A novel and efficient synthesis of 3-iodo substituted 1,8-naphthyridines by electrophilic cyclization of 2-amino nicotinaldehyde and their antimicrobial activity

Abstract

Synthesis of substituted 1,8-naphthyridines based on 2-aminonicotinaldehyde under mild conditions is studied. Out of three electrophilic iodine sources (I₂, NIS, and ICl) studied, I₂ was determined to act most efficiently in the process. High overall yields were achieved for aliphatic substitution at the reaction center. All compounds were evaluated for antibacterial activity (Staphylococus aureus, Bacillus subtilis, Escherichia coli, and Klebsiella pneumonia) and anti-fungi activity (Aspergillus flavus and Fusarium oxysporum).