2-(4-Fluorophenyl)-quinazolin-4(3H)-one as a novel tyrosinase inhibitor: Synthesis, inhibitory activity, and mechanism
2-(4-Fluorophenyl)-quinazolin-4(3H)-one (FQ) was synthesized, and its structure was identified with 1H nuclear magnetic resonance (1H NMR), 13C nuclear magnetic resonance (13C NMR), fourier transform infrared spectroscopy (FTIR), and high resolution mass spectrometry (HRMS). From the enzyme analysis, the results showed that it could inhibit the diphenolase activity of tyrosinase (IC50 = 120 ± 2 μM). Furthermore, the results of kinetic studies showed that the compound was a reversible mixed-type inhibitor, and that the inhibition constants were determined to be 703.2 (KI) and 222.1 μM (KIS). The results of fluorescence quenching experiment showed that the compound could interact with tyrosinase and the substrates (tyrosine and l-DOPA). Molecular docking analysis revealed that the mass transfer rate was affected by FQ blocking the enzyme catalytic center. In brief, current study identified a novel tyrosinase inhibitor which deserved further study for hyperpigmentation drugs.