Synthesis, characterization, anti-inflammatory and in vitro antibacterial activity of some ()-1-Aryl-6,7-dichloroisochromans

Abstract

The present work reports the synthesis of some novel isochromans as antibacterial which additionally possess anti-inflammatory potential to find a therapeutic agent which can be employed to cure bacterial infection as well as the inflammation caused by bacterial infection. Synthesis of some 1-aryl - 6,7-dichloroisochromans (3a-g) was carried out by condensation of 2-(3,4-dimethoxyphenyl)ethanol with a variety of aromatic aldehydes via an acid catalyzed oxa-Pictet-Spengler reaction under microwave irradiation. The structures of the synthesized compounds were assigned on the basis of FT-IR, 1 H NMR, 13 C NMR and mass spectroscopic data. The isochromans (3a-g) were screened for antibacterial activity against ten different bacterial strains using seven Gram-positive and three Gram-negative bacteria. The isochromans (3a-g) were found to exhibit good to excellent antimicrobial activity compared to levofloxacin used as positive control. Antibacterial activity results shows that most of these isochromans are more active against gram negative bacteria as compared to gram positive bacteria. The in vivo anti-inflammatory activity of the synthesized compounds was also evaluated using the carrageenan-induced hind paw edema method and was compared with that of ibuprofen. The newly synthesized isochromans (3c) , (3e) and (3f) exhibited promising anti-inflammatory activity.