Selenium heterocycles 1: synthesis and antibacterial activity of some new 1,2,3thia and 1,2,3-selenadiazole containing sulfonamides

4-acetyl sulfonamide derivatives [I] were smoothly condensed with semicarbazide to produce the corresponding semicarbazones [II]. The latter [II] were when either oxidized with selenium dioxide in acetic acid to give 4-[substituted benzene sulfonamido-4-yl]-1,2,3- selenadiazoles [III] or react with thionyl chloride to give 4- [substituted benzene sulfonamido-4-yl]-1,2,3-thiadiazoles [IV]. The constitution of some of the prepared products is discussed in the light of their infrared and microanalysis data. The biological activities of some of these compounds were tested