Rapid synthesis of 2-cyanobenzothiazole, isothiocyanate and cyanoformanilide derivatives of dapsone

Abstract

New derivatives of the leprostatic drug dapsone are prepared by way of imino-1,2,3-dithiazoles obtained by condensation of aromatic primary bisamines, including dapsone, with 4,5-dichloro-1,2,3-dithiazolium chloride (Appel salt). Reactions, including microwave irradiation, initiated by nucleophilic attack at different sites of the dithiazole ring transform the bisiminodithiazoles into the symmetrical, and some unsymmetrical, title compounds.