Hydrazonoyl halides as precursors for new fused heterocycles of 5α-reductase inhibitors.

A new series of benzo[6,7]cyclohepta[1,2-d]triazolo[4,3-a]pyrimidines 8a-l was synthesized via reaction of heterocyclic thione 4 or its methyl derivatives 10 with hydrazonoyl halides 5a-l. Also, reaction of compound 4 with a mixture of chloroacetic acid and aromatic aldehyde derivatives gave benzo[6,7]cyclohepta[1,2-d]thiazolo[3,2-a]pyrimidin-3-ones 12-14. The microanalyses and spectral data of the synthesized compounds are in full agreement with their molecular structure. All the newly synthesized products were screened against 5α-reductase and showed activities with good ED(50) for all compounds.