Synthesis and Characterization of Some New 2,3-Disubstituted Quinazolin-4(3H)-one Compounds, Investigation of Urease, and AChE Inhibition Properties, Molecular, and Docking Study

Objective: Novel 2,3-disubstituted 4-oxoquinazoline-3(4H) derivatives containing oxadiazole, thiazolidinone ring, the 4-oxoquinazoline-3(4H) Schiff bases, and carbothioamide structure were synthesized. All the synthesized compounds’ urease and acetylcholinesterase enzyme inhibitions were evaluated in vitro. Methods: The chemical structures of the synthesized compounds were confirmed using IR, ¹H, and ¹³C NMR spectral methods. For all newly synthesized compounds, the urease enzyme inhibition activity was measured using the Weatherburn method, and the acetylcholinesterase enzyme inhibition activity was measured using the Ellman method with slight modifications. Results and Discussion: All newly synthesized compounds showed urease enzyme inhibition in the range of IC₅₀ = 11.00 ± 0.10 to 17.45 ± 0.25 µg/mL compared to standard thiourea (IC₅₀ = 15.75 ± 0.25 µg/mL). Among the synthesized compounds, quinazolinone containing oxadiazole ring (IVa–IVd) and thiosemicarbazide structure (IXa–IXd) showed the most inhibition. Most of the synthesized compounds exhibited good inhibitory activities against acetylcholinesterase compared to the standard inhibitor Galantamine (IC₅₀ = 20.45 ± 0.25 µg/mL), in the range of 16.44 ± 0.26 to 30.50 ± 0.50 µg/mL. Furthermore, the molecular docking study was performed to determine the interaction modes of newly synthesized compounds at the active site of the target enzymes. ADMET properties were calculated to evaluate the drug-likeness of all compounds. Conclusions: In this study, a new series of quinazolinone derivative compounds with potentially active antiurease and antiacetylcholinesterase inhibitions were synthesized, consistent with in silico studies.