Synthesis of androstane derivatives fused with polyheterocycles at the D ring

An unusual reaction of 16α,17α-epoxypregn-5-en-20-one with 3-amino-5-mercapto-1,2,4-triazole is accompanied by the heterocyclization involving epoxy ring opening and results in a mixture of new androstane derivatives fused with polyheterocycles at the D ring. Such polyheterocycles belong to 3-thia-1,2,8,8b-tetraazaacenaphthylene and 1,2a,7,7b-tetraazacyclopenta[cd]indene-2-thione families incorporating isomeric [1,2,4]triazolopyrimidine systems