Ultrasound Assisted Synthesis and Antimicrobial Evaluation of Novel Thiophene Chalcone Derivatives

Abstract

A series of 10 novel 5-bromo-thiophene containing chalcone derivatives (SN1-SN10) were synthesized under ultrasonic irradiation in the presence of lithium hydroxide monohydrate (LiOH.H2O) as a catalyst, which provided the products in good yields after short reaction times under mild conditions. All the synthesized compounds were characterized by spectral data and evaluated for in vitro antibacterial and antifungal activities. Antibacterial and antifungal activities were tested using the agar diffusion method. From the screening studies it was observed that most of the compounds have shown moderate antibacterial and antifungal activities at 500 µg/mL and 100 μg/mL concentrations respectively. Test compounds SN4, SN6, SN7 and SN8 exhibited promising antibacterial activity at 500 µg/mL concentration against the standard ciprofloxacin, whereas all the tested compounds are less active against Candida albicans and moderately active against Aspergillus niger when compared to that of the standard fluconazole.