A chemical acyl migration equilibrium between 12β-hydroxyl and 20-hydroxyl groups was found to depend on the C-17 and C-20 configurations in C/D-cis-polyoxypregnane derivatives. In the case of 20S derivatives with a 17α-side chain, the equilibrium mixture was separated to afford 12β-ester compound and 20S-ester compound. On the other hand, separation of the equilibrium mixture of the 20R compound with a 17α-side chain was difficult, since the 20-ester compound changed to an equilibrium mixture at room temperature. In both 20S and 20R compounds having a 17β-side chain, acyl migration was not observed, and the starting material were recovered.
研究发现,12β-羟基和20-羟基之间的
化学酰基迁移平衡取决于C/D-顺式聚氧孕烷衍
生物中的C-17和C-20构型。对于具有17α侧链的20S衍
生物,平衡混合物分离后得到12β-
酯类化合物和20S-
酯类化合物。另一方面,具有17α侧链的20R化合物的平衡混合物分离比较困难,因为20-
酯类化合物在室温下会转变为平衡混合物。在具有17β侧链的20S和20R化合物中,未观察到酰基迁移,并且原料得以回收。