作者:James R. Bull、Clarissa Hoadley、Pia G. Mountford、Lynne M. Steer                                    
                                    
                                        DOI:10.1039/a606242c
                                    
                                    
                                        日期:——
                                    
                                    Stereocontrolled syntheses of the 14α,17α-propano and
 14β,17β-propano analogues of estradiol are described, together
 with those of numerous derivatives in which additional functionality is
 incorporated into the bridged system. Intramolecular aldol condensation
 of
 17β-acetoxy-3-methoxy-20-oxo-19-nor-17α
 -pregna-1,3,5(10)-triene-14-carbaldehyde 1 furnishes
 3-methoxy-171-oxo-14,17α-prop-172
 -enoestra-1,3,5(10)-trien-17β-yl acetate 2, which is transformed
 into 14,17α-propanoestra-1,3,5(10)-triene-3,17β-diol 17. In
 the first of two synthetic approaches to the 14β,17β-propano
 series, cycloaddition of methyl propiolate to
 3-methoxyestra-1,3,5(10),14,16-pentaen-17-yl acetate 25 gives a
 14,17-bridged intermediate 26, in which the latent propyne equivalency
 of the dienophile is elaborated through selective functional group
 transformations to give
 17-acetoxy-3-methoxy-20-oxo-19-nor-14β
 -pregna-1,3,5(10)-triene-14-carbaldehyde 50 and the derived product 52
 of intramolecular aldol condensation. The second approach entails
 regioselective functionalisation of
 14-allyl-3-methoxy-14β-estra-1,3,5(10)-trien-17-one 54 at
 C-2′ or C-3′ to give intermediates for intramolecular
 closure between the chain terminus and C-17, leading to
 14,17β-propano-14β-estra-1,3,5(10)-triene-3,17α-diol 64.
 The results of competitive binding assays of the hormone analogues 17
 and 64 toward the estradiol receptor are reported, and compared with
 those of bridge-functionalised derivatives.
                                    介绍了 14α,17α-
丙酸和 14β,17β-
丙酸雌二
醇类似物的立体控制合成,以及在桥接体系中加入额外官能团的多种衍
生物的合成。17β-acetoxy-3-methoxy-20-oxo-19-nor-17α -pregna-1,3,5(10)-triene-14-carbaldehyde 1 分子内醛缩合生成 3-methoxy-171-oxo-14,17α-prop-172 -enoestra-1,3,5(10)-trien-17β-yl acetate 2,进而转化为 14,17α-propanoestra-1,3,5(10)-triene-3,17β-diol 17。在 14β,17β-
丙醇系列的两种合成方法中,第一种是将
丙炔酸甲酯与 3-甲氧基
雌甾-1,3,5(10),14,16-
戊烯-17-基
乙酸酯 25 环加成,得到 14,17 桥接的中间体 26、其中,通过选择性官能团转化,亲二烯的潜在
丙炔当量得到 17-乙酰氧基-3-甲氧基-20-氧代-19-去甲-14β-孕甾-1,3,5(10)-
三烯-14-
甲醛 50 和分子内醛醇缩合的衍生产物 52。第二种方法是对 14-烯丙基-3-甲氧基-14β-
雌甾-1,3,5(10)-
三烯-17-酮 54 在 C-2′ 或 C-3′ 进行区域选择性官能化,从而在链末端和 C-17 之间产生分子内闭合的中间产物,最终得到 14,17β-丙氧基-14β-
雌甾-1,3,5(10)-
三烯-3,17α
-二醇 64。
 报告了激素类似物 17 和 64 与
雌二醇受体的竞争性结合试验结果,并与桥功能化衍
生物的结果进行了比较。