Synthesis and biological evaluation of new 3-substituted indole derivatives as potential anti-inflammatory and analgesic agents Original Research Article

Treatment of 3-cyanoacetyl indole 1 with the diazonium salts of 3-phenyl-5-aminopyrazole and 2-aminobenzimidazole afforded the corresponding hydrazones 4 and 5. 3-Cyanoacetyl indole reacted with phenylisothiocyanate to give the corresponding thioacetanilide derivative 7. Treatment of 7 with hydrazonoyl chlorides afforded the corresponding 1,3,4-thiadiazole derivatives 8a–f and 9. Also, the thioacetanilide reacted with α-haloketones to afford thiophene derivatives 10a,b (tenidap analogues), or thiazolidin-4-one derivative 11. The newly synthesized compounds were found to possess potential anti-inflammatory and analgesic activities.