Part 7: Synthesis of some new 1,5-benzodiazepines fused with different heterocyclic moieties

3-cyano-1,11-dihydro-4,.5-diphenyl-2-thioxopyrido[2,3-b](1,5)benzodiazepine 2 and 3-(2'-cyano-1'-phenyl-2'-ethanethiocarboxamide)-4-phenyl-1(H)(1,5)benzodiazepin-2-one 3 were prepared via the reaction of 1,3-dihydro-4-phenyl-(1,5)benzodiazepin-2-one 1 with benzylidenecyanothioacetamide. Compound 2 was treated with halo compounds to give the corresponding S-alkylated compounds 4(a-c), which underwent as intramolecular ring closure to thieno[3,2.5,6]pyrido[2,3-b](1,5)benzodiazepines 5(a-c), under PTC conditions. One-pot syntheis of compounds 5(a-c) was achieved via the reaction of compound 2 with the appropriate halo compound under PTC conditions. Compound 1 and 1-ethyl-4-phenyl-(1,5)benzodiazepin-2-one 9 were treated with carbon disulfide or phenylisothiocyanate and active nitrites to afford 4-thioxothiopyrano[4,3-b](1,5)benzodiazepines 8 and 10-14. Treatment of compound 10 with phenylisothiocyanate or acetic anhydride yielded oxazino- and pyrimido(4,5-blthiopyrano-(4',3'-b'](1,5)benzodiazepine 15 and 17. The reaction of compound 1 with elemental sulfur and active nitriles yielded thieno(3,2-b](1,5)benzodiazepines 18-21, respectively.