Synthesis of new 2-(N'-Allylidene-hydrazino)quinazolinones and 2-(4,5-Dihydropyrazolyl)-quinazolinones and their antimicrobial and antifungal activity screening

Novel 2-[N'-(1,3-disubstituted-phenyl)allylidene]hydrazine-3-ethyl-3H- quinazolin-4-one (8) and 2-(3,5-disubstituted-phenyl-4,5-dihydropyrazol- 1-yl)-3-ethyl-3H-quinazolin-4-one (9) compounds have been prepared and tested for antibacterial and antifungal activities. ¹H NMR, ¹³C NMR, elemental analysis and mass spectroscopy methods have been used to identify molecular structures of the newly synthesized compounds. For screening antibacterial and antifungal activities of the new compounds, minimum inhibitory concentration (MIC) values were evaluated against the Staphylococcus aureus, Escherichia. coli, Pseudomonas aeruginosa, Enterococcus faecalis, Candida albicans, Candida parapsilosis and Candida krusei using microdilution broth method. Compounds 8a-8h exhibited the best antibacterial activity against E. faecalis.