[Acylhydrazones of 20-keto steroids and their transformations: I. Synthesis and properties of 1'-acyl-substituted 3'-methylandrosteno[16,17-d]pyrazolines].

Acetates of 3beta-hydroxy-3'-methyl-1'(N)-acylandrost-5-eno[16,17-d]pyrazolines bearing monothiooxamide acyl groups were synthesized during the study of approaches to the synthesis of 3'-methylandrosteno[16,17-d]azoles, promising biologically active analogues of 20-keto pregnenanes, and their properties were investigated. The cyclization of delta16-20-thiooxamidohydrazones to the corresponding heterocycles was shown to proceed under rigorous conditions and to depend partially on the nature of the oxamide grouping.