Abstract

A NEW APPROACH FOR THE SYNTHESIS OF 6-ARYL-5,6-DIHYDRO BENZIMIDAZO[1,2-C]QUINAZOLINE DERIVATIVES AND ITS BIOLOGICAL STUDY

Joshi P.P* and Shirodkar S.G

ABSTRACT

Aromatic amines (1) were treated with chloral hydrate and hydroxylaminehydrochloride to obtain substituted isatins (2), which were converted into substituted isatoic anhydrides (3) using acetic acid. (3) were treated with o-phenylenediamine to obtain substituted 2-(2-aminophenyl) benzimidazoles (4).A series of 6-aryl 5,6-dihydrobenzimidazo[1,2c]quinazolines 7(a-t) were synthesized by the condensation of (4) with different aryl aldehydes. The structures of the products were confirmed from 1HNMR, 13CMR, IR and LCMS spectra. The antimicrobial activities of all 6-aryl-5,6 -dihydrobenzimidazo [1,2-c]quinazolines against Gram-positive (S.aureus,), and Gram-negative bacteria (E.Coli.) and fungal strains (, C. albicans) were evaluated. Compound s Showed promising activity whereas the moderate activity was observed for b,f,g,n,r against S.aureus . Best activity was observed for c,f,j and medium activity for g,k,o,s against E.Coli. Compounds d,e,h,i,l,p,q,t were found to posses antifungal activity against C. albicans.

Keywords: 2-(2-amino phenyl) benzimidazoles, aromatic aldehydes, isatin, isatoic anhydride.