[reaction: see text] Thiol-disulfide exchange can be used to prepare multivalent conjugates of a small molecule or octapeptide displayed on dendrimers based on melamine. Exchange of four or eight thiopyridyl groups by captopril occurs at room temperature in methanol almost quantitatively. Exchange using the peptide requires higher temperatures and guanidinium chloride in DMF. While exchange on the tetravalent scaffold with four peptides is almost quantitative, sterics retard formation of the octavalent conjugate: the hexavalent conjugate forms readily.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1021/ol034161u | DOI Listing |
Chemistry
January 2025
University of Padova: Universita degli Studi di Padova, Dipartimento di Scienze Chimiche, Via Marzolo 1, 35131, Padova, ITALY.
Chalcogenide exchange reactions are an important class of bimolecular nucleophilic substitution reactions (SN2) involving sulfur and selenium species as nucleophile, central atom, and/or leaving group, which are fundamental throughout redox biology and metabolism. While thiol-disulfide exchange reactions have been deeply investigated, those involving selenium are less understood, especially with regards to the polarised selenenyl sulfides RSe-SR' even though the directed reactivity of selenenyl sulfides is biologically crucial for selenoenzymes such as thioredoxin reductase (TrxR) and glutathione peroxidase (GPx). Synthetic methods to create asymmetric selenenyl sulfides with high regiochemical purity only emerged over the last five years; this functional group has already demonstrated powerful applications to cell biology, through probes for molecular imaging (e.
View Article and Find Full Text PDFAdv Healthc Mater
January 2025
Key Laboratory of Colloid and Interface Chemistry of the Ministry of Education, School of Chemistry and Chemical Engineering, Shandong University, Jinan, Shandong, 250100, China.
Coacervates have garnered significant attention as potential drug carriers. However, the instability resulting from their intrinsic membrane-free nature restricts the application of coacervates in drug delivery. Herein, the engineering of poly(ethylene glycol) nanoparticles (PEG NPs) is reported using coacervates composed of PEG and polyphenols as the templates, where PEG is subsequently cross-linked based on different chemistries (e.
View Article and Find Full Text PDFDrug Dev Res
February 2025
School of Pharmacy, Changzhou University, Changzhou, PR China.
Poor selectivity to tumor cells is a major drawback in the clinical application of the antitumor drug docetaxel (DTX). Peptide-drug conjugates (PDCs) constructed by modifying antitumor drugs with peptide ligands that have high affinity to certain overexpressed receptors in tumor cells are increasingly assessed for their possibility of tumor-selective drug delivery. In the present research, DTX is condensed with 3-(pyridin-2-yldisulfanyl) propanoic acid via ester bond to obtain the intermediate Py-SS-DTX.
View Article and Find Full Text PDFInorg Chem
December 2024
Center for AIE Research, College of Materials Science and Engineering, Shenzhen University, Shenzhen 518060, China.
The ability of photosensitizers (PSs) to generate reactive oxygen species (ROS) is crucial for photodynamic therapy (PDT). However, many traditional PSs face the drawbacks that aggregation-caused quenching (ACQ) and highly expressed glutathione (GSH) in the tumor microenvironment seriously limit their ROS generation ability. Herein, we report two cationic dinuclear iridium complexes, and , which possess aggregation-induced emission (AIE).
View Article and Find Full Text PDFMAbs
October 2024
Department of Analytical Chemistry, Regeneron Pharmaceuticals, Inc, Tarrytown, NY, USA.
Non-reduced peptide mapping provides essential data for characterizing therapeutic monoclonal antibodies by isolating disulfide connections between specific cysteines. However, conventional digestive strategies used throughout the biopharmaceutical industry have been shown to cause unintentional rearrangement of disulfide connections (disulfide scrambling), thus generating connectivity profiles that do not accurately represent the protein being analyzed. Common misconceptions (e.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!