Flavones are polyphenolic compounds endowed with diverse pharmacological and biological activities with which have many derivatives with different structures.In this work, UV−vis spectroscopy, fluorescence spectroscopy and molecular docking have been used to investigate the structure-activity relationship of the interaction between different flavones and DNA in vitro. From it we could know the studied flavones are all intercalate into the double helix of DNA, suggest that the same skeleton structure in flavones may the main reason for the interaction mode. At the same time, we could find that different flavones lead to different results in the interaction which results from different structure between them, such as the number of hydroxyl groups, the location of hydroxyl groups, and steric hindrance et al. These findings are important in the research about structure-activity relationships, which may meaningful for drug discovery, drug design, novel medicines design and help us understand the structure-activity relationship between flavones at the molecular level.

No abstract

In this study, fluorescence spectroscopy and molecular modeling approaches were employed to investigate the binding of methotrexate to human serum albumin (HSA) under physiological conditions. From the mechanism, it was demonstrated that fluorescence quenching of HSA by methotrexate results from the formation of a methotrexate/HSA complex. Binding parameters calculated using the Stern-Volmer method and the Scatchard method showed that methotrexate binds to HSA with binding affinities in the order 10 L·mol . Thermodynamic parameter studies revealed that the binding reaction is spontaneous, and that hydrogen bonds and van der Waals interactions play a major role in the reaction. Site marker competitive displacement experiments and a molecular modeling approach demonstrated that methotrexate binds with appropriate affinity to site I (subdomain IIA) of HSA. Furthermore, we discuss some factors that influence methotrexate binding to HSA.