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Shou K, Zhang Y, Ji Y, Liu B, Zhou Q, Tan Q, Li F, Wang X, Lu G, Xiao G. Highly stereoselective α-glycosylation with GalN 3 donors enabled collective synthesis of mucin-related tumor associated carbohydrate antigens. Chem Sci 2024; 15:6552-6561. [PMID: 38699257 PMCID: PMC11062124 DOI: 10.1039/d4sc01348d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2024] [Accepted: 04/01/2024] [Indexed: 05/05/2024] Open
Abstract
Mucin-related tumor-associated carbohydrate antigens (TACAs) are important and interesting targets for cancer vaccine therapy. However, efficient access to a library of mucin-related TACAs remains a challenging task. One of the key issues is the challenging construction of α-GalNAc linkages. Here, we report highly stereoselective α-glycosylation with GalN3N-phenyl trifluoroacetimidate donors, which features excellent yields, outstanding stereoselectivities, broad substrate scope and mild reaction conditions. This method is successfully applied to highly stereoselective synthesis of GalN3-α-O-Ser, which served as the common intermediate for collective synthesis of a wide range of TACAs including TN antigen, STN antigen, 2,6 STF antigen, 2,3 STF antigen, glycophorin and cores 1-8 mucin-type O-glycans. In particular, the rationale for this highly stereoselective α-glycosylation is provided for the first time using DFT calculations and mechanistic studies, highlighting the crucial roles of reagent combinations (TMSI and Ph3PO) and the H-bonding directing effect of the N3 group.
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Affiliation(s)
- Kunxiu Shou
- State Key Laboratory of Phytochemistry and Natural Medicines, Kunming Institute of Botany, University of Chinese Academy of Sciences, Chinese Academy of Sciences 132 Lanhei Road Kunming 650201 China
| | - Yunqin Zhang
- State Key Laboratory of Phytochemistry and Natural Medicines, Kunming Institute of Botany, University of Chinese Academy of Sciences, Chinese Academy of Sciences 132 Lanhei Road Kunming 650201 China
| | - Yujie Ji
- School of Chemistry and Chemical Engineering, Shandong University Jinan Shandong 250100 China
| | - Bin Liu
- State Key Laboratory of Phytochemistry and Natural Medicines, Kunming Institute of Botany, University of Chinese Academy of Sciences, Chinese Academy of Sciences 132 Lanhei Road Kunming 650201 China
| | - Qingli Zhou
- State Key Laboratory of Phytochemistry and Natural Medicines, Kunming Institute of Botany, University of Chinese Academy of Sciences, Chinese Academy of Sciences 132 Lanhei Road Kunming 650201 China
| | - Qiang Tan
- State Key Laboratory of Phytochemistry and Natural Medicines, Kunming Institute of Botany, University of Chinese Academy of Sciences, Chinese Academy of Sciences 132 Lanhei Road Kunming 650201 China
| | - Fuying Li
- Department of Chemistry, Kunming University 2 Puxing Road Kunming 650214 China
| | - Xiufang Wang
- Department of Chemistry, Kunming University 2 Puxing Road Kunming 650214 China
| | - Gang Lu
- School of Chemistry and Chemical Engineering, Shandong University Jinan Shandong 250100 China
| | - Guozhi Xiao
- State Key Laboratory of Phytochemistry and Natural Medicines, Kunming Institute of Botany, University of Chinese Academy of Sciences, Chinese Academy of Sciences 132 Lanhei Road Kunming 650201 China
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Yang J, Xie D, Ma X. Recent Advances in Chemical Synthesis of Amino Sugars. Molecules 2023; 28:4724. [PMID: 37375279 DOI: 10.3390/molecules28124724] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2023] [Revised: 06/06/2023] [Accepted: 06/07/2023] [Indexed: 06/29/2023] Open
Abstract
Amino sugars are a kind of carbohydrates with one or more hydroxyl groups replaced by an amino group. They play crucial roles in a broad range of biological activities. Over the past few decades, there have been continuing efforts on the stereoselective glycosylation of amino sugars. However, the introduction of glycoside bearing basic nitrogen is challenging using conventional Lewis acid-promoted pathways owing to competitive coordination of the amine to the Lewis acid promoter. Additionally, diastereomeric mixtures of O-glycoside are often produced if aminoglycoside lack a C2 substituent. This review focuses on the updated overview of the way to stereoselective synthesis of 1,2-cis-aminoglycoside. The scope, mechanism, and the applications in the synthesis of complex glycoconjugates for the representative methodologies were also included.
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Affiliation(s)
- Jian Yang
- Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Demeng Xie
- Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041, China
| | - Xiaofeng Ma
- Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041, China
- University of Chinese Academy of Sciences, Beijing 100049, China
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Zhu S, Li J, Loka RS, Song Z, Vlodavsky I, Zhang K, Nguyen HM. Modulating Heparanase Activity: Tuning Sulfation Pattern and Glycosidic Linkage of Oligosaccharides. J Med Chem 2020; 63:4227-4255. [PMID: 32216347 DOI: 10.1021/acs.jmedchem.0c00156] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Heparanase cleaves polymeric heparan sulfate (HS) molecules into smaller oligosaccharides, allowing for release of angiogenic growth factors promoting tumor development and autoreactive immune cells to reach the insulin-producing β cells. Interaction of heparanase with HS chains is regulated by specific substrate sulfation sequences. We have synthesized 11 trisaccharides that are highly tunable in structure and sulfation pattern, allowing us to determine how heparanase recognizes HS substrate and selects a favorable cleavage site. Our study shows that (1) N-SO3- at +1 subsite and 6-O-SO3- at -2 subsite of trisaccharides are critical for heparanase recognition, (2) addition of 2-O-SO3- at the -1 subsite and of 3-O-SO3- to GlcN unit is not advantageous, and (3) the anomeric configuration (α or β) at the reducing end is crucial in controlling heparanase activity. Our study also illustrates that the α-trisaccharide having N- and 6-O-SO3- at -2 and +1 subsites inhibited heparanase and was resistant toward hydrolysis.
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Affiliation(s)
- Sanyong Zhu
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202, United States
| | - Jiayi Li
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202, United States
| | - Ravi S Loka
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202, United States
| | - Zhenfeng Song
- Center for Molecular Medicine and Genetics, Wayne State University School of Medicine, Detroit, Michigan 48201, United States
| | - Israel Vlodavsky
- Cancer and Vascular Biology Research Center, Rappaport Faculty of Medicine, Technion, Haifa 31096, Israel
| | - Kezhong Zhang
- Center for Molecular Medicine and Genetics, Wayne State University School of Medicine, Detroit, Michigan 48201, United States
| | - Hien M Nguyen
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202, United States
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Sletten ET, Tu YJ, Schlegel HB, Nguyen HM. Are Brønsted Acids the True Promoter of Metal-Triflate-Catalyzed Glycosylations? A Mechanistic Probe into 1,2- cis-Aminoglycoside Formation by Nickel Triflate. ACS Catal 2019; 9:2110-2123. [PMID: 31819822 PMCID: PMC6900934 DOI: 10.1021/acscatal.8b04444] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Metal triflates have been utilized to catalytically facilitate numerous glycosylation reactions under mild conditions. In some methods, the metal triflate system provides stereocontrol during the glycosylation, rather than the nature of protecting groups on the substrate. Despite these advances, the true activating nature of metal triflates remains unclear. Our findings indicated that the in situ generation of trace amounts of triflic acid from metal triflates can be the active catalyst species in the glycosylation. This fact has been mentioned previously in metal triflate-catalyzed glycosylation reactions; however, a thorough study on the subject and its implications on stereoselectivity has yet to be performed. Experimental evidence from control reactions and 19F NMR spectroscopy have been obtained to confirm and quantify the triflic acid released from nickel triflate, for which it is of paramount importance in achieving a stereoselective 1,2-cis-2-amino glycosidic bond formation via a transient anomeric triflate. A putative intermediate resembling that of a glycosyl triflate has been detected using variable temperature NMR (1H and 13C) experiments. These observations, together with density functional theory calculations and a kinetic study, corroborate a mechanism involving triflic acid-catalyzed stereoselective glycosylation with N-substituted trifluoromethylbenzylideneamino protected electrophiles. Specifically, triflic acid facilitates formation of a glycosyl triflate intermediate which then undergoes isomerization from the stable α-anomer to the more reactive β-anomer. Subsequent SN2-like displacement of the reactive anomer by a nucleophile is highly favorable for the production of 1,2-cis-2-aminoglycosides. Although there is a previously reported work regarding glycosyl triflates, none of these reports have been confirmed to come from the counter ion of the metal center. Our work provides supporting evidence for the induction of a glycosyl triflate through the role of triflic acid in metal triflate-catalyzed glycosylation reactions.
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Affiliation(s)
- Eric T Sletten
- Department of Chemistry, University of Iowa, Iowa City, Iowa 52242, United Sates
| | - Yi-Jung Tu
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202, United States
| | - H Bernhard Schlegel
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202, United States
| | - Hien M Nguyen
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202, United States
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Affiliation(s)
- Michael Martin Nielsen
- Department of Chemistry, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen, Denmark
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Manabe S, Ito Y. Comparing of endocyclic and exocyclic cleavage reactions using mycothiol synthesis as an example. Tetrahedron 2018. [DOI: 10.1016/j.tet.2018.03.069] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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Abstract
AbstractExistence of endocyclic cleavage reaction is now clearly shown from experimental evidence of endocyclic cleavage reaction as well as computational chemistry. Not only stereoelectronic factor, several factors could be main factors for endocyclic cleavage reaction. Endocyclic cleavage reaction is useful for 1,2-cis aminoglycoside formation, which is difficult by conventional glycosylation. By using endocyclic cleavage reaction, several glycosides with 1,2-cis aminoglycoside were prepared.
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Affiliation(s)
- Shino Manabe
- RIKEN, Synthetic Cellular Chemistry Laboratory, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Yukishige Ito
- RIKEN, Synthetic Cellular Chemistry Laboratory, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
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Sletten ET, Ramadugu SK, Nguyen HM. Utilization of bench-stable and readily available nickel(II) triflate for access to 1,2-cis-2-aminoglycosides. Carbohydr Res 2016; 435:195-207. [PMID: 27816838 DOI: 10.1016/j.carres.2016.10.008] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2016] [Revised: 10/10/2016] [Accepted: 10/20/2016] [Indexed: 10/20/2022]
Abstract
The utilization of substoichiometric amounts of commercially available nickel(II) triflate as an activator in the reagent-controlled glycosylation reaction for the stereoselective construction of biologically relevant targets containing 1,2-cis-2-amino glycosidic linkages is reported. This straightforward and accessible methodology is mild, operationally simple and safe through catalytic activation by readily available Ni(OTf)2 in comparison to systems employing our previously in-house prepared Ni(4-F-PhCN)4(OTf)2. We anticipate that the bench-stable and inexpensive Ni(OTf)2, coupled with little to no extra laboratory training to set up the glycosylation reaction and no requirement of specialized equipment, should make this methodology be readily adopted by non-carbohydrate specialists. This report further highlights the efficacy of Ni(OTf)2 to prepare several bioactive motifs, such as blood type A-type V and VI antigens, heparin sulfate disaccharide repeating unit, aminooxy glycosides, and α-GalNAc-Serine conjugate, which cannot be achieved in high yield and α-selectivity utilizing in-house prepared Ni(4-F-PhCN)4(OTf)2 catalyst. The newly-developed protocol eliminates the need for the synthesis of Ni(4-F-PhCN)4(OTf)2 and is scalable and reproducible. Furthermore, computational simulations in combination with 1H NMR studies analyzed the effects of various solvents on the intramolecular hydrogen bonding network of tumor-associated mucin Fmoc-protected GalNAc-threonine amino acid antigen derivative, verifying discrepancies found that were previously unreported.
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Affiliation(s)
- Eric T Sletten
- Department of Chemistry, University of Iowa, Iowa City, 52242, USA
| | | | - Hien M Nguyen
- Department of Chemistry, University of Iowa, Iowa City, 52242, USA.
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Li X, Zhu J. Glycosylation via Transition-Metal Catalysis: Challenges and Opportunities. European J Org Chem 2016. [DOI: 10.1002/ejoc.201600484] [Citation(s) in RCA: 71] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Xiaohua Li
- Department of Natural Sciences; University of Michigan-Dearborn; 4901 Evergreen Road 48128 Dearborn Michigan USA
| | - Jianglong Zhu
- Department of Chemistry and Biochemistry and School of Green Chemistry and Engineering; The University of Toledo; 2801 West Bancroft Street 43606 Toledo Ohio USA
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Zhang K, Xu XH, Qing FL. Copper-Promoted Ritter-Type Trifluoroethoxylation of (Hetero)arenediazonium Tetrafluoroborates: A Method for the Preparation of Trifluoroethyl Imidates. European J Org Chem 2016. [DOI: 10.1002/ejoc.201600941] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- Ke Zhang
- College of Chemistry, Chemical Engineering and Biotechnology; Donghua University; 2999 North Renmin Lu 201620 Shanghai P. R. China
| | - Xiu-Hua Xu
- Key Laboratory of Organofluorine Chemistry; Shanghai Institute of Organic Chemistry; Chinese Academy of Science; 345 Lingling Lu 200032 Shanghai P. R. China
| | - Feng-Ling Qing
- College of Chemistry, Chemical Engineering and Biotechnology; Donghua University; 2999 North Renmin Lu 201620 Shanghai P. R. China
- Key Laboratory of Organofluorine Chemistry; Shanghai Institute of Organic Chemistry; Chinese Academy of Science; 345 Lingling Lu 200032 Shanghai P. R. China
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Manabe S, Ito Y. Mycothiol synthesis by an anomerization reaction through endocyclic cleavage. Beilstein J Org Chem 2016; 12:328-33. [PMID: 26977192 PMCID: PMC4778527 DOI: 10.3762/bjoc.12.35] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2015] [Accepted: 02/11/2016] [Indexed: 11/23/2022] Open
Abstract
Mycothiol is found in Gram-positive bacteria, where it helps in maintaining a reducing intracellular environment and it plays an important role in protecting the cell from toxic chemicals. The inhibition of the mycothiol biosynthesis is considered as a treatment for tuberculosis. Mycothiol contains an α-aminoglycoside, which is difficult to prepare stereoselectively by a conventional glycosylation reaction. In this study, mycothiol was synthesized by an anomerization reaction from an easily prepared β-aminoglycoside through endocyclic cleavage.
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Affiliation(s)
- Shino Manabe
- Synthetic Cellular Chemistry Lab, RIKEN, Hirosawa, Wako, Saitama 351-0198, Japan
| | - Yukishige Ito
- Synthetic Cellular Chemistry Lab, RIKEN, Hirosawa, Wako, Saitama 351-0198, Japan
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Peng P, Schmidt RR. An Alternative Reaction Course in O-Glycosidation with O-Glycosyl Trichloroacetimidates as Glycosyl Donors and Lewis Acidic Metal Salts as Catalyst: Acid–Base Catalysis with Gold Chloride-Glycosyl Acceptor Adducts. J Am Chem Soc 2015; 137:12653-9. [DOI: 10.1021/jacs.5b07895] [Citation(s) in RCA: 79] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Peng Peng
- Department of Chemistry, University of Konstanz, D-78457 Konstanz, Germany
| | - Richard R. Schmidt
- Department of Chemistry, University of Konstanz, D-78457 Konstanz, Germany
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Abstract
A synthetic study on the creation of a bivalent, ROMP capable monomer has the ability to be polymerized into the corresponding neo-glycopolymer mimetic of the surface glycans on gp120 envelope spike of the HIV virus. In our approach, we have developed a new strategy for orthogonally attaching both the terminal Manα1-2Man disaccharide unit of the D1 arm of Man9GlcNAc2 of HIV gp120 and the terminal Manα1-2 unit of its D2 arm to a bivalent scaffold to produce the corresponding polymerizable monomer. The Manα1-2 saccharide moieties were assembled using a nickel catalyst, Ni(4-F-PhCN)4(OTf)2, to activate trihaloacetimidate donors under mild and operationally simple procedure.
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Yu F, McConnell MS, Nguyen HM. Scalable synthesis of Fmoc-protected GalNAc-threonine amino acid and T(N) antigen via nickel catalysis. Org Lett 2015; 17:2018-21. [PMID: 25853273 PMCID: PMC4752204 DOI: 10.1021/acs.orglett.5b00780] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The highly α-selective and scalable synthesis of the Fmoc-protected GalNAc-threonine amino acid and TN antigen in gram scale (0.5-1 g) is described. The challenging 1,2-cis-2-amino glycosidic bond is addressed through a coupling of threonine residues with C(2)-N-ortho-(trifluoromethyl)benzylidenamino trihaloacetimidate donors mediated by Ni(4-F-PhCN)4(OTf)2. The desired 1,2-cis-2-amino glycoside was obtained in 66% yield (3.77 g) with α-only selectivity and subsequently transformed into the Fmoc-protected GalNAc-threonine and TN antigen. This operationally simple procedure no longer requires utilization of the commonly used C(2)-azido donors and overcomes many of the limitations associated with the synthesis of 1,2-cis linkage.
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Affiliation(s)
| | | | - Hien M. Nguyen
- Department of Chemistry, University of Iowa, Iowa City, Iowa 52242, United States
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McKay MJ, Park NH, Nguyen HM. Investigations of scope and mechanism of nickel-catalyzed transformations of glycosyl trichloroacetimidates to glycosyl trichloroacetamides and subsequent, atom-economical, one-step conversion to α-urea-glycosides. Chemistry 2014; 20:8691-701. [PMID: 24905328 DOI: 10.1002/chem.201402433] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2014] [Indexed: 12/13/2022]
Abstract
The development and mechanistic investigation of a highly stereoselective methodology for preparing α-linked-urea neo-glycoconjugates and pseudo-oligosaccharides is described. This two-step procedure begins with the selective nickel-catalyzed conversion of glycosyl trichloroacetimidates to the corresponding α-trichloroacetamides. The α-selective nature of the conversion is controlled with a cationic nickel(II) catalyst, [Ni(dppe)(OTf)2 ] (dppe=1,2-bis(diphenylphosphino)ethane, OTf=triflate). Mechanistic studies have identified the coordination of the nickel catalyst with the equatorial C2 -ether functionality of the α-glycosyl trichloroacetimidate to be paramount for achieving an α-stereoselective transformation. A cross-over experiment has indicated that the reaction does not proceed in an exclusively intramolecular fashion. The second step in this sequence is the direct conversion of α-glycosyl trichloroacetamide products into the corresponding α-urea glycosides by reacting them with a wide variety of amine nucleophiles in presence of cesium carbonate. Only α-urea-product formation is observed, as the reaction proceeds with complete retention of stereochemical integrity at the anomeric CN bond.
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Affiliation(s)
- Matthew J McKay
- Department of Chemistry, University of Iowa, Iowa City, Iowa, 52242 (USA), Fax: (+1) 319-335-1270
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McConnell MS, Mensah EA, Nguyen HM. Stereoselective α-glycosylation of C(6)-hydroxyl myo-inositols via nickel catalysis-application to the synthesis of GPI anchor pseudo-oligosaccharides. Carbohydr Res 2013; 381:146-52. [PMID: 24121123 DOI: 10.1016/j.carres.2013.09.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2013] [Revised: 09/06/2013] [Accepted: 09/14/2013] [Indexed: 10/26/2022]
Abstract
Glycosylphosphatidyl inositol (GPI) anchors play a key role in many eukaryotic biological pathways. Stereoselective synthesis of GPI anchor analogues have proven to be critical for probing the biosynthesis, structure, and biological properties of these compounds. Challenges that have emerged from these efforts include the preparation of the selectively protected myo-inositol building blocks and the stereoselective construction of glucosamine α-linked myo-inositol containing pseudodisaccharide units. Herein, we describe the effectiveness of the cationic nickel(II) catalyst, Ni(4-F-PhCN)4(OTf)2, at promoting selective formation of 1,2-cis-2-amino glycosidic bonds between the C(2)-N-substituted benzylideneamino trihaloacetimidate donors and C(6)-hydroxyl myo-inositol acceptors. This catalytic coupling process allows rapid access to pseudosaccharides of GPI anchors in good yields and with excellent levels of α-selectivity (α:β=10:1-20:1). In stark contrast, activation of trichloroacetimidate donors containing the C(2)-N-substituted benzylidene group with TMSOTf and BF3(.)OEt2 provided the desired pseudodisaccharides as a 1:1 mixture of α- and β-isomers.
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Affiliation(s)
- Matthew S McConnell
- Department of Chemistry, University of Iowa, Iowa City, IA 52242, United States
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