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A general protocol is developed to obtain D-glucosamine from three widely available biomass residues: shrimp shells, cicada sloughs, and cockroaches. The protocol includes three steps: (1) demineralization, (2) deproteinization, and (3) chitin hydrolysis. This simple, general protocol opens the door to obtain an invaluable nitrogen-containing compound from three biomass residues, and it can potentially be applied to other chitin sources. White needle-like crystals of pure D-glucosamine are obtained in all cases upon purification by crystallization. Characterization data (NMR, IR, and mass spectrometry) of D-glucosamine obtained from the three chitin sources are similar and confirm its high purity. NMR investigation demonstrates that D-glucosamine is obtained mainly as the α-anomer, which undergoes mutarotation in aqueous solution achieving equilibrium after 440 min, in which the anomeric glucosamine distribution is 60% α-anomer and 40% β-anomer.
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http://dx.doi.org/10.1002/gch2.201800046 | DOI Listing |
Haematologica
September 2025
Department of Oncology, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, MD,.
Immunotherapies, including cell therapies, are effective anti-cancer agents. However, cellular product persistence can be limiting with short functional duration of activity contributing to disease relapse. A variety of manufacturing protocols are used to generate therapeutic engineered T-cells; these differ in techniques used for T-cell isolation, activation, genetic modification, and other methodology.
View Article and Find Full Text PDFStroke
September 2025
Department of Neurology, Yale School of Medicine, New Haven, CT (L.H.S.).
Preclinical stroke research faces a critical translational gap, with animal studies failing to reliably predict clinical efficacy. To address this, the field is moving toward rigorous, multicenter preclinical randomized controlled trials (mpRCTs) that mimic phase 3 clinical trials in several key components. This collective statement, derived from experts involved in mpRCTs, outlines considerations for designing and executing such trials.
View Article and Find Full Text PDFHigh Alt Med Biol
September 2025
International Commission for Mountain Emergency Medicine (ICAR MEDCOM), Zurich, Switzerland.
McLaughlin, Kyle, Charley Shimanski, Ken Zafren, Ian Jackson, Gerold Biner, Maurizio Folini, Andreas Hermansky, Eric Ridington, Peter Hicks, Giacomo Strapazzon, Marika Falla, Alastair Hopper, Dave Weber, Ryan Jackson, and Hermann Brugger. Helicopter rescue at very high altitude: Recommendations of the International Commission for Mountain Emergency Medicine (ICAR MedCom) 2025. 00:00-00, 2025.
View Article and Find Full Text PDFOrg Lett
September 2025
Institute of Advanced Synthesis, School of Chemistry and Molecular Engineering, Nanjing Tech University, Nanjing 211816, China.
Presented herein is a protocol for the iron-catalyzed [4 + 1] cycloadditions of -Boc-imines with β-ketosulfoxonum ylides through a succession of nucleophilic additions and intramolecular annulation, giving access to functionalized oxazolidine-2-ones in generally good yields. In contrast to the renown Corey-Chaykovsky reaction via N attack to furnish aziridines, this method afforded oxazolidine-2-ones via an O-nucleophilic attack. Features of this strategy include readily accessible starting materials, sustainable catalyst, post-functionalizations of complex molecules, scalability, and exceptional control over diastereoselectivity.
View Article and Find Full Text PDFJ Chem Theory Comput
September 2025
Institute of Organic Chemistry, TU Braunschweig, Hagenring 30, 38106 Braunschweig, Germany.
An automated protocol enabling the efficient computation of unique potential coupling constants is presented. Several modern density functional (DFT) methods are tested against coupled cluster theory (CCSD(T)) in order to evaluate their quality in producing reliable compliance matrix off-diagonal elements. While force coupling constants could serve as descriptors of electron delocalization in general, we tested the ability of coupling compliance constants as descriptors of the Dewar-Chatt-Duncanson model in VCO, CrCO, MnCO, FeCO, NiCO, CuCO, FeCO and the isoelectronic hexacarbonyls of the 3d and 5d series from Ti to Co, and Hf to Ir, respectively.
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