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

Abstract

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.