Дослідження комплексоутворення калікс[4]aрену та калікс[4]резорцинарену із смоляними кислотами методом ОФ ВЕРХ. Визначення констант зв’язування

• Date: 2016
• Main Authors: Kalchenko, O. I., Cherenok, S. O., Solovyov, A. V., Gorbatchuk, V. V., Suikov, S. Yu., Kalchenko, V. I.
• Format: Article
• Language: English
• Published: National University of Pharmacy 2016
• Subjects: калікс[4]арени; смоляні кислоти; обернено-фазна високоефективна рідинна хроматографія; комплекси включення; константи зв’язування; молекулярне моделювання; УДК 547.03 547.562
• Online Access: https://ophcj.nuph.edu.ua/article/view/ophcj.16.884
• Journal Title: Journal of Organic and Pharmaceutical Chemistry

The Host-Guest complexation of octakis-(diphenoxyphosphoryloxy)tetramethylcalix[4]resorcinarene (CR) and 5,17-bis-(N-tolyliminomethyl)-25,27-dipropoxycalix[4]arene (CA) with 6 diterpenoid (resin) acids has been studied by the reversed phase high-performance liquid chromatography (RP HPLC). The chromatographic characteristics (retention time tR and retention factor k’) of resin acids have been determined. The lipophilicity values log P of the acids, binding constants KA (395-682 M-1 for CR and 844-1268 M-1 for CA), as well as Gibbs free energies ∆G (-14.79 – -16.14 kJ/mol for CR and -16.70 – -17.67 kJ/mol for CA) of the complexes with resin acids have been calculated. Molecular modelling of CA complexes has revealed the presence of hydrogen bonds between carboxylic groups of acids and nitrogen atoms of imino groups at the upper rim or oxygen atoms of the hydroxyl groups at the lower rim of the CA macrocycle. Molecular modelling of CR complexes has shown the presence of hydrogen bonds between carboxylic groups of acids and oxygen atoms of diphenoxyphosphoryloxy groups at the upper rim of the CR macrocycle. The effect of log P values on KA values of the CR/CA complexes has been assessed. The linear dependence of the binding constants on the acid lipophilicity indicates a significant role of solvophobic interactions on the complexation. The relationship between supramolecular (KA) and physicochemical (log P, pKa) characteristics of acids has been determined.