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Yu ZJ, Easton MW, Murria P, Xu L, Ding D, Jiang Y, Zhang J, Kenttämaa HI. Molecular-Level Understanding of the Major Fragmentation Mechanisms of Cellulose Fast Pyrolysis: An Experimental Approach Based on Isotopically Labeled Model Compounds. J Org Chem 2019; 84:7037-7050. [PMID: 31064180 DOI: 10.1021/acs.joc.9b00723] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Evaluation of the feasibility of various mechanisms possibly involved in cellulose fast pyrolysis is challenging. Therefore, selectively 13C-labeled cellotriose, 18O-labeled cellobiose, and 13C- and 18O-doubly-labeled cellobiose were synthesized and subjected to fast pyrolysis in an atmospheric pressure chemical ionization source of a linear quadrupole ion trap/orbitrap mass spectrometer. The initial products were immediately quenched, ionized using ammonium cations, and subsequently analyzed using the mass spectrometer. The loss or retention of isotope labels upon pyrolysis unambiguously revealed three major competing mechanisms-sequential losses of glycolaldehyde/ethenediol molecules from the reducing end (the reducing-end unraveling mechanism), hydroxymethylene-assisted glycosidic bond cleavage (HAGBC mechanism), and Maccoll elimination. Important discoveries include the following: (1) Reducing-end unraveling is the predominant mechanism occurring at the reducing end; (2) Maccoll elimination facilitates the cleaving of aglyconic bonds, and it is the mechanism leading to formation of reducing carbohydrates; 3) HAGBC occurs for glycosides but not at the reducing end of cellodextrins; 4) HAGBC and water loss are the predominant reactions for fast pyrolysis of 1,6-anhydrocellodextrins; and 5) HAGBC can proceed after reducing-end unraveling but unraveling does not occur once the HAGBC reaction pathway is initiated. Moreover, hydrolysis was conclusively ruled out for fast pyrolysis of cellobiose, cellotriose, and 1,6-anhydrocellodextrins up to cellotetraosan. No radical reactions were observed.
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Affiliation(s)
- Zaikuan J Yu
- Department of Chemistry , Purdue University , West Lafayette , Indiana 47907 , United States
| | - Mckay W Easton
- Department of Chemistry , Purdue University , West Lafayette , Indiana 47907 , United States
| | - Priya Murria
- Department of Chemistry , Purdue University , West Lafayette , Indiana 47907 , United States
| | - Lan Xu
- Department of Chemistry , Purdue University , West Lafayette , Indiana 47907 , United States
| | - Duanchen Ding
- Department of Chemistry , Purdue University , West Lafayette , Indiana 47907 , United States
| | - Yuan Jiang
- Department of Chemistry , Purdue University , West Lafayette , Indiana 47907 , United States
| | - Jifa Zhang
- Department of Chemistry , Purdue University , West Lafayette , Indiana 47907 , United States
| | - Hilkka I Kenttämaa
- Department of Chemistry , Purdue University , West Lafayette , Indiana 47907 , United States
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Petermichl M, Schobert R. Total Synthesis of the Diglycosidic Tetramic Acid Ancorinoside A. Chemistry 2017; 23:14743-14746. [DOI: 10.1002/chem.201704379] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2017] [Indexed: 11/10/2022]
Affiliation(s)
- Markus Petermichl
- Department of Chemistry; University Bayreuth; Universitaetsstr. 30 95447 Bayreuth Germany
| | - Rainer Schobert
- Department of Chemistry; University Bayreuth; Universitaetsstr. 30 95447 Bayreuth Germany
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Giordano M, Iadonisi A, Pastore A. Regioselective Acetolysis of HighlyO-Benzylated Carbohydrates Promoted by Iodine or an Iodine/Silane Combined Reagent: Use of Isopropenyl Acetate as an Alternative to Acetic Anhydride. European J Org Chem 2013. [DOI: 10.1002/ejoc.201300064] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Kirkeby S, Friis M, Mikkelsen H, Cayé-Thomasen P. Bacterial adherence in otitis media: Determination of N-acetylgalactosamine (GalNAc) residues in the submucosal glands and surface epithelium of the normal and diseased Eustachian tube. Microb Pathog 2011; 51:48-57. [DOI: 10.1016/j.micpath.2011.03.008] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2010] [Revised: 03/14/2011] [Accepted: 03/16/2011] [Indexed: 10/18/2022]
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Cheaib R, Listkowski A, Chambert S, Doutheau A, Queneau Y. Synthesis of new mono- and disaccharidic carboxymethylglycoside lactones (CMGLs) and their use toward 1,2-bisfunctionalized carbohydrate synthons. ACTA ACUST UNITED AC 2008. [DOI: 10.1016/j.tetasy.2008.07.016] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Christensen H, Christiansen MS, Petersen J, Jensen HH. Direct formation of beta-glycosides of N-acetyl glycosamines mediated by rare earth metal triflates. Org Biomol Chem 2008; 6:3276-83. [PMID: 18802633 DOI: 10.1039/b807064d] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A direct, mild and efficient protocol for the preparation of beta-glycosides of N-acetyl glucosamine (GlcNAc) and N-acetyl galactosamine (GalNAc) has been developed using peracetylated beta-GlcNAc and beta-GalNAc as donors. All rare Earth metal triflate promoters screened were found to promote glycosylation with Sc(OTf)(3) being superior in terms of reaction rate. Simple alcohol glycosylation was found to proceed smoothly in refluxing dichloromethane, whereas higher temperatures under microwave conditions were needed to attain acceptable yields with less reactive, carbohydrate based glycosyl acceptors. The protocol developed was applied to provide the first example of direct chemical formation of a disaccharide using both GlcNAc as a glycosyl donor and acceptor. The alpha-acetate donor was found to be significantly less reactive than the corresponding beta-anomer necessitating higher reaction temperatures under which glycoside anomerisation was found to occur. It was established, that the anomerisation only took place in the presence of both Sc(OTf)(3) and acetic acid.
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Affiliation(s)
- Helle Christensen
- Department of Chemistry, University of Aarhus, Langelandsgade 140, DK-8000, Aarhus C, Denmark
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Pierre R, Chambert S, Alirachedi F, Danel M, Trombotto S, Doutheau A, Queneau Y. Carboxymethyl glucosides and carboxymethyl glucoside lactones: A detailed study of their preparation by oxidative degradation of disaccharides. CR CHIM 2008. [DOI: 10.1016/j.crci.2007.03.013] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Listkowski A, Ing P, Cheaib R, Chambert S, Doutheau A, Queneau Y. Carboxymethylglycoside lactones (CMGLs): structural variations on the carbohydrate moiety. ACTA ACUST UNITED AC 2007. [DOI: 10.1016/j.tetasy.2007.09.007] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Abstract
Bacterial adhesion is often a prelude to infection. In many cases, this process is governed by protein-carbohydrate interactions. Intervention at this early stage of infection is a conceptually highly attractive alternative to conventional antibiotics that are increasingly prone to resistance. The lack of high-affinity inhibitors of adhesion has proven to be a hurdle for further exploitation of this concept; however, new developments indicate a positive change. Structure-based design at the monovalent level and also evaluation of glycodendrimers and glycopolymers have yielded structures of high affinity. In addition to the development of inhibitors, topics of this review include available structural information of adhesion proteins, carbohydrate specificities of the various pathogens and their adhesion proteins. Other new developments aimed at affecting bacterial adhesion and the use of the adhesins for bacterial detection are also discussed.
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Affiliation(s)
- Roland J Pieters
- Department of Medicinal Chemistry and Chemical Biology, Utrecht Institute for Pharmaceutical Sciences, Utrecht University, NL-3508 TB Utrecht, The Netherlands.
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