The first example of magic angle spinning NMR on crowns has been demonstrated. The ability to monitor a reaction on a crown and to confirm the structure of the reaction product directly on the crown without resorting to chemical cleavage should greatly enhance the utility of this convenient format for combinatorial chemistry.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1021/jo961590f | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Observation of H-H J-couplings in fast magic-angle-spinning solid-state NMR spectroscopy.
Nat Commun
December 2024
Institut des Sciences et Ingénierie Chimiques, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015, Lausanne, Switzerland.
While H-H J-couplings are the cornerstone of all spectral assignment methods in solution-state NMR, they are yet to be observed in solids. Here we observe H-H J-couplings in plastic crystals of (1S)-(-)-camphor in solid-state NMR at magic angle spinning (MAS) rates of 100 kHz and above. This is enabled in this special case because the intrinsic coherence lifetimes at fast MAS rates become longer than the inverse of the H-H J couplings.
View Article and Find Full Text PDFIntegrative determination of atomic structure of mutant huntingtin exon 1 fibrils implicated in Huntington disease.
Nat Commun
December 2024
Department of Theory and Bio-Systems, Max Planck Institute of Colloids and Interfaces, 14476, Potsdam, Germany.
Neurodegeneration in Huntington's disease (HD) is accompanied by the aggregation of fragments of the mutant huntingtin protein, a biomarker of disease progression. A particular pathogenic role has been attributed to the aggregation-prone huntingtin exon 1 (HTTex1), generated by aberrant splicing or proteolysis, and containing the expanded polyglutamine (polyQ) segment. Unlike amyloid fibrils from Parkinson's and Alzheimer's diseases, the atomic-level structure of HTTex1 fibrils has remained unknown, limiting diagnostic and treatment efforts.
View Article and Find Full Text PDFIonic Crosslinking of Linear Polyethyleneimine Hydrogels with Tripolyphosphate.
Gels
December 2024
Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Departamento de Ciencias Químicas, Ciudad Autónoma de Buenos Aires 1113, Argentina.
In this work, the mechanical properties of hydrogels based on linear polyethyleneimine (PEI) chemically crosslinked with ethyleneglycoldiglycidyl ether (EGDE) were improved by the ionic crosslinking with sodium tripolyphosphate (TPP). To this end, the quaternization of the nitrogen atoms present in the PEI structure was conducted to render a network with a permanent positive charge to interact with the negative charges of TPP. The co-crosslinking process was studied by H high-resolution magic angle spinning (H HRMAS) NMR and X-ray photoelectron spectroscopy (XPS) in combination with organic elemental analysis and inductively coupled plasma mass spectrometry (ICP-MS).
View Article and Find Full Text PDFTriphenyl-Modified Mixed-Mode Stationary Phases With and Without Embedded Ion-Exchange Sites for High-Performance Liquid Chromatography.
J Sep Sci
December 2024
Institute of Pharmaceutical Sciences, Pharmaceutical (Bio-)Analysis, University of Tübingen, Tübingen, Germany.
The present work reports on the preparation, characterization, and evaluation of a set of novel triphenyl-modified silica-based stationary phases without and with embedded ion-exchange sites for mixed-mode liquid chromatography. The three synthesized triphenyl phases differed in additionally incorporated ion-exchange sites. In one embodiment, allyltriphenylsilane was bonded to thiol-modified silica by thiol-ene click reaction, leading to particles with no ion-exchange sites.
View Article and Find Full Text PDFComparative lipidomic and metabolomic profiling of mdx and severe mdx-apolipoprotein e-null mice.
Skelet Muscle
December 2024
Department of Physiology and Aging, University of Florida, Gainesville, FL, USA.
Despite its notoriously mild phenotype, the dystrophin-deficient mdx mouse is the most common model of Duchenne muscular dystrophy (DMD). By mimicking a human DMD-associated metabolic comorbidity, hyperlipidemia, in mdx mice by inactivating the apolipoprotein E gene (mdx-ApoE) we previously reported severe myofiber damage exacerbation via histology with large fibro-fatty infiltrates and phenotype humanization with ambulation dysfunction when fed a cholesterol- and triglyceride-rich Western diet (mdx-ApoE). Herein, we performed comparative lipidomic and metabolomic analyses of muscle, liver and serum samples from mdx and mdx-ApoE mice using solution and high-resolution-magic angle spinning (HR-MAS) H-NMR spectroscopy.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!