The stereoselective preparation of the β-d-GlcNAc-(1→4)-D-Glc disaccharide starting from known 4-O-[6-O-(1-methoxy-1-methylethyl)-3,4-O-isopropylidene-β-d-talopyranosyl]-2,3:5,6-di-O-isopropylidene-aldehydo-D-glucose dimethyl acetal (2), in turn easily obtained from lactose, is reported. Key steps of this new procedure, that avoids the glycosylation reaction, are (a) a first epimerization at C-4' through an unusual procedure involving a completely stereospecific hydroboration-oxidation of the enol ether group of the hex-4-enopyranoside 4, obtained from 3 by base promoted acetone elimination, (b) an amination with inversion by S(N)2 reaction on an imidazylate intermediate, and, finally, (c) N-acetylation followed by complete deprotection.
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http://dx.doi.org/10.1016/j.carres.2014.01.020 | DOI Listing |
Anal Chim Acta
February 2025
Faculty of Chinese Medicine & State Key Laboratory of Quality Research in Chinese Medicine, Macau University of Science and Technology, Taipa, Macau, China. Electronic address:
Background: Carbohydrates exhibit diverse functions and extensive biological activities and are notable in the field of life sciences. However, their inherent diversity and complexity-steaming from variations in isomeric monomers, glycosidic bonds, configurations, etc.-present considerable challenges in structural analysis.
View Article and Find Full Text PDFJ Indian Soc Pedod Prev Dent
October 2024
Department of Pedodontics and Preventive Dentistry, Sardar Patel Post Graduate Institute of Dental and Medical Sciences, Lucknow, Uttar Pradesh, India.
Neurochem Res
January 2025
Wuxi School of Medicine, Jiangnan University, Wuxi, 214122, China.
Trehalose has neuroprotective effects in neurodegenerative diseases. This study aimed to explore the impact of trehalose on traumatic brain injury (TBI) by investigating its role in neuroprotection. The TBI mice model was established utilizing the cortical impact technique followed by trehalose treatment.
View Article and Find Full Text PDFNutrients
December 2024
Cryptobiotix, Technologiepark-Zwijnaarde 82, 9052 Gent, Belgium.
Background: The human gut microbiota develops in concordance with its host over a lifetime, resulting in age-related shifts in community structure and metabolic function. Little is known about whether these changes impact the community's response to microbiome-targeted therapeutics. Providing critical information on this subject, faecal microbiomes of subjects from six age groups, spanning from infancy to 70-year-old adults (n = six per age group) were harvested.
View Article and Find Full Text PDFFoods
January 2025
Key Laboratory of South Subtropical Fruit Biology and Genetic Resource Utilization, Ministry of Agriculture and Rural Affairs, Guangdong Provincial Key Laboratory of Science and Technology Research on Fruit Tree, Institute of Fruit Tree Research, Guangdong Academy of Agricultural Sciences, Guangzhou 510640, China.
Litchi is one of the ancient fruits that originated in China, renowned for its high nutrition and rich flavor, and Xianjinfeng (XJF) stands as one of the most notable varieties in terms of its flavor. Investigating the metabolic changes in taste compounds during fruit development offers deeper insights into the formation patterns of fruit quality. In this study, we conducted extensive metabonomic research on the accumulation patterns of taste compounds (carbohydrates, organic acids, and amino acids) across three developmental stages of XJF litchi.
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