Hypervalent iodine mediated synthesis of 1-aryl/hetryl-1,2,4-triazolo[4,3-a] pyridines and 1-aryl/hetryl 5-methyl-1,2,4-triazolo[4,3-a]quinolines as antibacterial agents

Oxidation of 2-pyridyl and 2-quinylhydrazones with iodobenzene diacetate (IBD) in dichloromethane yield 1-aryl/hetryl-1,2,4-trizolo-[4,3-a] pyridines (3a-f) and 1-aryl/hetryl-5-methyl-1,2,4-triazolo[4,3-a] quinolines (6a-f). Seven compounds were tested in vitro for their antibacterial activity. 1-(5'-Nitro-2-furyl)-5-methyl-1,2,4-triazolo[4,3-a]quinoline (6e) was associated with substantially higher antibacterial activity than some commercial antibiotics against Salmonella typhi at MIC i.e. 10 mug mL(-1). (C) 2003 Published by Editions scientifiques et medicales Elsevier SAS.