A novel quinazoline derivative, 3-[2-(3, 4-Dimethoxy phenyl)-ethyl]-2-methyl-3H quinazoline-4-one has been synthesized and characterized by FTIR, NMR, and single crystal X-ray diffraction technique. The molecular stability is mainly due to weak but collective contributions of significant intra and inter molecular C-H horizontal ellipsis O, C-H horizontal ellipsis N, C-O horizontal ellipsis pi, and pi-pi hydrogen bond interactions and those interactions quantified by Hirshfeld surface analysis. The molecular geometry has been optimized using the B3LYP/DFT method. The electrostatic potential map, nonlinear optical properties, NBO analysis, and potential energy scan are also described. Molecular docking study carried out between quinazoline derivative and antimicrobial receptor proteins.