Synthesis of benzophenothiazinone derivatives from 2,3,5-trisubstituted-1,4-naphthoquinones with 2-aminothiophenol

The 1-substituted-5H-benzo2,3-a]phenothiazin-5-one, 4-substituted-5H-benzo6,5-a]phenothiazin-5-one and 6-substitutedbenzoa]1,4] benzothiazino3,2-c]phenothiazine derivatives were prepared by the condensation of 5-substituted-2,3-dichloro-1,4-naphthoquinones with 2-aminothiophenol. Reduction, acetylation and dehalogenation of the resulting compounds were carried out and the structures of the products were inferred from comparison with the authentic compound.