Chlorination of isothiocyanates. V . 5-imino-1,2,4-thiadiazolidin-3-ones

S-N'- (Chlorocarbonyl)amino]isothiocarbamoyl chlorides (II), obtained from S-chloroisothiocarbamoyl chlorides (I) and isocyanates, react with primary aliphatic and aromatic amines to form the unknown class of 5-imino-1,2,4-thiadiazolidin-3-ones. The structures were confirmed by chemical means and by spectroscopic methods.