Abstract
In order to examine the structure-activity relationship the syntheses of some progestagens with the abnormal 13α-configuration have been undertaken. Epimeric 17-ethynyl-17-hydroxy derivatives (II and VII) having Δ4-3-ketone system were prepared from the corresponding Δ5-3β-ols (I and VI) by Oppenauer oxidation, respectively. 17-Acetoxy-13oc-pregn-4-ene-3, 20-diones (V and Xb) were prepared by Jones oxidation from 3β, 17-dihydroxy-13α-pregn-5-en-20-one 17-acetates (IIIc and VIIIc) which were readily available from the 3, 17-diacetates (IIIb and VIIIb) by partial hydrolysis. The occurrence of Dhomo-annulation of 17-hydroxy-13α-pregnen-20-ones (IIIa and Villa) with aluminum isopropoxide has also been described.
