## 4 Discussion  
From the results of this research, it was found that, although the \({}^{13}\)C NMR spectrum has not been measured yet, the results of the three kinds of spectra of IR, MS, and \({}^{1}\)H-NMR were strong enough for the authors to confirm that the substances created from this synthesis process matched the predictions. Therefore, other researchers can utilize this process to synthesize the 4(3\(H\))-quinazolinone derivatives mentioned in the title on a larger scale.  
In particular, in line with the goals of this study, 14 substances were revealed to possess antibacterial and antifungal effects, in which there were five potential derivatives with good MICs. Hence, other researchers could expand our pilot study to other bacterial or fungal strains to obtain more data. By the results of this study, the derivatives **3a-s** showed different effects on bacteria and fungi because of the main difference of R1 or R2 in the 2-disubstitutedmethyl functional group of 4(3\(H\))-quinazolinone derivatives, in which we should focus on five potential derivatives (**3f**, **3j**, **3p**, **3r**, **3s**). Among them, there were four derivatives containing R1 = R2 (**3f**: R1 = R2 = Thi; **3**j**: R1 = R2 = Tri; **3**p**: R1 = R2 = Tri; **3**s**: R1 = R2 = Imi), which means the C in the 2-disubstitutedmethyl functional group is not the C* (asymmetric carbon atom), and there is no C* in these compounds, so we except the chirality effects to five potential derivatives in this study.  
Additionally, there are some main ways that the antibiotics act on bacteria: They inhibit DNA synthesis, RNA synthesis, cell wall synthesis, and protein synthesis [19], meaning that the antibiotics must cross the bacterial cell membrane to achieve such inhibition. The boundary of the cell membranes behaves as a lipid-like barrier against the passage of many foreign organic compounds. Numerous drugs diffuse across the cell boundary due to the fact that they are lipid soluble, and the rates of transfer are, in general, related to the relative lipid/water partition coefficients of the molecules and the almost lipid-insoluble or ionized forms of drugs that can difficultly diffuse across these boundaries [20]. In addition, some studies have confirmed the correlation of bacterial cell membranes with antimicrobial agents, in which the lipid composition of the bacterial membrane could affect the effect of antibacterial agents, indicating the importance of the lipid composition of bacterial membranes in determining the susceptibility of an organism to the action of certain antimicrobial agents [21]. Based on the results of this study, most R1 = R2 = heterocyclic compounds (**3f**: R1 = R2 = Thi; **3j**: R1 = R2 = Tri; **3p**: R1 = R2 = Tri; **3s**: R1 = R2 = Tri) had better antibacterial effects than R1 = halogen compounds. Because R1 = R2 = heterocyclic compounds were well dissolved in the lipid medium, their permeability through cell membranes was better than that of R1 = halogen compounds. This important property helps active substances penetrate fungal and bacterial cells, leading to the enhancement of their antibacterial and antifungal effects, in which the difference between **3f** and other substances is the thiazole heterocyclic, consisting of 1 N and 1 S. Thus, it can be preliminarily recognized that different heterocyclic elements are able to increase the capacity of cell membrane permeability. Therefore, the antibacterial and antifungal effects can be optimized in further research by focusing on substance **3f** or by increasing the solubility of potential substances in lipids by using other heterocycles as agent replacements, with particular attention paid to heterocycles containing N and S.