RESUMEN
In this present study seven novel thiazole derivatives (PM3-PM9) were synthesized by cyclization of key intermediate thiosemicarbazone (PM2), derived from 4-piperidone (PM1). The parent 4-piperidone was synthesized by Mannich condensation reaction with good yield (89%). All the derivatives were characterized by UV, IR, 1HNMR and mass spectral analysis. All the synthesized products were screened for their in vivo analgesic activities. Most of the tested compounds exhibited potential to reduce pain and some of them showed good analgesic properties. Thiosemicarbazone derivative showed most significant activity (p-value 0.01). All the thiazole derivatives exhibited dose dependent mild to good analgesic activities. Among thiazole derivatives, chloro and nitro substituted compounds (PM3, PM4, and PM5) showed highest analgesic activities.