The Study of the Complexation of Calix[4]arene-Hydroxymethylphosphonic Acid and Calix[4]arene-Hydroxymethyldimethylphosphine Oxide with Antiviral Drugs

The host-guest complexation of cone-shaped calix[4]arene-hydroxymethylphosphonic acid (CPA) and calix[4]arene-hydroxymethyldimethylphosphine oxide (CPO) with active pharmaceutical ingredients of antiviral drugs Remdesivir, Nevirapine, Vesatolimod, and Bictegravir in the aqueous-organic mobile phase on a Zorbax CN column has been studied using RP HPLC method. By analyzing the dependence of the drug capacity values on the concentration of calixarene in the mobile phase, the stability constants (КА = 3672 - 6884 M-1) of the complexes formed have been determined. Quantum-chemical calculations show that the drugs studied form supramolecular exo-complexes with CPA and CPO molecules. These complexes are stabilized by intermolecular hydrogen bonds of proton donor groups P(O)(OH)2 CPA and proton acceptor groups Me2P=O CPO with the amino group of Remdesivir, the amide group of Nevirapine, the amino group and amide group of Vesatolimod, and the amide group of Bictegravir.