Synthesis, Spectral Properties and Anti-tumor Evaluations of Some Novel 2-substituted- 1,3-Thiazole Derivatives

Reaction of N4-(4-chlorophenyl)-1,3-thiazole-2,4-diamine 1 with ammonium thiocyanate, phenyl isothiocyanate, acetic anhydride, phenacyl bromide, 2-chloro -N- (4-chlorophenyl) acetamide and acetic anhydride / cyanoacetic acid afforded the corresponding N-[ 4-(4-chlorophenyl)amino-1,3-thiazol-2-yl]thiourea 2, N-[4-(4-chlorophenyl)amino-1,3-thiazol-2-yl]-N'-phenylthiourea 3, N-acetyl- N-[4-(4-chlorophenyl)amino-1,3-thiazol-2-yl]acetamide 7,2-(1,3-thiazol-2-ylamino)-1 phenylethanone derivative 8, 2-(1,3-thiazol-2-ylamino)- N-(4-chlorophenyl)acetamide derivative 9 and N-(1,3-thiazol -2-yl)-2-cyanoacetamide derivative 11. Reaction 1 with phenyl isothiocyanate in basic DMF yielded the intermediate potassium salt 14, then treatment of intermediate 14 with α-halocarbonyl compounds such as ethyl chloroacetate and/ or 2-chloro-N-(4-chlorophenyl) acetamide afforded ethyl {N'-(1,3-thiazol-2-yl)-N-phenyl-carbamimidoyl)thio}acetate15 and 2-[(4-chlorophenyl)amino]-2-oxoethyl N'-(1,3-thiazol-2-yl)-N-phenyl-imidothiocarbamate16 respectively. Reaction 1 with 1H-pyrazole-4-carboxaldehyde 17 or 1H-indole-3-carboxaldehyde 18 afforded N2-[(1H-pyrazol-4-yl) methylene]-1,3-thiazole-2,4-diamine19 and N2-[(1H-indol-3-yl)methylene]-1,3-thiazol-2,4-diamine 20 respectively. Structures of the newly synthesized compounds have been confirmed by elemental analysis and spectra data. Some of the newly synthesized compounds were screened in vitro for their anti-tumor activities against human cancer cell line MCF-7.