mercaptoacetic acid followed by acid-catalyzed cyclization, and by the reaction of ammonia or primary amines with carbon disulfide and chloroacetic acid in the presence of bases. The condensation of aromatic aldehydes or ketones at the nucleophilic C-5 active methylene of rhodanines has been performed using tetra(n-butyl)ammonium hydroxide, under microwave in the presence of tetra(n-butyl)ammoniumbromide, 1-