Synthesis and antimicrobial activity of new Schiff bases containing coumarin moiety and their spectral characterization
V. S. V. Satyanarayana, P. Sreevani, Amaravadi Sivakumar, and V. Vijayakumar*
Chemistry Division, School of Science and Humanities, VIT University, Vellore-632014, India
E-mail:
[email protected]
Abstract
New Schiff base 2-[(4-Methyl-2-oxo-2H-chromen-7-yl)oxy]-N'-(substitutedmethylene)aceto hydrazides (4a-p) were synthesized by the condensation of aryl/hetero aromatic aldehydes with 2-[(4-methyl-2-oxo-2H-chromen-7-yl)oxy]acetohydrazide under conventional and microwave conditions and characterized through IR, 1H NMR and Mass spectral data. The synthesized compounds have been screened for antimicrobial activity.
Keywords: 2-[(4-Methyl-2-oxo-2H-chromen-7-yl)oxy]-N'-(substitutedmethylene)acetohydrazi- des, conventional method, microwave-irradiation, schiff base, spectral data, antimicrobial analysis
Introduction
Azomethine group (–C=N–) containing compounds typically known as Schiff bases have been synthesized by the condensation of primary amines with active carbonyls. Schiff bases form a significant class of compounds in medicinal and pharmaceutical chemistry with several biological applications that include antibacterial,1-6 antifungal3-6 and antitumor activity.7-8 They have been studied extensively as a class of ligands9-11 and are known to coordinate with metal ions through the azomethine nitrogen atom.
Schiff base complexes play a vital role in designing metal complexes related to synthetic and natural oxygen carriers.12 Metal complexes make these compounds effective as stereospecific catalysts towards oxidation, reduction, hydrolysis, biological activity and other transformations of organic and inorganic chemistry.13 In organic compounds the presence of –C=N– along with other functional groups form more stable complexes compared to compounds with only –C=N– coordinating moiety.
Similarly coumarin derivatives have been of great interest because of their role in natural and synthetic organic chemistry. Many products which contain a coumarin subunit exhibit biological activity such as molluscicides,14 anthelmintic, hypnotic, insecticidal15 activity and some are serving as anticoagulant agents16 and fluorescent brighteners. So coumarins containing a Schiff base are expected to have enhanced antitumor and other biological activities. It is well
