Synthesis of 6-Substituted 3(H)-Quinazolin-4-Ones and Their Antimicrobial Activity

Three-step synthesis of 6-amino-3(H)-quinazolin-4-ones has been performed. Initially, the condensation of 3(H)-quinazolin-4-one was carried out in the presence of anthranilic acid and formamide in a 1:3 ratio. Then, hydrogen atom in state 6 of the resulting 3(H)-quinazolin-4-one was replaced by nitro group using a nitriding compound and 6-nitro-3(H)-quinazolin-4-one reduction was performed using SnCl2 center dot 2H(2)O as a reducing agent. Acylation reactions were accomplished on the synthesized 6-amino-3(H)-quinazolin-4-one. The structures of synthesized compounds were determined based on their IR and H-1 NMR spectra. The obtained compounds were evaluated for antibacterial and antifungal activities by the agar disk diffusion test. The results indicated that 6-nitro-3(H)-quinazolin-4-one exhibited remarkable antibacterial activity against Bacillus subtilis, Staphylococcus aureus and Escherichia coli bacterial strains.