1
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Yang X, Zhang H, Zhao Q, Li Q, Li T, Gao J. Total Synthesis of the Repeating Units of Highly Functionalized O-Antigens of Pseudomonas aeruginosa ATCC 27577, O10, and O19. JACS AU 2024; 4:2351-2362. [PMID: 38938791 PMCID: PMC11200240 DOI: 10.1021/jacsau.4c00321] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/09/2024] [Revised: 05/24/2024] [Accepted: 05/29/2024] [Indexed: 06/29/2024]
Abstract
The first total synthesis of the repeating units of the O-antigens of Pseudomonas aeruginosa ATCC 27577, O10, and O19 was achieved via a linear glycosylation strategy. This also represents the first synthesis of an oligosaccharide containing an α-linked N-acetyl-l-galactosaminuronic acid (l-GalpNAcA) unit. All of the glycosyl linkages, including three challenging 1,2-cis-glycosidic bonds of amino sugars, were effectively constructed with high to exclusive stereoselectivity, while orthogonal protection tactics were employed to facilitate regioselective glycosylations and the introduction of a variety of functionalities. An acetyl group migration phenomenon was found during the synthesis of the O-acylated repeating unit of the P. aeruginosa ATCC 27577 antigen. All synthetic targets carried an amino functional group in the linker at the reducing end, thus facilitating further regioselective elaboration and biological studies. The synthetic strategy established here should be useful for the preparation of other similar oligosaccharides.
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Affiliation(s)
- Xiaoyu Yang
- National
Glycoengineering Research Center, Shandong Key Laboratory of Carbohydrate
Chemistry and Glycobiology, Shandong University, Qingdao ,Shandong 266237, China
- NMPA
Key Laboratory for Quality Research and Evaluation of Carbohydrate-Based
Medicine, Shandong University, Qingdao ,Shandong 266237, China
| | - Han Zhang
- Department
of Pharmacy, Shandong University of Traditional
Chinese Medicine, Jinan ,Shandong 250355, China
| | - Qingpeng Zhao
- National
Glycoengineering Research Center, Shandong Key Laboratory of Carbohydrate
Chemistry and Glycobiology, Shandong University, Qingdao ,Shandong 266237, China
- NMPA
Key Laboratory for Quality Research and Evaluation of Carbohydrate-Based
Medicine, Shandong University, Qingdao ,Shandong 266237, China
| | - Qingjiang Li
- Department
of Chemistry, University of Massachusetts
Boston, 100 Morrissey Boulevard, Boston, Massachusetts 02125, United States
| | - Tiehai Li
- State
Key Laboratory of Chemical Biology, Shanghai Institute of Materia
Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Jian Gao
- National
Glycoengineering Research Center, Shandong Key Laboratory of Carbohydrate
Chemistry and Glycobiology, Shandong University, Qingdao ,Shandong 266237, China
- NMPA
Key Laboratory for Quality Research and Evaluation of Carbohydrate-Based
Medicine, Shandong University, Qingdao ,Shandong 266237, China
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2
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Mettu R, Cheng YY, Vulupala HR, Lih YH, Chen CY, Hsu MH, Lo HJ, Liao KS, Chiu CH, Wu CY. Chemical Synthesis of Truncated Capsular Oligosaccharide of Serotypes 6C and 6D of Streptococcus pneumoniae with Their Immunological Studies. ACS Infect Dis 2024; 10:2161-2171. [PMID: 38770797 PMCID: PMC11184553 DOI: 10.1021/acsinfecdis.4c00147] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2024] [Revised: 05/04/2024] [Accepted: 05/06/2024] [Indexed: 05/22/2024]
Abstract
Serotypes 6C and 6D of Streptococcus pneumoniae are two major variants that cause invasive pneumococcal disease (IPD) in serogroup 6 alongside serotypes 6A and 6B. Since the introduction of the pneumococcal conjugate vaccines PCV7 and PCV13, the number of cases of IPD caused by pneumococcus in children and the elderly population has greatly decreased. However, with the widespread use of vaccines, a replacement effect has recently been observed among different serotypes and lowered the effectiveness of the vaccines. To investigate protection against the original serotypes and to explore protection against variants and replacement serotypes, we created a library of oligosaccharide fragments derived from the repeating units of the capsular polysaccharides of serotypes 6A, 6B, 6C, and 6D through chemical synthesis. The library includes nine pseudosaccharides with or without exposed terminal phosphate groups and four pseudotetrasaccharides bridged by phosphate groups. Six carbohydrate antigens related to 6C and 6D were prepared as glycoprotein vaccines for immunogenicity studies. Two 6A and two 6B glycoconjugate vaccines from previous studies were included in immunogenicity studies. We found that the conjugates containing four phosphate-bridged pseudotetrasaccharides were able to induce good immune antibodies and cross-immunogenicity by showing superior activity and broad cross-protective activity in OPKA bactericidal experiments.
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Affiliation(s)
- Ravinder Mettu
- Genomics
Research Center, Academia Sinica, 128 Academia Road, Section 2, Nankang, Taipei 11529, Taiwan
| | - Yang-Yu Cheng
- Genomics
Research Center, Academia Sinica, 128 Academia Road, Section 2, Nankang, Taipei 11529, Taiwan
- Institute
of Biochemistry and Molecular Biology, National
Yang Ming Chiao Tung University, No. 155, Section 2, Linong Street, Taipei 112304, Taiwan
| | - Hanmanth Reddy Vulupala
- Genomics
Research Center, Academia Sinica, 128 Academia Road, Section 2, Nankang, Taipei 11529, Taiwan
| | - Yu-Hsuan Lih
- Genomics
Research Center, Academia Sinica, 128 Academia Road, Section 2, Nankang, Taipei 11529, Taiwan
| | - Chiang-Yun Chen
- Genomics
Research Center, Academia Sinica, 128 Academia Road, Section 2, Nankang, Taipei 11529, Taiwan
| | - Mei-Hua Hsu
- Molecular
Infectious Disease Research Center, Chang Gung Memorial Hospital, Chang Gung University College of Medicine, 259 Wenhua First Road, Guishan, Taoyuan 33302, Taiwan
| | - Hong-Jay Lo
- Genomics
Research Center, Academia Sinica, 128 Academia Road, Section 2, Nankang, Taipei 11529, Taiwan
| | - Kuo-Shiang Liao
- Genomics
Research Center, Academia Sinica, 128 Academia Road, Section 2, Nankang, Taipei 11529, Taiwan
| | - Cheng-Hsun Chiu
- Molecular
Infectious Disease Research Center, Chang Gung Memorial Hospital, Chang Gung University College of Medicine, 259 Wenhua First Road, Guishan, Taoyuan 33302, Taiwan
| | - Chung-Yi Wu
- Genomics
Research Center, Academia Sinica, 128 Academia Road, Section 2, Nankang, Taipei 11529, Taiwan
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3
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Yao W, Ye XS. Donor Preactivation-Based Glycan Assembly: from Manual to Automated Synthesis. Acc Chem Res 2024; 57:1577-1594. [PMID: 38623919 DOI: 10.1021/acs.accounts.4c00072] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/17/2024]
Abstract
Carbohydrates are called the third chain of life. Carbohydrates participate in many important biochemical functions in living species, and the biological information carried by them is several orders of magnitude larger than that of nucleic acids and proteins. However, due to the intrinsic complexity and heterogeneity of carbohydrate structures, furnishing pure and structurally well-defined glycans for functional studies is a formidable task, especially for homogeneous large-size glycans. To address this issue, we have developed a donor preactivation-based one-pot glycosylation strategy enabling multiple sequential glycosylations in a single reaction vessel.The donor preactivation-based one-pot glycosylation refers to the strategy in which the glycosyl donor is activated in the absence of a glycosyl acceptor to generate a reactive intermediate. Subsequently, the glycosyl acceptor with the same anomeric leaving group is added, leading to a glycosyl coupling reaction, which is then iterated to rapidly achieve the desired glycan in the same reactor. The advantages of this strategy include the following: (1) unique chemoselectivity is obtained after preactivation; (2) it is independent of the reactivity of glycosyl donors; (3) multiple-step glycosylations are enabled without the need for intermediate purification; (4) only stoichiometric building blocks are required without complex protecting group manipulations. Using this protocol, a range of glycans including tumor-associated carbohydrate antigens, various glycosaminoglycans, complex N-glycans, and diverse bacterial glycans have been synthesized manually. Gratifyingly, the synthesis of mycobacterial arabinogalactan containing 92 monosaccharide units has been achieved, which created a precedent in the field of polysaccharide synthesis. Recently, the synthesis of a highly branched arabinogalactan from traditional Chinese medicine featuring 140 monosaccharide units has been also accomplished to evaluate its anti-pancreatic-cancer activity. In the spirit of green and sustainable chemistry, this strategy can also be applied to light-driven glycosylation reactions, where either UV or visible light can be used for the activation of glycosyl donors.Automated synthesis is an advanced approach to the construction of complex glycans. Based on the two preactivation modes (general promoter activation mode and light-induced activation mode), a universal and highly efficient automated solution-phase synthesizer was further developed to drive glycan assembly from manual to automated synthesis. Using this synthesizer, a library of oligosaccharides covering various glycoforms and glycosidic linkages was assembled rapidly, either in a general promoter-activation mode or in a light-induced-activation mode. The automated synthesis of a fully protected fondaparinux pentasaccharide was realized on a gram scale. Furthermore, the automated synthesis of large-size polysaccharides was performed, allowing the assembly of arabinans up to an astonishing 1080-mer using the automated multiplicative synthesis strategy, taking glycan synthesis to a new height far beyond the synthesis of nucleic acids (up to 200-mer) and proteins (up to 472-mer).
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Affiliation(s)
- Wenlong Yao
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, and Chemical Biology Center, Peking University, Xue Yuan Road No. 38, Beijing 100191, China
| | - Xin-Shan Ye
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, and Chemical Biology Center, Peking University, Xue Yuan Road No. 38, Beijing 100191, China
- National Research Center for Carbohydrate Synthesis, Jiangxi Normal University, Nanchang 330022, China
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4
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Gao Y, Chen W, Zhao J, Yang M, Zhang Y, Chen C, Yao L, Xu J, Wang F, Zhang B, Gu G, Tang B, Cai F. Exploring the Dual Functions of Distal Acyl Group Direction in Various Nucleophilic Environments. J Org Chem 2024; 89:2375-2396. [PMID: 38288704 DOI: 10.1021/acs.joc.3c02397] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2024]
Abstract
A universal glycosylation strategy could significantly simplify glycoside synthesis. One approach to achieving this goal is through acyl group direction for the corresponding 1,2-, 1,3-, 1,4-, or 1,6-trans glycosylation; however, this approach has been challenging for glycosidic bonds that require distal equatorial-acyl group direction. We developed an approach in weakly nucleophilic environments for selective 1,4-trans glycosylation directed by the equatorial-4-O-acyl group. Here, we explored this condition in other distal acyl groups and found that, besides 1,n-trans direction, acyl groups also mediated hydrogen bonding between acyl groups and alcohols. The latter showed a diverse effect and classified the acyl group direction into axial and equatorial categories. Corresponding glycosylation conditions were distinguished as guidance for acyl group direction from either category. Hence, acyl group direction may serve as a general glycosylation strategy.
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Affiliation(s)
- Yongtao Gao
- National Glycoengineering Research Center and Shandong Key Laboratory of Carbohydrate Chemistry and Glycobiology, Shandong University, 72 Binhai Rd, Qingdao 266237, China
| | - Wenjie Chen
- National Glycoengineering Research Center and Shandong Key Laboratory of Carbohydrate Chemistry and Glycobiology, Shandong University, 72 Binhai Rd, Qingdao 266237, China
| | - Juan Zhao
- National Glycoengineering Research Center and Shandong Key Laboratory of Carbohydrate Chemistry and Glycobiology, Shandong University, 72 Binhai Rd, Qingdao 266237, China
| | - Min Yang
- Center for Analysis and Characterization, School of Physical Science and Technology, ShanghaiTech University, 393 Huaxia Middle Rd, Shanghai 201210, China
| | - Yongliang Zhang
- National Glycoengineering Research Center and Shandong Key Laboratory of Carbohydrate Chemistry and Glycobiology, Shandong University, 72 Binhai Rd, Qingdao 266237, China
| | - Changsheng Chen
- National Glycoengineering Research Center and Shandong Key Laboratory of Carbohydrate Chemistry and Glycobiology, Shandong University, 72 Binhai Rd, Qingdao 266237, China
| | - Linbin Yao
- Faculty of Science and Engineering, The University of Nottingham Ningbo China, 199 Taikang E Rd, Ningbo 315100, China
| | - Jiayuan Xu
- Faculty of Science and Engineering, The University of Nottingham Ningbo China, 199 Taikang E Rd, Ningbo 315100, China
| | - Fei Wang
- National Glycoengineering Research Center and Shandong Key Laboratory of Carbohydrate Chemistry and Glycobiology, Shandong University, 72 Binhai Rd, Qingdao 266237, China
| | - Bangzhi Zhang
- Key Laboratory of Preclinical Study for New Drugs of Gansu Province, School of Basic Medical Sciences, Lanzhou University, Lanzhou 730000, China
| | - Guofeng Gu
- National Glycoengineering Research Center and Shandong Key Laboratory of Carbohydrate Chemistry and Glycobiology, Shandong University, 72 Binhai Rd, Qingdao 266237, China
| | - Bencan Tang
- Faculty of Science and Engineering, The University of Nottingham Ningbo China, 199 Taikang E Rd, Ningbo 315100, China
| | - Feng Cai
- National Glycoengineering Research Center and Shandong Key Laboratory of Carbohydrate Chemistry and Glycobiology, Shandong University, 72 Binhai Rd, Qingdao 266237, China
- Key Laboratory of Preclinical Study for New Drugs of Gansu Province, School of Basic Medical Sciences, Lanzhou University, Lanzhou 730000, China
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5
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Ma Z, Hu Y, Li X, Liu R, Xia E, Xu P, Yang Y. Stereoselective synthesis of α-glucosides with glucosyl (Z)-Ynenoates as donors. Carbohydr Res 2023; 523:108710. [PMID: 36370627 DOI: 10.1016/j.carres.2022.108710] [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: 09/10/2022] [Revised: 10/21/2022] [Accepted: 10/26/2022] [Indexed: 11/11/2022]
Abstract
A SPhosAuNTf2-promoted DMF-modulated glycosylation approach with glycosyl (Z)-ynenoates as donors was developed for highly α-selective synthesis of various linkage types of α-glucans. The substituent groups were also found to play a significant role in the α-selective glucosylation reactions. The glycosylation approach was effectively applied to the stereospecific synthesis of the α-1,6-linked triglucoside.
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Affiliation(s)
- Zhi Ma
- Shanghai Frontiers Science Center of Optogenetic Techniques for Cell Metabolism, Shanghai Key Laboratory of New Drug Design, Engineering Research Center of Pharmaceutical Process Chemistry, Ministry of Education, School of Pharmacy, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, China
| | - Yi Hu
- Shanghai Frontiers Science Center of Optogenetic Techniques for Cell Metabolism, Shanghai Key Laboratory of New Drug Design, Engineering Research Center of Pharmaceutical Process Chemistry, Ministry of Education, School of Pharmacy, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, China
| | - Xiaona Li
- Shanghai Frontiers Science Center of Optogenetic Techniques for Cell Metabolism, Shanghai Key Laboratory of New Drug Design, Engineering Research Center of Pharmaceutical Process Chemistry, Ministry of Education, School of Pharmacy, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, China
| | - Rongkun Liu
- Shanghai Frontiers Science Center of Optogenetic Techniques for Cell Metabolism, Shanghai Key Laboratory of New Drug Design, Engineering Research Center of Pharmaceutical Process Chemistry, Ministry of Education, School of Pharmacy, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, China
| | - E Xia
- Shanghai Frontiers Science Center of Optogenetic Techniques for Cell Metabolism, Shanghai Key Laboratory of New Drug Design, Engineering Research Center of Pharmaceutical Process Chemistry, Ministry of Education, School of Pharmacy, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, China
| | - Peng Xu
- State Key Laboratory of Bioorganic and Natural Products Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai, 200032, China
| | - You Yang
- Shanghai Frontiers Science Center of Optogenetic Techniques for Cell Metabolism, Shanghai Key Laboratory of New Drug Design, Engineering Research Center of Pharmaceutical Process Chemistry, Ministry of Education, School of Pharmacy, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, China.
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6
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Zhao Q, Zhou S, Wang Y, Yang X, Meng Y, Zhang Y, Gao J. Stereoselective synthesis of the 3,6-branched Fuzi α-glucans up to 15-mer via a one-pot and convergent glycosylation strategy. CHINESE CHEM LETT 2022. [DOI: 10.1016/j.cclet.2022.107982] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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7
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Shadrick M, Stine KJ, Demchenko AV. Expanding the scope of stereoselective α-galactosylation using glycosyl chlorides. Bioorg Med Chem 2022; 73:117031. [PMID: 36202065 PMCID: PMC9677435 DOI: 10.1016/j.bmc.2022.117031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2022] [Revised: 09/19/2022] [Accepted: 09/20/2022] [Indexed: 11/20/2022]
Abstract
Recently, we reported that silver(I) oxide mediated Koenigs-Knorr glycosylation reaction can be dramatically accelerated in the presence of catalytic acid additives. We have also investigated how well this reaction works in application to differentially protected galactosyl bromides. Reported herein is the stereoselective synthesis of α-galactosides with galactosyl chlorides as glycosyl donors. Chlorides are easily accessible, stable, and can be efficiently activated for glycosylation. In this application, the most favorable reactions conditions comprised cooperative Ag2SO4 and Bi(OTf)3 promoter system.
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Affiliation(s)
- Melanie Shadrick
- Department of Chemistry, Saint Louis University, 3501 Laclede Ave, St. Louis, MO 63103, USA; Department of Chemistry and Biochemistry, University of Missouri - St. Louis, One University Boulevard, St. Louis, MO 63121, USA
| | - Keith J Stine
- Department of Chemistry and Biochemistry, University of Missouri - St. Louis, One University Boulevard, St. Louis, MO 63121, USA
| | - Alexei V Demchenko
- Department of Chemistry, Saint Louis University, 3501 Laclede Ave, St. Louis, MO 63103, USA; Department of Chemistry and Biochemistry, University of Missouri - St. Louis, One University Boulevard, St. Louis, MO 63121, USA.
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8
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Inuki S, Tabuchi H, Matsuzaki C, Yonejima Y, Hisa K, Kimura I, Yamamoto K, Ohno H. Chemical Synthesis and Evaluation of Exopolysaccharide Fragments Produced by Leuconostoc mesenteroides Strain NTM048. Chem Pharm Bull (Tokyo) 2022; 70:155-161. [PMID: 35110436 DOI: 10.1248/cpb.c21-00919] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Exopolysaccharides (EPSs) occur widely in natural products made by bacteria, fungi and algae. Some EPSs have intriguing biological properties such as anticancer and immunomodulatory activities. Our group has recently found that EPSs generated from Leuconostoc mesenteroides ssp. mesenteroides strain NTM048 (NTM048 EPS) enhanced a production of mucosal immunoglobulin A (IgA) of mouse. Herein, we described the synthesis and evaluation of the tetrasaccharide fragments of NTM048 EPS to obtain information about the molecular mechanism responsible for the IgA-inducing activity.
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Affiliation(s)
- Shinsuke Inuki
- Graduate School of Pharmaceutical Sciences, Kyoto University
| | - Hitomi Tabuchi
- Graduate School of Pharmaceutical Sciences, Kyoto University
| | - Chiaki Matsuzaki
- Research Institute for Bioresources and Biotechnology, Ishikawa Prefectural University
| | | | | | - Ikuo Kimura
- Graduate School of Biostudies, Kyoto University.,AMED-CREST, Japan Agency for Medical Research and Development
| | - Kenji Yamamoto
- Research Institute for Bioresources and Biotechnology, Ishikawa Prefectural University
| | - Hiroaki Ohno
- Graduate School of Pharmaceutical Sciences, Kyoto University
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9
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Li J, Nguyen HM. A Mechanistic Probe into 1,2- cis Glycoside Formation Catalyzed by Phenanthroline and Further Expansion of Scope. Adv Synth Catal 2021; 363:4054-4066. [PMID: 35431716 PMCID: PMC9009828 DOI: 10.1002/adsc.202100639] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Indexed: 12/20/2022]
Abstract
Phenanthroline, a rigid and planar compound with two fused pyridine rings, has been used as a powerful ligand for metals and a binding agent for DNA/RNA. We discovered that phenanthroline could be used as a nucleophilic catalyst to efficiently access high yielding and diastereoselective α-1,2-cis glycosides through the coupling of hydroxyl acceptors with α-glycosyl bromide donors. We have conducted an extensive investigation into the reaction mechanism, wherein the two glycosyl phenanthrolinium ion intermediates, a 4C1 chair-liked β-conformer and a B2,5 boat-like α-conformer, have been detected in a ratio of 2:1 (β:α) using variable temperature NMR experiments. Furthermore, NMR studies illustrate that a hydrogen bonding is formed between the second nitrogen atom of phenanthroline and the C1-anomeric hydrogen of sugar moiety to stabilize the phenanthrolinium ion intermediates. To obtain high α-1,2-cis stereoselectivity, a Curtin-Hammett scenario was proposed wherein interconversion of the 4C1 chair-like β-conformer and B2,5 boat-like α-conformer is more rapid than nucleophilic addition. Hydroxyl attack takes place from the α-face of the more reactive 4C1 β-phenanthrolinium intermediate to give an α-anomeric product. The utility of the phenanthroline catalysis is expanded to sterically hindered hydroxyl nucleophiles and chemoselective coupling of an alkyl hydroxyl group in the presence of a free C1-hemiacetal. In addition, the phenanthroline-based catalyst has a pronounced effect on site-selective couplings of triol motifs and orthogonally activates the anomeric bromide leaving group over the anomeric fluoride and sulfide counterparts.
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Affiliation(s)
- Jiayi Li
- 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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10
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Zhang Y, He H, Chen Z, Huang Y, Xiang G, Li P, Yang X, Lu G, Xiao G. Merging Reagent Modulation and Remote Anchimeric Assistance for Glycosylation: Highly Stereoselective Synthesis of α‐Glycans up to a 30‐mer. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202103826] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- Yunqin Zhang
- State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of Botany University of Chinese Academy of Sciences Chinese Academy of Sciences 132 Lanhei Road Kunming 650201 China
| | - Haiqing He
- State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of Botany University of Chinese Academy of Sciences Chinese Academy of Sciences 132 Lanhei Road Kunming 650201 China
| | - Zixi Chen
- State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of Botany University of Chinese Academy of Sciences Chinese Academy of Sciences 132 Lanhei Road Kunming 650201 China
| | - Yingying Huang
- State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of Botany University of Chinese Academy of Sciences Chinese Academy of Sciences 132 Lanhei Road Kunming 650201 China
| | - Guisheng Xiang
- State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of Botany University of Chinese Academy of Sciences Chinese Academy of Sciences 132 Lanhei Road Kunming 650201 China
| | - Penghua Li
- State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of Botany University of Chinese Academy of Sciences Chinese Academy of Sciences 132 Lanhei Road Kunming 650201 China
| | - Xingkuan Yang
- State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of Botany University of Chinese Academy of Sciences Chinese Academy of Sciences 132 Lanhei Road Kunming 650201 China
| | - Gang Lu
- Key Laboratory of Colloid and Interface Chemistry Ministry of Education School of Chemistry and Chemical Engineering State Key Laboratory of Crystal Materials Shandong University Jinan Shandong 250100 China
| | - Guozhi Xiao
- State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of Botany University of Chinese Academy of Sciences Chinese Academy of Sciences 132 Lanhei Road Kunming 650201 China
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11
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Zhang Y, He H, Chen Z, Huang Y, Xiang G, Li P, Yang X, Lu G, Xiao G. Merging Reagent Modulation and Remote Anchimeric Assistance for Glycosylation: Highly Stereoselective Synthesis of α-Glycans up to a 30-mer. Angew Chem Int Ed Engl 2021; 60:12597-12606. [PMID: 33763930 DOI: 10.1002/anie.202103826] [Citation(s) in RCA: 39] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2021] [Indexed: 12/12/2022]
Abstract
The efficient synthesis of long, branched, and complex carbohydrates containing multiple 1,2-cis glycosidic linkages is a long-standing challenge. Here, we report a merging reagent modulation and 6-O-levulinoyl remote anchimeric assistance glycosylation strategy, which is successfully applied to the first highly stereoselective synthesis of the branched Dendrobium Huoshanense glycans and the linear Longan glycans containing up to 30 contiguous 1,2-cis glucosidic bonds. DFT calculations shed light on the origin of the much higher stereoselectivities of 1,2-cis glucosylation with 6-O-levulinoyl group than 6-O-acetyl or 6-O-benzoyl groups. Orthogonal one-pot glycosylation strategy based on glycosyl ortho-alkynylbenzoates and ortho-(1-phenylvinyl)benzoates has been demonstrated in the efficient synthesis of complex glycans, precluding such issues as aglycon transfer inherent to orthogonal one-pot synthesis based on thioglycosides.
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Affiliation(s)
- Yunqin Zhang
- State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 132 Lanhei Road, Kunming, 650201, China
| | - Haiqing He
- State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 132 Lanhei Road, Kunming, 650201, China
| | - Zixi Chen
- State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 132 Lanhei Road, Kunming, 650201, China
| | - Yingying Huang
- State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 132 Lanhei Road, Kunming, 650201, China
| | - Guisheng Xiang
- State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 132 Lanhei Road, Kunming, 650201, China
| | - Penghua Li
- State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 132 Lanhei Road, Kunming, 650201, China
| | - Xingkuan Yang
- State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 132 Lanhei Road, Kunming, 650201, China
| | - Gang Lu
- Key Laboratory of Colloid and Interface Chemistry, Ministry of Education, School of Chemistry and Chemical Engineering, State Key Laboratory of Crystal Materials, Shandong University, Jinan, Shandong, 250100, China
| | - Guozhi Xiao
- State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 132 Lanhei Road, Kunming, 650201, China
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12
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Tokatly AI, Vinnitskiy DZ, Ustuzhanina NE, Nifantiev NE. Protecting Groups as a Factor of Stereocontrol in Glycosylation Reactions. RUSSIAN JOURNAL OF BIOORGANIC CHEMISTRY 2021. [DOI: 10.1134/s1068162021010258] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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13
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Cai L, Meng L, Zeng J, Wan Q. Sequential activation of thioglycosides enables one-pot glycosylation. Org Chem Front 2021. [DOI: 10.1039/d0qo01414a] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
This review describes recent developments in relative reactivity value (RRV) controlled sequential glycosylation, pre-activation based iterative glycosylation, and sulfoxide activation initiated one-pot glycosylation.
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Affiliation(s)
- Lei Cai
- Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation
- School of Pharmacy
- Huazhong University of Science and Technology
- Wuhan
- China
| | - Lingkui Meng
- Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation
- School of Pharmacy
- Huazhong University of Science and Technology
- Wuhan
- China
| | - Jing Zeng
- Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation
- School of Pharmacy
- Huazhong University of Science and Technology
- Wuhan
- China
| | - Qian Wan
- Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation
- School of Pharmacy
- Huazhong University of Science and Technology
- Wuhan
- China
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14
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Tang Y, Reddy DP, Yu B. A dehydrative glycosylation protocol mediated by nonafluorobutanesulfonyl fluoride (NfF). Tetrahedron 2021. [DOI: 10.1016/j.tet.2020.131800] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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15
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Shadrick M, Singh Y, Demchenko AV. Stereocontrolled α-Galactosylation under Cooperative Catalysis. J Org Chem 2020; 85:15936-15944. [PMID: 33064474 PMCID: PMC8142852 DOI: 10.1021/acs.joc.0c01279] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
A recent discovery of a cooperative catalysis comprising a silver salt and an acid led to a dramatic improvement in the way glycosyl halides are glycosidated. Excellent yields have been achieved, but the stereoselectivity achieved with 2-O-benzylated donors was poor. Reported herein is our first attempt to refine the stereoselectivity of the cooperatively catalyzed galactosylation reaction. Careful optimization of the reaction conditions along with studying effects of the remote protecting groups led to excellent stereocontrol of α-galactosylation of a variety of glycosyl acceptors with differentially protected galactosyl donors.
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Affiliation(s)
- Melanie Shadrick
- Department of Chemistry and Biochemistry, University of Missouri—St. Louis, St. Louis, Missouri 63121, United States
| | - Yashapal Singh
- Department of Chemistry and Biochemistry, University of Missouri—St. Louis, St. Louis, Missouri 63121, United States
| | - Alexei V. Demchenko
- Department of Chemistry and Biochemistry, University of Missouri—St. Louis, St. Louis, Missouri 63121, United States
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16
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Yu F, Dickson JL, Loka RS, Xu H, Schaugaard RN, Schlegel HB, Luo L, Nguyen HM. Diastereoselective sp 3 C-O Bond Formation via Visible Light-Induced, Copper-Catalyzed Cross-Couplings of Glycosyl Bromides with Aliphatic Alcohols. ACS Catal 2020; 10:5990-6001. [PMID: 34168901 DOI: 10.1021/acscatal.0c01470] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Copper-catalyzed cross-coupling reactions have become one of the most powerful methods for generating carbon-heteroatom bonds, an important framework of many organic molecules. However, copper-catalyzed C(sp3)-O cross-coupling of alkyl halides with alkyl alcohols remains elusive because of the sluggish nature of oxidative addition to copper. To address this challenge, we have developed a catalytic copper system, which overcomes the copper oxidative addition barrier with the aid of visible light and effectively facilitates the cross-couplings of glycosyl bromides with aliphatic alcohols to afford C(sp3)-O bonds with high levels of diastereoselectivity. Importantly, this catalytic system leads to a mild and efficient method for stereoselective construction of α-1,2-cis glycosides, which are of paramount importance, but challenging. In general, stereochemical outcomes in α-1,2-cis glycosidic C-O bond-forming processes are unpredictable and dependent on the steric and electronic nature of protecting groups bound to carbohydrate coupling partners. Currently, the most reliable approaches rely on the use of a chiral auxiliary or hydrogen-bond directing group at the C2- and C4-position of carbohydrate electrophiles to control α-1,2-cis selectivity. In our approach, earth-abundant copper not only acts as a photocatalyst and a bond-forming catalyst, but also enforces the stereocontrolled formation of anomeric C-O bonds. This cross-coupling protocol enables highly diastereoselective access to a wide variety of α-1,2-cis-glycosides and biologically relevant α-glycan oligosaccharides. Our work provides a foundation for developing new methods for the stereoselective construction of natural and unnatural anomeric carbon(sp3)-heteroatom bonds.
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Affiliation(s)
- Fei Yu
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202, United States
| | - Jalen L. Dickson
- Department of Chemistry, University of Iowa, Iowa City, Iowa 52242, United States
| | - Ravi S. Loka
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202, United States
| | - Hengfu Xu
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202, United States
| | - Richard N. Schaugaard
- 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
| | - Long Luo
- 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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17
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Zhang Y, Zhang H, Zhao Y, Guo Z, Gao J. Efficient Strategy for α-Selective Glycosidation of d-Glucosamine and Its Application to the Synthesis of a Bacterial Capsular Polysaccharide Repeating Unit Containing Multiple α-Linked GlcNAc Residues. Org Lett 2020; 22:1520-1524. [DOI: 10.1021/acs.orglett.0c00101] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- Yanxin Zhang
- National Glycoengineering Research Center, Shandong Key Laboratory of Carbohydrate Chemistry and Glycobiology, Shandong University, Qingdao, Shandong 266237, China
| | - Han Zhang
- National Glycoengineering Research Center, Shandong Key Laboratory of Carbohydrate Chemistry and Glycobiology, Shandong University, Qingdao, Shandong 266237, China
| | - Ying Zhao
- National Glycoengineering Research Center, Shandong Key Laboratory of Carbohydrate Chemistry and Glycobiology, Shandong University, Qingdao, Shandong 266237, China
| | - Zhongwu Guo
- Department of Chemistry, University of Florida, 214 Leigh Hall, Gainesville, Florida 32611, United States
| | - Jian Gao
- National Glycoengineering Research Center, Shandong Key Laboratory of Carbohydrate Chemistry and Glycobiology, Shandong University, Qingdao, Shandong 266237, China
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18
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Zhao Q, Zhang H, Zhang Y, Zhou S, Gao J. Stereoselective synthesis of a branched α-decaglucan. Org Biomol Chem 2020; 18:6549-6557. [PMID: 32789329 DOI: 10.1039/d0ob01402h] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The first and convergent synthesis of a branched Arca subcrenata Lischke α-decaglucan containing all of the α-(1 → 3), α-(1 → 4), and α-(1 → 6) glycosyl linkages was efficiently achieved. The tri- and tetrasaccharide fragments and fully protected decasaccharide were assembled in a one-pot manner with excellent α-stereoselectivity, which was secured by the synergistic α-directing effects of the TolSCl/AgOTf catalysis system and the remote participation effect or steric β-shielding of functionalized groups at the donor 6-O-position. Low substrate concentration was revealed to favor the α-stereochemical outcome of glycosylations between bulkier building blocks. The synthetic approach established here would be very useful for the preparation of more complex α-glucans containing different types of glycosidic linkages and branched architectures.
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Affiliation(s)
- Qingpeng Zhao
- National Glycoengineering Research Center, Shandong Key Laboratory of Carbohydrate Chemistry and Glycobiology, Shandong University, Qingdao, Shandong 266237, China.
| | - Han Zhang
- National Glycoengineering Research Center, Shandong Key Laboratory of Carbohydrate Chemistry and Glycobiology, Shandong University, Qingdao, Shandong 266237, China.
| | - Yanxin Zhang
- National Glycoengineering Research Center, Shandong Key Laboratory of Carbohydrate Chemistry and Glycobiology, Shandong University, Qingdao, Shandong 266237, China.
| | - Shihao Zhou
- National Glycoengineering Research Center, Shandong Key Laboratory of Carbohydrate Chemistry and Glycobiology, Shandong University, Qingdao, Shandong 266237, China.
| | - Jian Gao
- National Glycoengineering Research Center, Shandong Key Laboratory of Carbohydrate Chemistry and Glycobiology, Shandong University, Qingdao, Shandong 266237, China.
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19
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Hamala V, Červenková Šťastná L, Kurfiřt M, Cuřínová P, Dračínský M, Karban J. Use of remote acyl groups for stereoselective 1,2-cis-glycosylation with fluorinated glucosazide thiodonors. Org Biomol Chem 2020; 18:5427-5434. [DOI: 10.1039/d0ob01065k] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Introducing remote O-acyl protecting groups enabled 1,2-cis stereoselective glycosylation with fluorinated glucosazide glycosyl donors.
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Affiliation(s)
- Vojtěch Hamala
- Institute of Chemical Process Fundamentals of the CAS
- 16502 Praha 6
- Czech Republic
- University of Chemistry and Technology Prague
- 16628 Praha 6
| | | | - Martin Kurfiřt
- Institute of Chemical Process Fundamentals of the CAS
- 16502 Praha 6
- Czech Republic
- University of Chemistry and Technology Prague
- 16628 Praha 6
| | - Petra Cuřínová
- Institute of Chemical Process Fundamentals of the CAS
- 16502 Praha 6
- Czech Republic
| | - Martin Dračínský
- Institute of Organic Chemistry and Biochemistry of the CAS
- Praha 6
- Czech Republic
| | - Jindřich Karban
- Institute of Chemical Process Fundamentals of the CAS
- 16502 Praha 6
- Czech Republic
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20
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Underlin EN, Böhm M, Madsen R. Synthesis of Arabinoxylan Oligosaccharides by Preactivation-Based Iterative Glycosylations. J Org Chem 2019; 84:16036-16054. [PMID: 31762276 DOI: 10.1021/acs.joc.9b02529] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
A concise synthetic strategy has been developed for assembling densely substituted arabinoxylan oligosaccharides, which are valuable substrates for characterizing hemicellulose-degrading enzymes. The xylan backbone has been prepared by an iterative preactivation-based glycosylation approach with phenyl thioglycosides. The preactivation has been performed with in situ generated p-nitrobenzenesulfenyl triflate prior to addition of the acceptor. The glycosylation temperature was shown to have an important impact on the yield of the coupling. The arabinose substituents have been introduced in one high-yielding glycosylation with an N-phenyl trifluoroacetimidate donor. The strategy has been successfully employed for the synthesis of three heptasaccharides in seven steps and overall yields of 24-36% from the corresponding monosaccharide building blocks.
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Affiliation(s)
- Emilie N Underlin
- Department of Chemistry , Technical University of Denmark , 2800 Kgs. Lyngby , Denmark
| | - Maximilian Böhm
- Department of Chemistry , Technical University of Denmark , 2800 Kgs. Lyngby , Denmark
| | - Robert Madsen
- Department of Chemistry , Technical University of Denmark , 2800 Kgs. Lyngby , Denmark
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21
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Cai L, Zeng J, Li T, Xiao Y, Ma X, Xiao X, Zhang Q, Meng L, Wan Q. Dehydrative Glycosylation Enabled by a Comproportionation Reaction of 2‐Aryl‐1,3‐dithiane 1‐Oxide
†. CHINESE J CHEM 2019. [DOI: 10.1002/cjoc.201900419] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Lei Cai
- Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of PharmacyHuazhong University of Science and Technology, 13 Hangkong Road Wuhan Hubei 430030 China
| | - Jing Zeng
- Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of PharmacyHuazhong University of Science and Technology, 13 Hangkong Road Wuhan Hubei 430030 China
| | - Ting Li
- Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of PharmacyHuazhong University of Science and Technology, 13 Hangkong Road Wuhan Hubei 430030 China
| | - Ying Xiao
- Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of PharmacyHuazhong University of Science and Technology, 13 Hangkong Road Wuhan Hubei 430030 China
| | - Xiang Ma
- Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of PharmacyHuazhong University of Science and Technology, 13 Hangkong Road Wuhan Hubei 430030 China
| | - Xiong Xiao
- Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of PharmacyHuazhong University of Science and Technology, 13 Hangkong Road Wuhan Hubei 430030 China
| | - Qin Zhang
- Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of PharmacyHuazhong University of Science and Technology, 13 Hangkong Road Wuhan Hubei 430030 China
| | - Lingkui Meng
- Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of PharmacyHuazhong University of Science and Technology, 13 Hangkong Road Wuhan Hubei 430030 China
| | - Qian Wan
- Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of PharmacyHuazhong University of Science and Technology, 13 Hangkong Road Wuhan Hubei 430030 China
- Institute of Brain Research, Huazhong University of Science and Technology, 13 Hangkong Road Wuhan Hubei 430030 China
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22
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Zhang H, Shao L, Wang X, Zhang Y, Guo Z, Gao J. One-Pot Synthesis of the Repeating Unit of Type VII Group B Streptococcus Polysaccharide and the Dimer. Org Lett 2019; 21:2374-2377. [DOI: 10.1021/acs.orglett.9b00653] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- Han Zhang
- National Glycoengineering Research Center, Shandong Provincial Key Laboratory of Carbohydrate Chemistry and Glycobiology, Shandong University, Qingdao, Shandong 266237, China
| | - Liming Shao
- National Glycoengineering Research Center, Shandong Provincial Key Laboratory of Carbohydrate Chemistry and Glycobiology, Shandong University, Qingdao, Shandong 266237, China
| | - Xiaohan Wang
- National Glycoengineering Research Center, Shandong Provincial Key Laboratory of Carbohydrate Chemistry and Glycobiology, Shandong University, Qingdao, Shandong 266237, China
| | - Yanxin Zhang
- National Glycoengineering Research Center, Shandong Provincial Key Laboratory of Carbohydrate Chemistry and Glycobiology, Shandong University, Qingdao, Shandong 266237, China
| | - Zhongwu Guo
- National Glycoengineering Research Center, Shandong Provincial Key Laboratory of Carbohydrate Chemistry and Glycobiology, Shandong University, Qingdao, Shandong 266237, China
- Department of Chemistry, University of Florida, 214 Leigh Hall, Gainesville, Florida 32611, United States
| | - Jian Gao
- National Glycoengineering Research Center, Shandong Provincial Key Laboratory of Carbohydrate Chemistry and Glycobiology, Shandong University, Qingdao, Shandong 266237, China
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