Solid-State 15N and 17O NMR Studies of S-Nitrosothiols.

Abstract

We report a solid-state 15N and 17O NMR study of two representative S-nitrosothiols (RSNO): S-nitroso N-acetylpenicillamine (SNAP) and S-nitrosoglutathione (GSNO). The 15N and 17O NMR tensors are experimentally determined for the first time for this important class of nitric-oxide (NO)-related compounds. The observed NMR characteristics for RSNO include large 15N and 17O chemical shift anisotropies and large 17O quadrupole coupling constants. Quantum chemical calculations are also performed for the 15N and 17O NMR tensors in two simple RSNO models: t-BuSNO and MeSNO. On the basis of computational results, we have identified the molecular orbitals that are responsible for the observed large chemical shift anisotropies in RSNO compounds.