Abstract
The synthesis of 3α,20β-dihydroxy-9-oxo-9,12-seco-12-pregnanoic acid (XV) and some of its derivatives, from 3α,12α-diacetoxy-20-oxopregnane, is described. The fission of ring C was achieved by ozonolysis of a 9,11-unsaturated 12-ketones. In the course of this work evidence was found that the rearrangement of certain 11-hydroxy-12-ketones to 12β-hydroxy-11-ketones, under the influence of alkali, can occur in high yield, even at room temperature.