Antibacterial and antimycobacterial activities of 2,3-disubstituted quinazolin-4-ones

About author
R.V. Sheorey¹, A. Thangathiruppathy², V. Alagarsamy³*
¹Research Scholar, Department of Pharmacy, Karpagam University, Eachanari Post, Coimbatore–641021, India.
²Department of Pharmacology, SB College of Pharmacy, Sivakasi–626130, TN, India
³Medicinal Chemistry Research Laboratory, MNR College of Pharmacy, Sangareddy, Gr. Hyderabad-502294, A.P., India.

Abstract
A variety of novel 3-proyl-2-substituted amino-quinazolin-4(3H)-ones were synthesized from 3-proyl-2-hydrazino quinazolin-4(3H)-one with a variety of aldehydes and ketones. When tested for their in vitro antitubercular activity using H₃₇RV strain on Middle brook 7H11 agar slants with OADC growth supplement, all the test compounds inhibited the growth of Mycobacterium tuberculosis at micro gram concentration. Among the test compounds, 2-(N-(4-chloro-benzylidene-hydrazino)-3-propyl-3H-quinazolin-4-one (SR6) and 2-(N-(4-nitro-benzylidene-hydrazino))-3-propyl-3H-quinazolin-4-one (SR7) are found to be the most active compounds against M.tuberculosis with the MIC of 6µg/ml. The title compounds are also screened for the antimicrobial activity against some other gram positive and gram negative bacteria by agar dilution method. Compounds SR6 and SR7 showed the most potent activity (MIC in the range of 32-63 µg/ml) against the tested bacteria (Compound SR6 inhibited the growth of P.aeruginosa, S.typhi and E.coli at the MIC of 32 µg/ml and SR7 inhibited the growth of  K.pneumoniae, B.subtilis and P.aeruginosa  at the MIC of 32 µg/ml).
Key words: Antitubercular, Quinazolinone; Anti-bacterial; M. tuberculosis