SYNTHESIS, CHARACTERIZATION AND ANTIBACTERIAL EVALUATION OF FEW 2, 3-SUBSTITUTED QUINOXALINES

Abstract

ABSTRACT The quinoxaline derivatives ( i-v ) were synthesized through cyclization-oxidation of α- bromo carbonyl compounds with o-phenyl diamines ( 7a and 10a ) and further coupling at 6-position via Suzuki reaction using PdCl 2 (dppf).DCM, ter. BuNH 2 , Na 2 CO 3 in IPA, H 2 O refluxed for 16 h. As the results of antibacterial screening tests done by paper disc method, quinoxaline derivatives ( i ) and ( v ) revealed significant inhibition zone on Bacillus spericus and quinoxaline derivatives ( iii ) and ( v ) on Escherichia coli cultures. Key words: Quinoxaline, Suzuki Coupling, microwave, Bacillus spericus , Escherichia colie-mail: j_c_reddy@rediffmail.com; som16@rediffmail.com* INTRODUCTION Quinoxaline derivatives are an important class of nitrogen containing heterocyclic in medicinal chemistry, have been reported to show biological, including antibacterial activity 1 . For example, quinoxaline is a part of various antibiotics such as echinomycin, levomycin, and actinoleutin that are known to inhibit growth of gram positive bacteria