Synthesis and cytotoxic activity of certain new arylazothiazole containing compounds

2Amino5arylazo42chlorophenylthiazoles 2ae were prepared by the coupling of aryldiazonium chlorides with 2amino42chlorophenyl thiazole 1. The thioureas 3aewere obtained by condensing the arylazothiazoles 2acwith the appropriate isothiocyanates. Reaction of 2dwith aromatic aldehydes afforded the chalcone analogues 4ac. The pyridone derivatives 5a,bwere synthesized by reacting the ketone 2dwith different aromatic aldehydes, ethyl cyanoacetate and ammonium acetate. On the other hand, 5bwas also prepared by cyclizing 4cwith ethyl cyanoacetate and ammonium acetate. Furthermore, 6chloroimidazo2,lbthiazole 7was obtained from the acid derivative 6b by treatment with POC13. While, the imidazo2,lbthiazolones 9adwere produced by the cyclization of the chloroacetyl derivatives 8adwith DMAPpyridine. Representative examples of the prepared compounds were tested for in vitroantitumor activity against two human tumor cell lines. Some compounds showed activity against brain tumor cell lines.