REACTIONS WITH 2-THIOHYDANTOIN DERIVATIVES - SYNTHESIS OF MANNICH-BASES AND IMIDAZOTHIAZOLE DERIVATIVES

5-Arylidene-2-thiohydantoins (la-c) and S-arylazo-1-phenyl-2-thiohydantoins (7a, b) were condensed with formaldehyde and primary or secondary aromatic amines to give the corresponding Mannich bases (2a-f) and (8a, b) respectively, which could also be converted into the educts (la-c) and (7a, b) by boiling in ethanolic HCI. On treatment of (2a-f), (5a-c) and (8a, b) with an ethereal diazomethane the colourless cyclopropane products (3a-c) and yellow N-methyl substituted compounds (9a, b) were isolated respectively. Alkylation of (2d-f) with methyl iodide and (la-c) with 3-chloropentane-2, 4-dione gave the corresponding 2-alkylmercapto derivatives (5a-c) and (12a-c) respectively, the former of which on hydrolysis by boiling ethanolic HCI afforded the hydantoin derivatives (6a-c). Cyclization of (12a-c) using polyphosphoric acid resulted in the formation of imidazothiazole derivatives (13a-c). The structure of the isolated products were established by elemental analyses and spectral data studies. © 1990 Gordon and Breach Science Publishers, Inc. © 1990, Taylor & Francis Group, LLC. All rights reserved.