Facile Synthesis, Characterization of New Quinazolinones with Different Azo Compounds, 1,2,3-Triazole Moieties and Evaluation Their Anti-bacterial Activity.

Abstract

In the present research, a series of some azo compounds (5-9) and 1,2,3-triazoles derived from 2-methyl quinazolin-4(3H)-one were synthesized successfully by stepwise routes includes the following: 3-amino-2-methylquinazolin-4(3H)-one (3) prepared firstly by conversion of 2-aminobenzoic acid into methyl 2-aminobenzoate (1) followed by reaction with acetic anhydride to form methyl -2-acetamidobenzoate (2). The amide then allowed reacting with hydrazine hydrate to give compound (3). Diazotization reaction with sodium nitrite in the presence of hydrochloric acid yield the 3-(chlorodiazenyl)-2-methylquinazolin-4(3H)-one(4). Diazonium salt (4) then enter two different routes. The first route was its conversion into azo compounds (5-9) by reaction with coupling components.The second route included formation of 1,2,3- triazole derivatives by interconversion of compound (4) into azido compound (10) followed by treatment with ethyl acetoacetate, acetyl acetone to give 5-methyl-1-(2-methyl-4-oxoquinazolin-3(4H)-yl)-1H-1,2,3-triazole-4-carboxylic acid (11) and 3-(4-acetyl-5-methyl-1H-1,2,3-triazol-1-yl)-2-methylquinazolin-4(3H)-one (12) in good yield. Newly synthesized derivatives were characterized spectroscopically by FTIR, 13C-NMR and 1H-NMR spectral technique and by determination of their physical properties. Also end time of reactions monitored by thin layer chromatography. The antibacterial potential of synthesized azo compounds, 1,2,3-triazole of methyl quinazolin-4(3H)-one has been tested against the growth of four gram positive and gram negative pathogenic bacterial strains using agar well diffusion method. Ampicillin trihydrate used as reference drug. The results of the antibacterial study showed that compounds (7-9) appeared good activity.