Journal article Open Access
Manmohan Gupta, Dr Alok Pal Jain*, Mr. Govind Nagar
Objective: The objective of the paper is synthesis and characterization of new 4(3H)- quinazolinone derivative based on styryl moieties and evaluate them for the antimicrobial activity.
Material and methods: The derivatives have been synthesized by the three steps process, in first step 2-methyl-4H-3,1-benzoxazin-4-one compounds was synthesized, in step 2, 2-methyl-3-peptido quinazolin-4-(3H)-ones compound was synthesized and in last step, 2-styryl-3-peptido quinazolin-4-(3H) ones compound have been synthesized by the reaction of synthesized compound of step 2, with different substituted aldehyde to from the final compounds. Total Sixteen compounds have been synthesized and characterized by physicochemical and spectral analysis. The final compounds (QP-1 to QP-16) have been evaluated for anti-microbial activity i.e., antibacterial and antifungal activity by agar based disk diffusion method.
Result and Discussion: The IR spectrum of the final compound QP-1 to QP16 have shown the IR spectrum with characteristics peak at 3442,57 (N-H str.); 1702.33 (C=O str., amide); 1457.55 (C=N str.); 1368.32 (N-O str.); 1565.22 (N=O str.); 852.22 (C-Cl); 1015.32 (C-Br); 1102.22 (C-F). The 1HNMR spectrum of the compound QP-1 to QP16 have shown the characteristics peak at 7.48-8.02 (4H, 1-benzene); 8.15 (1H, s ethylene); 6.66 (1H, s, ethylene), 1.46 (3H, s, methylene); 2.85 (1H, s, methine), 3.50 (3H, s, methyl), 4.62 (1H, s, methine). The Data of antibacterial activity against the gram-positive bacterial strains suggested that compound QP-1, QP-4, QP-6, QP-9, QP12 have shown best activity against gram positive bacteria. The Data of antibacterial activity against the gram-negative bacterial strains (Escherichia Coli, Klebsiella Penumoniae) suggested that among substituted quinazolinone derivatives, compound QP-1, QP-4, QP-6, QP-9, QP12 have shown best activity against gram positive bacteria. The compounds possessed the halogens on the aromatic ring reveals the positive contribution of electron withdrawing groups to the antibacterial and antifungal activity. Presence of electronegative group (Cl, NO2) is required for the potent antimicrobial activity.
Keywords: antimicrobial activity, quinazolinone, peptides, disk diffusion method, antibacterial, antifungal