Synthesis of Some Mannich Bases of 6-Substituted-2-Aminobenzothiazole as Analgesic

Eighteen new Mannich bases were synthesized by condensation of equimolar quantities of corresponding 6-substituted-2-aminobenzothizole derivatives with 4-substututed-acetophenones in presence of formaldehyde and concentrated hydrochloric acid. The purity and homogeneity of the synthesized compounds was routinely checked by TLC using solvent systems Benzene: methanol (50:50 v/v). All the synthesized compounds were characterized by FT-IR, 1H-NMR, 13C-NMR and Mass spectroscopy. Out of the synthesized compounds, few compounds were selected randomly and were screened for analgesic activity. Few compounds exhibit excellent activities as compared to the standard drugs.