Synthesis of a novel p-hydroxycinnamic amide and its interaction with bovine serum albumin

Abstract

A novel p-hydroxycinnamic amides ((E)-4-(3-((4-(N-(5-methoxy-pyrimidin-2-yl) sulfamoyl) phenyl)amino)-3-oxoprop-1-en-1-yl)phenyl acetate (MSAP) was synthesized and confirmed by 1H NMR, 13CNMR ESI-MS, elemental analysis and single-crystal X-ray diffraction analysis. The crystal structure of the complex is monoclinic system and space group is P21/c. The interactions between MSAP and bovine serum albumin (BSA) was investigated with fluorescence and UV–Vis spectral analysis and molecular simulation. According to the fluorescence quenching calculation, the corresponding thermodynamic parameters (ΔH, ΔG and ΔS etc.), bimolecular quenching rate constant (kq), apparent quenching constants (Ksv) and binding sites number (n) were calculated. The distances (r) between BSA and its derivatives were obtained according to Foster’s non-radioactive energy transfer theory. Conformational changes in BSA were observed from synchronous fluorescence spectra. Furthermore, the site marker competitive experiments indicated that the binding of compounds to BSA primarily took place in site I (sub-domain IIA).