Effect of organic ligands with conjugated π‐bonds on the structure of iodine–α‐dextrin complexes

Abstract

Using X-ray data for iodine-α-dextrin complexes and the results of quantum chemical ab initio restricted Hartree-Fock/3-21G(**) level calculations, a model of drug active complex (AC) Armenicum with anti-HIV action was proposed. It was suggested that the drug AC contains molecular iodine allocated inside of α-dextrin helix and coordinated by lithium halogenides and a protein component of lymphocyte ribosomes. The electronic structure of I(2) in this complex differs from its characteristics in complexes with organic ligands or the free I(2) . In the considered ACs, the molecular iodine displays acceptor (donor) properties toward the α-dextrins (lithium halogenides). A mechanism of Armenicum anti-HIV action is suggested. Under the influence of molecular iodine-containing drug AC, the structure of HIV DNA is modified-it becomes more π-donor-active against proteins and peptide nucleotides of viral DNA form a stable complex with molecular iodine and lithium halogenides.