Synthesis and antimicrobial activities of some new thiazole and pyrazole derivatives based on 4,5,6,7-tetrahydrobenzothiophene moiety.
2-(5-oxothiazolidinone)-cyanoacetamido derivative 3 was prepared in two steps by reaction of 2-(2-cyano-acetylamino)-4,5,6,7-tetrahydro-benzo[b]thiophene-3-carboxamide (1) with phenyl isothiocyanate and chloroacetyl chloride, which diazocoupled with p-tolyldiazonium chloride in pyridine to afford the corresponding hydrazono derivative 4. Also, condensation of 3 with p-anisaldehyde gave the corresponding arylidine derivative 5. Treatment of 2 with dimethyl sulfate afforded the ketene N,S-acetal 9 which give 5-amino pyrazole derivative 10 upon treatment with hydrazine hydrate. Compound 10 was used as key intermediate for synthesis of pyrazolo[5,1-c][1,2,4]triazine 13a, b, pyrazolo[5,1-a]pyrimidine 14-17 and pyrolo pyrazole 18 derivatives. Finally, condensation of 1 with DMF-DMA afforded the corresponding acryloamide derivative 19, which afforded the corresponding pyrazole derivative 20 upon heating with hydrazine hydrate. All new synthesized compounds were evaluated as antimicrobial agents; some of them exhibited promising activities.
Gouda
M A
MA
Chemistry Department, Faculty of Science, Mansoura University, El-Gomhoria Street, Mansoura 35516, Egypt. dr_mostafa_chem@yahoo.com
Berghot
M A
MA
Abd El-Ghani
Ghada E
GE
Khalil
A M
AM
D000890:Anti-Infective Agents / Q000138:chemical synthesis* / Q000494:pharmacology*; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D011720:Pyrazoles / Q000138:chemical synthesis / Q000494:pharmacology; D013844:Thiazoles / Q000138:chemical synthesis* / Q000494:pharmacology*
D000890:Anti-Infective Agents; D011720:Pyrazoles; D013844:Thiazoles