In vivo Analgesics and in vitro Antioxidants Activity of Newly Synthesized Mannich Bases of Lawsone

1, 4- naphthoquinone (Lawsone) is widely distributed in nature and has been used since ancient times in traditional medicine. Lawsone has been used as a dye, and both its natural form and synthetic derivatives exhibit antifungal, antibacterial, antitumor, Antimalarial, molluscicidal, and antioxidant activity. 1, 4- naphthoquinone (Lawsone) was isolated from the leaves of Lawsonia inermis by using the pH gradient (agitation) and maceration method. A convenient synthesis of 2-substituted amino naphthalene-1, 4-dione (3a-o) has been achieved by reaction of isolated 1, 4- naphthoquinone with substituted aniline in the presence of ethanol and DPPH model is used for the evaluation of the antioxidant activities and in vivo analgesic activity using albino mice morphine-induced hot plate method. The structure of the ultimate analogs has been inveterate on the basis of elemental analysis, IR, ¹H NMR, and mass spectra. All the standards of elemental investigation, IR, ¹H NMR, and mass spectra were initiate to be prominent. The results indicate that synthesized compound 3d having IC50 75.39 ± 4.12mg/ml showed potent antioxidant activity comparable to standard ascorbic acid (IC50 45.54 ± 3.06mg/ml). 3c, 3m, and 3o showed potent analgesic activity comparable to standard nimesulide (100% at 50mg/kg b.w). This reading suggests that leaves of Lawsonia inermis have bioactive compounds for innovative antioxidant and analgesic remedy development.