Different characteristics of cleavage kinetics of resin-bound amino alcohols and their peptide derivatives were observed in acid containing protic and aprotic solvent mixtures. The hydrolysis reactions are hindered by steric crowding around the cleaving C--O bond and accelerated by the special solvation effect of CF(3)CH(2)OH on the peptide chain as well as the increase of the strength and concentration of the acid. In trifluoroacetic acid containing mixtures, trifluoroacetylation of the peptide alcohols was detected. The appearance of O-trifluoroacetyl serine and threonine derivatives is detected in cleavage mixtures containing trifluoroacetic acid in anhydrous solvent.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1002/psc.745 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Computational Insights into Hydrogen Atom Transfer Mediators in C-H Activation Catalysis of Nonheme Fe(IV)O Complexes.
J Phys Chem B
December 2024
Department of Chemistry and Biochemistry, Thapar Institute of Engineering and Technology, Patiala 147001, Punjab, India.
This study presents a detailed density functional theory (DFT) investigation into the mechanism and energetics of C-H activations catalyzed by bioinspired Fe(IV)O complexes, particularly in the presence of -hydroxy mediators. The findings show that these mediators significantly enhance the reactivity of the iron-oxo complex. The study examines three substrates with varying bond dissociation energies─ethylbenzene, cyclohexane, and cyclohexadiene─alongside the [Fe(IV)O(N4Py)] complex.
View Article and Find Full Text PDFReplication Kinetics, Pathogenicity and Virus-induced Cellular Responses of Cattle-origin Influenza A(H5N1) isolates from Texas, United States.
Emerg Microbes Infect
December 2024
Host-pathogen interactions (HPI) and Disease Intervention and Prevention (DIP) programs, Texas Biomedical Research Institute, San Antonio, TX 78227, USA.
The host range of HPAIV H5N1 was recently expanded to include ruminants, particularly dairy cattle in the United States (US). Shortly after, human H5N1 infection was reported in a dairy worker in Texas following exposure to infected cattle. Herein, we rescued the cattle-origin influenza A/bovine/Texas/24-029328-02/2024(H5N1, rHPbTX) and A/Texas/37/2024(H5N1, rHPhTX) viruses, identified in dairy cattle and human, respectively, and their low pathogenic forms, rLPbTX and rLPhTX, with monobasic HA cleavage sites.
View Article and Find Full Text PDFDehydrogenative Coupling of Alcohols with Hydrazines under Nickel Catalysis.
J Org Chem
December 2024
Department of Chemistry, Indian Institute of Science Education and Research (IISER) Tirupati, Tirupati 517619, India.
The development of efficient and robust catalytic systems based on earth-abundant transition metals for fundamentally new transformations is crucial for sustainable chemical synthesis. Herein, an effective and selective Ni-catalyzed dehydrogenative coupling of alcohols with hydrazines with the liberation of ammonia gas is reported. Although several methods were documented for the -alkylation reaction, the present strategy is conceptually novel, and the reaction proceeds through a pathway involving N-N bond cleavage of phenylhydrazine followed by hydrogen autotransfer.
View Article and Find Full Text PDFHalf-Life Extension of the IgG-Degrading Enzyme (IdeS) Using Fc-Fusion Technology.
Eur J Immunol
December 2024
Institut National de la Santé et de la Recherche Médicale, Centre de Recherche des Cordeliers, CNRS, Sorbonne Université, Université Paris Cité, Paris, France.
Imlifidase (IdeS) is a bacterial protease that hydrolyzes human IgG in their hinge region, decreasing their half-life and abrogating their Fc-mediated properties. It is now successfully used in therapy to prevent graft rejection during kidney transplants and is being clinically evaluated in several IgG-mediated autoimmune diseases. IdeS short half-life however limits its clinical use, particularly in the case of chronic diseases that would request repeated administrations.
View Article and Find Full Text PDFStructures, mechanisms, and kinetic advantages of the SgrAI filament forming mechanism.
Crit Rev Biochem Mol Biol
December 2024
The Salk Institute for Biological Studies, La Jolla, California, USA.
This review documents investigations leading to the unprecedented discovery of filamentation as a mode of enzyme regulation in the type II restriction endonuclease SgrAI. Filamentation is defined here as linear or helical polymerization of a single enzyme as occurs for SgrAI, and has now been shown to occur in many other enzyme systems, including conserved metabolic enzymes. In the case of SgrAI, filamentation activates the DNA cleavage rate by up to 1000-fold and also alters the enzyme's DNA sequence specificity.
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!