New Niacin Derivatives Boosting with Monosaccharide: Synthesis, Structural Characterization, and Biological Evaluation

New niacin derivatives conjugated with monosaccharides were synthesized through a series of reactions and then evaluated in vitro as antimicrobial and antioxidant agents. Briefly, 4bromonicotinic acid was reacted with hydrazine hydrate to give 4-bromonicotinohydrazide in a single step. Next, the derivative obtained was condensed with various monosaccharides via the Schiff base reaction. Biologically, the antioxidant activity of these compounds was investigated by phosphomolybdate test, results obtained in this test revealed encouraging activity for some of synthesized derivatives with good EC₅₀ values compared to ascorbic acid. In addition, the antimicrobial activity of synthesized derivatives showed good inhibition against both C. albicans and E. coli compared to standard drugs.