Selective excitation enables encoding and measurement of multiple diffusion parameters in a single experiment.

Band selectivity to address specific resonances in a spectrum enables one to encode individual settings for diffusion experiments. In a single experiment, this could include different gradient strengths (enabling coverage of a larger range of diffusion constants), different diffusion delays, or different gradient directions (enabling anisotropic diffusion measurement). In this report, a selective variant of the bipolar pulsed gradient eddy current delay (BPP-LED) experiment, enabling selective encoding of three resonances, was implemented.

Macrocyclic Tetramers-Structural Investigation of Peptide-Peptoid Hybrids.

Outstanding affinity and specificity are the main characteristics of peptides, rendering them interesting compounds for basic and medicinal research. However, their biological applicability is limited due to fast proteolytic degradation. The use of mimetic peptoids overcomes this disadvantage, though they lack stereochemical information at the -carbon.

Configuration determination by residual dipolar couplings: accessing the full conformational space by molecular dynamics with tensorial constraints.

Residual dipolar couplings (RDCs) and other residual anisotropic NMR parameters provide valuable structural information of high quality and quantity, bringing detailed structural models of flexible molecules in solution in reach. The corresponding data interpretation so far is directly or indirectly based on the concept of a molecular alignment tensor, which, however, is ill-defined for flexible molecules. The concept is typically applied to a single or a small set of lowest energy structures, ignoring the effect of vibrational averaging.

16-Electron pentadienyl- and cyclopentadienyl-ruthenium half-sandwich complexes with bis(imidazol-2-imine) ligands and their use in catalytic transfer hydrogenation.

Bis(η(5)-2,4-dimethylpentadienyl)ruthenium(II), [(η(5)-C7H11)2Ru] (1, “open ruthenocene”), which has become accessible in high yield and large quantities via an isoprene-derived diallyl ruthenium(IV) complex, can be converted into the protonated open ruthenocene 2 by treatment with HBF4 and subsequently into the protonated half-open ruthenocene 3 by reaction with cyclopentadiene. The electronic structure of 3 was studied by DFT methods, revealing that the CH-agostic complex [(η(5)-C5H5)Ru{(1-4η)-C7H12-η(2)-C(5),H(5)}]BF4 (A) represents the global minimum, which is 3.7 kcal mol(−1) lower in energy than the hydride complex [(η(5)-C5H5)RuH(η(5)-C7H11)]BF4 (B).