Complex Formation Between the Antiviral Nucleoside Ribavirin (1-·B-D-Ribofuranosyl-1,2,4-Triazole-3-Carboxamide) and Bivalent Metal Ions: 1H and 13C NMR Studies, and Comparison with Inosine

Abstract

The interactions O\u27f metal chlorides (MeClz) of group !La (Me = Mg, Ca, Sr, Ba) and group !lb (Me = Zn, Cd, Hg) with ribavi.rin, a potent broad spectrum antiviral nucleoside, and with .Us structural analogue inosine were studied in DMSO-ds using 1H and 130 NMR methods. Proton limiting shift analysis was made and 1H and 130 spin lattice relaxation times oif ribavirin as a function o:f metal ion concentrations were determined. The nature of the interactions was determined on the basis of these data. The composition 01f comple1xes was determined using J0<b-plo.ts as 1 : 1 and the formation constants o·f 1 : 1 Me2+ -ribavirin and Me2+-inosine complexoo in equilibrium were evaluated either by concentration dependence or by a variaible temperature method