A thermally induced irreversible conformational transition of amylose tris(3,5-dimethylphenylcarbamate) (i.e., Chiralpak AD) chiral stationary phase (CSP) in the enantioseparation of dihydropyrimidinone (DHP) acid racemate was studied for the first time by quasi-equilibrated liquid chromatography with cyclic van't Hoff and step temperature programs and solid-state ((13)C CPMAS and (19)F MAS) NMR using ethanol and trifluoroacetic acid (TFA)-modified n-hexane as the mobile phase. The conformational transition was controlled by a single kinetically driven process, as evidenced by the chromatographic studies. Solid-state NMR was used to study the effect of the temperature on the conformational change of the solvated phase (with or without the DHP acid enantiomers and TFA) and provided some viable structural information about the CSP and the enantiomers.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1021/ac034714e | DOI Listing |
BMC Vet Res
December 2024
Department of Research, Research and Development Station for Bovine, Arad, Romania.
Background: There are no studies belong NOTCH2 gene polymorphism in relation to reproductive and productive traits in Holstein cattle. The objective of the present study was to investigate the effect of NOTCH2 gene polymorphisms on productive and reproductive performance of fertile and anestrum cattle.
Methods: The cattle were classified into anestrus for 3-12 months postpartum (n = 115, 37.
J Xenobiot
December 2024
Department of Chemical Engineering, University of Pretoria, Pretoria 0028, South Africa.
The direct discharge of cationic surfactants into environmental matrices has exponentially increased due to their wide application in many products. These compounds and their degraded products disrupt microbial dynamics, hinder plant survival, and affect human health. Therefore, there is an urgent need to develop electroanalytical assessment techniques for their identification, determination, and monitoring.
View Article and Find Full Text PDFMar Drugs
December 2024
Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 119997 Moscow, Russia.
TRPA1 is a homotetrameric non-selective calcium-permeable channel. It contributes to chemical and temperature sensitivity, acute pain sensation, and development of inflammation. HCIQ2c1 is a peptide from the sea anemone that inhibits serine proteases.
View Article and Find Full Text PDFGels
December 2024
Horváth Csaba Memorial Laboratory of Bioseparation Sciences, Research Center for Molecular Medicine, Faculty of Medicine, Doctoral School of Medicine, University of Debrecen, 4032 Debrecen, Hungary.
Hydrogels like agarose have long been used as sieving media for the electrophoresis-based analysis of biopolymers. During gelation, the individual agarose strands tend to form hydrogen-bond mediated double-helical structures, allowing thermal reversibility and adjustable pore sizes for molecular sieving applications. The addition of tetrahydroxyborate to the agarose matrix results in transitional chemical cross-linking, offering an additional pore size adjusting option.
View Article and Find Full Text PDFJ Biol Chem
December 2024
Department of Molecular Cell and Developmental Biology, University of California, Santa Cruz, California, USA; Center for Molecular Biology of RNA, University of California, Santa Cruz, California, USA. Electronic address:
The spliceosome protein, SF3B1 associates with U2 snRNP during early spliceosome assembly for pre-mRNA splicing. Frequent somatic mutations in SF3B1 observed in cancer necessitates characterization of its role in identifying the branchpoint adenosine of introns. Remarkably, SF3B1 is the target of three distinct natural product drugs, each identified by their potent anti-tumor properties.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!