It is shown that irradiation of the 20-keto-pregnane derivatives I, XI and XVI leads predominantly to cyclisation between the carbon atoms 18 and 20 with formation of the novel pentacyclic steroid compounds II, XII and XVII. Simultaneously fragmentation reactions occur yielding products of type XIX and XX.
结果表明,辐照20-酮-孕烷衍
生物I,XI和XVI主要导致碳原子18和20之间的环化,并形成了新颖的五环类
固醇化合物II,XII和XVII。同时发生断裂反应,产生XIX和XX型产物。