Qualitative aspects of hydrogen-deuterium exchange in the proton, carbon-13, and nitrogen-15 nuclear magnetic resonance spectra of viomycin in aqueous solution

Abstract

The 1H, 13C and 15N high field NMR spectra of the cyclic peptide viomycin were fully assigned using homo- and heteronuclear double resonance experiments and pH effects. It is shown how the 2- and 3-bond H.sbd.D isotope effects upn carbonyl resonances may assist in their assignment. The resistance to exchange with solvent water of the amide proton involved in the transannular H bond is oberved directly in the 1H spectra, via the isotope effect on a carbonyl resonance in the 13C spectra, and via the 1-bond 1H coupling in the 15N spectra.