Chitosan 2-thiourea derivatives with various substituents, including 3-(methylthio)propyl, phenyl, octyl and ethoxycarbonyl, at the 2-position of the glucosamine skeleton were prepared via isothiocyanates with the above substituents. The obtained chitosan 2-thiourea derivatives without ethoxycarbonyl were then esterified to develop a new series of chitosan 2-thiourea-3,6-diphenylcarbamate derivatives. The enantioseparation properties of the obtained chitosan derivatives were examined by high-performance liquid chromatography (HPLC). These results demonstrated that these chitosan 2-[3-(methylthio)propylthiourea]-3,6-diphenylcarbamate derivatives showed attractive chiral recognition abilities, especially for dihydropyridine calcium antagonist racemates. This result was probably attributed to the fact that the 2-thiourea substituents of this series of chitosan derivatives, as well as the 3,6-phenylcarbamate substituents, provided more favorable sites, which evidently enhanced the interactions between the enantiomers and the chitosan derivatives. The mechanism involved in the enantioseparation of the chitosan 2-[3-(methylthio)propylthiourea]-3,6-diphenylcarbamate derivatives was further discussed by molecular docking simulation.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.carbpol.2022.119888 | DOI Listing |
Curr Gene Ther
January 2025
Department of Chemistry and Environmental Sciences, IBILCE, São Paulo State University - UNESP, São José do Rio Preto, São Paulo, Brazil.
Introduction: The clinical translation of chitosan-based formulations for siRNA delivery has been partially limited by their poor stability/solubility at physiological conditions, although they have good biocompatibility and cost-effectiveness.
Method: In this study, the chitosan was O-substituted with diisopropylethylamine (DIPEA) groups, which improved its solubility at pH 7.4 by increasing the degree of ionization and enhanced the ability of chitosan to load siRNA at very low amine/phosphate (N/P) ratios.
J Exp Clin Cancer Res
January 2025
Department of Urology, Ren Ji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
Background: Most patients with prostate cancer inevitably progress to castration-resistant prostate cancer (CRPC), at which stage chemotherapeutics like docetaxel become the first-line treatment. However, chemotherapy resistance typically develops after an initial period of therapeutic efficacy. Increasing evidence indicates that cancer stem cells confer chemotherapy resistance via exosomes.
View Article and Find Full Text PDFInt J Biol Macromol
January 2025
Key Laboratory of Bio-based Material Science & Technology (Ministry of Education), Northeast Forestry University, Harbin 150040, China; College of Material Science and Engineering, Northeast Forestry University, Harbin 150040, China.
Carboxymethyl chitosan (CMCh) is a natural polysaccharide derivative with biodegradability, rich in active amino and carboxyl groups. It can act as a ligand to coordinate with rare earth ions, transferring absorbed energy to the central ion to sensitize its luminescence. In this paper, CMCh-Tb was prepared as a solid fluorescent probe by mixing CMCh solution with Tb.
View Article and Find Full Text PDFRSC Adv
January 2025
Department of Chemical Engineering, Polytechnique Montreal Montreal QC Canada
Chitosan, a biodegradable and biocompatible natural polymer composed of β-(1-4)-linked -acetyl glucosamine (GlcNAc) and d-glucosamine (GlcN) and derived from crustacean shells, has been widely studied for various biomedical applications, including drug delivery, cartilage repair, wound healing, and tissue engineering, because of its unique physicochemical properties. One of the most promising areas of research is the investigation of the immunomodulatory properties of chitosan, since the biopolymer has been shown to modulate the maturation, activation, cytokine production, and polarization of dendritic cells and macrophages, two key immune cells involved in the initiation and regulation of innate and adaptive immune responses, leading to enhanced immune responses. Several signaling pathways, including the cGAS-STING, STAT-1, and NLRP3 inflammasomes, are involved in chitosan-induced immunomodulation.
View Article and Find Full Text PDFAdv Healthc Mater
January 2025
College of Chinese Medicinal Materials, Jilin Agricultural University, Changchun, 130118, China.
Natural plant-derived polysaccharides exhibit substantial potential for treating ulcerative colitis (UC) owing to their anti-inflammatory and antioxidant properties and favorable safety profiles. However, their practical application faces several challenges, including structural instability in gastric acid, imprecise targeting of inflamed regions, and limited intestinal retention times. To address these limitations, pH-responsive, colon-targeting microspheres (pWGPAC MSs) are developed for delivering phosphorylated wild ginseng polysaccharides (pWGP) to alleviate UC.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!