Synthesis and antitumor screening of novel 3-phenylthiazolo [4,5-d]pyrimidin-2-thione derivatives.

A series of new derivatives of 3-phenylthiazolo[4,5-d]pyrimidine-2-thiones were synthesized by the cyclization of 4-amino-5-alkyl(aryl) carboxamido-2,3-dihydrothiazolo-2-thione with aromatic aldehydes. Amine moieties were substituted in position 7 of the obtained bicyclic compounds. The synthesized compounds were characterized by elemental analysis, IR, 1H-NMR, and 13C-NMR spectral data. Some of the newly synthesized compounds were selected by the U.S. National Cancer Institute for in vitro antitumor screening. The two compounds 3d 7-chloro-5-(4-fluorophenyl)-3-phenyl-4,5-dihydro-3H-thiazolo[4,5-d]pyrinimidine-2-thione and 4i 5-(2-chlorophenyl)-7-(4-fluorobenzylaxnlno)-3-phenyl-4,5-dihydro-3H-thiazolo[4,5-dipyrhflldlfle-2thione proved to be the most active in the present study and their antitumor activities against 60 human tumor cell lines were described.