:1994.3
sulfonyl)estra- 1,3,5(10),6-tetraene (4) was prepared as a substrate for conjugate addition of organolithium reagents by a three-step sequence starting from 17β-acetyloxy-3-methoxyestra- 1,3,5(10)-trien-6-one (2). While methyllithium showed only poor face selectivity, higher alkyllithium species (n-BuLi, t-BuLi) preferred to add to the β-face of 4. 7α-Substituted derivatives, on the other hand, were
制备了17β-乙酰氧基-3-甲氧基-6-(苯磺酰基)雌二醇1,3,5(10),6-四烯(4)作为从17β开始的三步法共轭添加有机锂试剂的底物-乙酰氧基-3-甲氧基estra-1,3,5(10)-trien-6-一(2)。尽管甲基锂仅表现出较差的表面选择性,但较高级的烷基锂物种(n-BuLi,t-BuLi)更喜欢添加到4的β面上。另一方面,通过在加成步骤中使用炔基锂试剂立体选择性地产生7α-取代的衍生物。通过常规还原性脱磺酰化方法,可以从烷基化产物中除去C(6)处的苯磺酰基。雌激素受体拮抗剂1的简短合成 介绍了利用这些观察结果。