LAUSR

Abstract The structural properties including quantum chemical parameters and theoretical spectrum of a newly synthesized compound, ethyl 5-phenyl-2-(o-tolyl)-2H-1,2,3- triazole-4-carboxylate (EPTC) have been investigated using GaussView5.0 program package and the time dependent density functional theory (TD DFT). Then EPTC has been studied on the interactions with three kinds of globular proteins including human serum albumin (HSA), human immunoglobulin (HIgG) and bovine hemoglobin (BHb) by using molecular docking and a series of spectroscopic methods under the simulative physiological conditions. The presence of EPTC led to the remarkable fluorescence enhancement for these proteins and hydrophobic forces played a major role in stabilizing EPTC-protein systems. Molecular docking was performed and the results showed that the EPTC moiety binds to the hydrophobic cavity of three proteins, which are in good agreement with the spectroscopic measurements. The results from UV–visible, three-dimensional (3D) and synchronous fluorescence measurements show that EPTC has influence on the conformational of proteins and the microenvironment surrounding HSA, HIgG or BHb in aqueous solution.