A detailed analysis of proton-proton-transfer dynamics under magic angle spinning NMR is presented. Results obtained on model compounds are evaluated under different experimental conditions and NMR mixing schemes. It is shown that the resulting buildup rates can be interpreted in terms of internuclear proton-proton distances provided that an appropriate theoretical description is chosen. As demonstrated in two test applications, these dependencies can be used in the context of a three-dimensional structure determination in the solid state.

A molecule with an anisotropic magnetic susceptibility is spontaneously aligned in a static magnetic field. Alignment of such a molecule yields residual dipolar couplings and pseudocontact shifts. Lanthanide ions have recently been successfully used to provide an anisotropic magnetic susceptibility in target molecules either by replacing a calcium ion with a lanthanide ion in calcium-binding proteins or by attaching an EDTA derivative to a cysteine residue via a disulfide bond. Here we describe a novel enantiomerically pure EDTA derived tag that aligns stronger due to its shorter linker and does not suffer from stereochemical diversity upon lanthanide complexation. We observed residual (15)N,(1)H-dipolar couplings of up to 8 Hz at 800 MHz induced by a single alignment tensor from this tag.

In this paper we show that water insoluble compounds dissolved in poly-gamma-benzyl-glutamate are amenable to the measurement of a number of homo- and heteronuclear dipolar couplings. The sensitivity and experimental precision of dipolar couplings are sufficient to obtain a good match with the structure. In order to achieve the necessary precision for H,C dipolar couplings between protons and carbons that are not directly bound a new method for the measurement of heteronuclear long range couplings is introduced that allows a one-parameter fit to a HSQC-based experiment as reference experiment. The methodology is applied to menthol (1R, 3S, 4R).

A combination of NMR spectroscopy and mass spectrometry has been crucial in determining the structure of the relatively stable light‐inactivated form of the cofactor of the hydrogenase Hmd (see scheme). These studies have shown that the chromophore bound to GMP through a phosphoester linkage is a pyridone derivative.