Aryldiazepinothiophenones 4 were prepared from the reaction of o-phenylenediamines with acetone in the presence of 2-mercaptocarboxylic acids along with thiazolobenzodiazepines 6, thiazolobenzimidazoles 7 and 1, 5-benzodiazepines 5, which were obtained as by- products. The benzodiazepinothiophenones 4a–d and the benzodiazepines 5a–d were also isolated from the reaction of o-phenylenediamines 1a–c with phorone. Structural ...