Synthesis of Tailed Metalloporphyrins Modified with 2‐Chloronicotinic Acid and Interactions with Human Serum Albumin

Abstract

Two kinds of free‐base tailed porphyrins modified with 2‐chloronicotinic acid and the corresponding Zn porphyrins have been synthesized. They have been characterized by elemental analysis and NMR, UV/Vis, fluorescence spectra, and infrared spectroscopies. Their configurations have been optimized through theoretical calculations. The fluorescence quantum yields were determined by a comparative method. The interactions between the Zn porphyrins and human serum albumin have been studied by means of fluorescence spectra. The experimental results showed that the interaction mechanism involved a combined fluorescence quenching process (static and dynamic quenching) and that the main driving force was hydrophobic in nature. Quenching constants, binding constants, thermodynamic parameters, and binding distances have been determined.

Differences between the binding modes of enantiomers S/R-nicotine to acetylcholinesterase

“…In addition, the negative Gibbs free energy change (DG) reected the spontaneity of the interaction process. [39][40][41] The interaction forces were further analyzed using the simulation trajectory of different stages in the MD simulation process. As shown in the upper panel of Fig.…”

Exploring the binding pattern between pepsin and deferasirox using detailed experimental and computer simulation methods

“…DG < 0 indicated that the binding between pepsin and DFX molecules was spontaneous; DH < 0, DS < 0 indicated that the main force of pepsin and DFX molecule binding was the hydrogen bond. 28 3.2 The effects of interaction on the structure of pepsin 3.2.1 Synchronous uorescence spectroscopy. Synchronous uorescence can distinguish the overlapping peaks of endogenous uorescent chromospheres in the ordinary uorescence spectrum, so that the uorescence change of a single uorescent chromophore aer the addition of the quencher can be observed.…”

“…Δ G < 0 indicated that the binding between pepsin and DFX molecules was spontaneous; Δ H < 0, Δ S < 0 indicated that the main force of pepsin and DFX molecule binding was the hydrogen bond. 28 …”