1
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Yu C, Xu Y, Zeng M, Wang J, Dai W, Wang J, Liu H. Direct Construction of C-Alkyl Glycosides from Non-Activated Olefins via Nickel-Catalyzed C(sp 3)─C(sp 3) Coupling Reaction. Adv Sci (Weinh) 2024; 11:e2307226. [PMID: 38235616 DOI: 10.1002/advs.202307226] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2023] [Revised: 12/05/2023] [Indexed: 01/19/2024]
Abstract
Among C-glycosides, C-alkyl glycosides are significant building blocks for natural products and glycopeptides. However, research on efficient construction methods for C-alkyl glycosides remains relatively limited. Compared with Michael acceptors, non-activated olefins are more challenging substrates and have rarely been employed in the construction of C-glycosides. Here, a highly efficient and convenient approach for the synthesis of C-alkyl glycosides through a nickel-catalyzed C(sp3)-C(sp3) coupling reaction is presented. A distinctive feature of this method is its utilization of non-activated olefins as the anomeric radical acceptors for hydroalkylation, allowing for the direct formation of C-glycoside bonds in a single step. Furthermore, this method demonstrates excellent compatibility with a broad scope of highly reactive functional groups. Mechanistic investigations suggest that the reaction proceeds via a free radical pathway, leading predominantly to the formation of products with α-configuration. Overall, this innovative methodology offers a versatile and practical approach for the synthesis of C-alkyl glycosides, offering new avenues for the production of intricate glycosides with potential applications in drug discovery and chemical biology.
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Affiliation(s)
- Changyue Yu
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, 201203, China
- School of Pharmacy, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Yinghuan Xu
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, 201203, China
- School of Pharmacy, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Mingjie Zeng
- School of Pharmacy, China Pharmaceutical University, Nanjing, 211198, China
| | - Jingjing Wang
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, 201203, China
- School of Pharmacy, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Wenhao Dai
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, 201203, China
- School of Pharmacy, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Jiang Wang
- Lingang Laboratory, Shanghai, 200031, China
| | - Hong Liu
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, 201203, China
- School of Pharmacy, University of Chinese Academy of Sciences, Beijing, 100049, China
- School of Pharmacy, China Pharmaceutical University, Nanjing, 211198, China
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2
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Hu LY, Zhang SY, Zhu L, Li Y, Luo K, Wu L. "Boomerang" Strategy in Carbohydrate Chemistry: Diastereoselective Synthesis of C-Glycosylated Benzothiazoles from ortho-Isocyanophenyl Thioglycosides. Org Lett 2024; 26:215-220. [PMID: 38117978 DOI: 10.1021/acs.orglett.3c03817] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2023]
Abstract
This paper reveals a novel "boomerang" strategy in the expedient and diastereoselective synthesis of C-nucleoside analogues. Bench-stable ortho-isocyanophenyl thioglycosides can be converted to glycosyl radicals through rapid and efficient C-S bond homolysis when they are irradiated by visible light. The glycosyl radicals are subsequently trapped by the corresponding leaving group or other radical acceptors to provide diverse C-nucleoside analogues under mild conditions.
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Affiliation(s)
- Li-Yan Hu
- Jiangsu Key Laboratory of Pesticide Science and Department of Chemistry, College of Sciences, Nanjing Agricultural University, Nanjing 210095, P. R. China
| | - Shen-Yuan Zhang
- Jiangsu Key Laboratory of Pesticide Science and Department of Chemistry, College of Sciences, Nanjing Agricultural University, Nanjing 210095, P. R. China
| | - Li Zhu
- Jiangsu Key Laboratory of Pesticide Science and Department of Chemistry, College of Sciences, Nanjing Agricultural University, Nanjing 210095, P. R. China
| | - Yang Li
- Jiangsu Key Laboratory of Pesticide Science and Department of Chemistry, College of Sciences, Nanjing Agricultural University, Nanjing 210095, P. R. China
| | - Kai Luo
- Jiangsu Key Laboratory of Pesticide Science and Department of Chemistry, College of Sciences, Nanjing Agricultural University, Nanjing 210095, P. R. China
| | - Lei Wu
- Jiangsu Key Laboratory of Pesticide Science and Department of Chemistry, College of Sciences, Nanjing Agricultural University, Nanjing 210095, P. R. China
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3
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Khanam A, Dubey S, Mandal PK. Mild method for the synthesis of α-glycosyl chlorides: A convenient protocol for quick one-pot glycosylation. Carbohydr Res 2023; 534:108976. [PMID: 37871478 DOI: 10.1016/j.carres.2023.108976] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2023] [Revised: 10/17/2023] [Accepted: 10/18/2023] [Indexed: 10/25/2023]
Abstract
A simple and efficient protocol for the preparation of α-glycosyl chlorides within 15-30 min is described which employs a stable, cheap, and commercially available Trichloroisocyanuric acid (TCCA) as non-toxic chlorinating agent along with PPh3. This process involved a wide range of substrate scope and is well-suited with labile hydroxyl protecting groups such as benzyl, acetyl, benzoyl, isopropylidene, benzylidene, and TBDPS (tert-butyldiphenylsilyl) groups. This process is operationally simple, mild conditions and obtained good yields with excellent α selectivity. Moreover, a multi-catalyst one-pot glycosylation can be carried out to transform the glycosyl hemiacetals directly to a various O-glycosides in high overall yields without the need for separation or purification of the α-glycosyl chloride donors.
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Affiliation(s)
- Ariza Khanam
- Medicinal and Process Chemistry Division, CSIR-Central Drug Research Institute, BS-10/1, Sector 10, Jankipuram Extension, Sitapur Road, P.O. Box 173, Lucknow, 226 031, India
| | - Shashiprabha Dubey
- Medicinal and Process Chemistry Division, CSIR-Central Drug Research Institute, BS-10/1, Sector 10, Jankipuram Extension, Sitapur Road, P.O. Box 173, Lucknow, 226 031, India
| | - Pintu Kumar Mandal
- Medicinal and Process Chemistry Division, CSIR-Central Drug Research Institute, BS-10/1, Sector 10, Jankipuram Extension, Sitapur Road, P.O. Box 173, Lucknow, 226 031, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India.
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4
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Singh K, Sharma S, Tyagi R, Sagar R. Recent progress in the synthesis of natural product inspired bioactive glycohybrids. Carbohydr Res 2023; 534:108975. [PMID: 37871479 DOI: 10.1016/j.carres.2023.108975] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2023] [Revised: 10/06/2023] [Accepted: 10/10/2023] [Indexed: 10/25/2023]
Abstract
Carbohydrates are a basic structural component that are indispensable to all cellular processes. In addition to being employed as chiral starting materials in the synthesis of a variety of natural products, carbohydrates are recognized as naturally occurring molecules having an enormous variety of functional, stereochemical, and structural properties. The understanding and biological roles of carbohydrate derived molecules can be greatly improved by selectively synthesizing functional carbohydrates through incorporating them with privileged scaffolds. For a deeper understanding of their roles and the development of functional materials based on sugar, it is crucial to develop new techniques for efficiently synthesizing, functionalizing, and modifying carbohydrates. Glycohybrids have a wide range of structural and functional characteristics along with protein-carbohydrate interactions that are crucial to mammalian biology and a number of disease states. This review, consisting the literature from January 2017 to July 2023 and provide an overview of recent developments in the chemical synthesis of glycohybrids based on natural product scaffolds of coumarin, quinolone, naphthalene diimide, indole, isatin, naphthoquinone, imidazole and pyrimidine. The biological activity of active glycohybrids are discussed in this review.
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Affiliation(s)
- Kavita Singh
- Glycochemistry Laboratory, School of Physical Sciences, Jawaharlal Nehru University, New Delhi, 110067, India
| | - Sunil Sharma
- Glycochemistry Laboratory, School of Physical Sciences, Jawaharlal Nehru University, New Delhi, 110067, India
| | - Rajdeep Tyagi
- Glycochemistry Laboratory, School of Physical Sciences, Jawaharlal Nehru University, New Delhi, 110067, India
| | - Ram Sagar
- Glycochemistry Laboratory, School of Physical Sciences, Jawaharlal Nehru University, New Delhi, 110067, India.
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5
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Xiao X, Han P, Wan JP, Liu J. Stereoselective Synthesis of Indolyl- C-glycosides Enabled by Sequential Aminopalladation and Heck Glycosylation of 2-Alkynylanilines with Glycals. Org Lett 2023; 25:7170-7175. [PMID: 37756216 DOI: 10.1021/acs.orglett.3c02688] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/29/2023]
Abstract
An efficient and general approach for the synthesis of indolyl-C-glycosides via aminopalladation and subsequent Heck-type glycosylation of easily available 2-alkynylanilines and glycals has been developed. This protocol features excellent stereoselectivity, a broad substrate scope, and mild reaction conditions. In addition, 2,3-pseudoglycals also successfully participated in this cascade reaction, affording C2/C3-branched indolyl glycosides with high regio-/stereoselectivity. The utility of this protocol was also demonstrated by a large-scale reaction and diversified synthetic transformations of the desired products.
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Affiliation(s)
- Xiao Xiao
- National Engineering Research Center for Carbohydrate Synthesis, College of Chemistry and Chemical Engineering, Jiangxi Normal University, Nanchang, Jiangxi 330022, P. R. China
| | - Puren Han
- National Engineering Research Center for Carbohydrate Synthesis, College of Chemistry and Chemical Engineering, Jiangxi Normal University, Nanchang, Jiangxi 330022, P. R. China
| | - Jie-Ping Wan
- National Engineering Research Center for Carbohydrate Synthesis, College of Chemistry and Chemical Engineering, Jiangxi Normal University, Nanchang, Jiangxi 330022, P. R. China
| | - Jianchao Liu
- National Engineering Research Center for Carbohydrate Synthesis, College of Chemistry and Chemical Engineering, Jiangxi Normal University, Nanchang, Jiangxi 330022, P. R. China
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6
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Mu QQ, Guo AX, Cai X, Qin YY, Liu XL, Ye FZ, Yang HJ, Xiao X, Liu XW. Cobalt's Dual Role in Promoting C3-Glycosylation of Indoles: Unraveling Mechanistic Insights. Org Lett 2023; 25:7040-7045. [PMID: 37721454 DOI: 10.1021/acs.orglett.3c02624] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/19/2023]
Abstract
In this study, we present a cobalt-catalyzed C3-glycosylation of indoles using unfunctionalized glycals, yielding 3-indolyl-C-deoxyglycosides. These compounds hold promise as sodium-dependent glucose cotransporter 2 (SGLT2) inhibitors for treating type 2 diabetes. Control experiments unveiled that cobalt assumes a dual role, facilitating catalytic C-glycosylation while unexpectedly driving the anomerization of α-anomers through endocyclic cleavage of the C1-O5 bond, resulting in the formation of β-C-deoxyglycosides. Furthermore, density functional theory (DFT) calculations shed light on the reaction mechanism, emphasizing the significant role of the pyridine group of indole in stabilizing transition states and intermediates.
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Affiliation(s)
- Qiu-Qi Mu
- School of Chemistry and Chemical Engineering, Northwestern Polytechnical University, Xi'an, Shaanxi 710072, P. R. China
| | - Ao-Xin Guo
- School of Chemistry, Chemical Engineering and Biotechnology Nanyang Technological University, 21 Nanyang Link, Singapore, 637371, Singapore
| | - Xin Cai
- School of Chemistry and Chemical Engineering, Northwestern Polytechnical University, Xi'an, Shaanxi 710072, P. R. China
| | - Yang-Yang Qin
- School of Chemistry and Chemical Engineering, Northwestern Polytechnical University, Xi'an, Shaanxi 710072, P. R. China
| | - Xing-Le Liu
- School of Chemistry and Chemical Engineering, Northwestern Polytechnical University, Xi'an, Shaanxi 710072, P. R. China
| | - Fang-Zhen Ye
- School of Chemistry and Chemical Engineering, Northwestern Polytechnical University, Xi'an, Shaanxi 710072, P. R. China
| | - Hui-Jie Yang
- School of Chemistry and Chemical Engineering, Northwestern Polytechnical University, Xi'an, Shaanxi 710072, P. R. China
| | - Xiong Xiao
- School of Chemistry and Chemical Engineering, Northwestern Polytechnical University, Xi'an, Shaanxi 710072, P. R. China
| | - Xue-Wei Liu
- School of Chemistry, Chemical Engineering and Biotechnology Nanyang Technological University, 21 Nanyang Link, Singapore, 637371, Singapore
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7
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Dörrenhaus R, Wagner PK, Kath-Schorr S. Two are not enough: synthetic strategies and applications of unnatural base pairs. Biol Chem 2023; 404:883-896. [PMID: 37354104 DOI: 10.1515/hsz-2023-0169] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Accepted: 06/05/2023] [Indexed: 06/26/2023]
Abstract
Nucleic acid chemistry is a rapidly evolving field, and the need for novel nucleotide modifications and artificial nucleotide building blocks for diagnostic and therapeutic use, material science or for studying cellular processes continues unabated. This review focusses on the development and application of unnatural base pairs as part of an expanded genetic alphabet. Not only recent developments in "nature-like" artificial base pairs are presented, but also current synthetic methods to get access to C-glycosidic nucleotides. Wide-ranging viability in synthesis is a prerequisite for the successful use of unnatural base pairs in a broader spectrum and will be discussed.
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8
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Xia Y, Wang Y, Zhang Z, Gulzar T, Lin Y, Wang J, Zhu D, Yu B. Synthesis of 2-Indolyl C-Glycoside Neopetrosins A and C and Congeners via Ni-Catalyzed Photoreductive Cross-Coupling. Org Lett 2023; 25:6741-6745. [PMID: 37646796 DOI: 10.1021/acs.orglett.3c02601] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/01/2023]
Abstract
The synthesis of neopetrosins A and C, two 2-indolyl C-α-d-mannopyranosides, and their congeners has been realized via a direct Ni/photoredox-catalyzed reductive coupling of 3-methoxycarbonyl-2-iodo-1H-indoles with pyranosyl bromides.
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Affiliation(s)
- Yan Xia
- State Key Laboratory of Chemical Biology, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai 200032, China
| | - Yingjie Wang
- State Key Laboratory of Chemical Biology, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai 200032, China
| | - Zhaolun Zhang
- State Key Laboratory of Chemical Biology, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai 200032, China
| | - Tayyab Gulzar
- State Key Laboratory of Chemical Biology, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai 200032, China
| | - Yuqi Lin
- State Key Laboratory of Chemical Biology, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai 200032, China
| | - Jing Wang
- State Key Laboratory of Chemical Biology, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai 200032, China
| | - Dapeng Zhu
- Institute of Translational Medicine, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Biao Yu
- State Key Laboratory of Chemical Biology, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai 200032, China
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9
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Parida SP, Das T, Ahemad MA, Pati T, Mohapatra S, Nayak S. Recent advances on synthesis of C-glycosides. Carbohydr Res 2023; 530:108856. [PMID: 37315353 DOI: 10.1016/j.carres.2023.108856] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Revised: 05/17/2023] [Accepted: 05/29/2023] [Indexed: 06/16/2023]
Abstract
In recent years, C-glycosides have emerged as significant building blocks for many naturally occurring alkaloids and pharmaceutically active drug molecules. Therefore, significant efforts have been devoted to the construction of structurally important C-glycosidic linkages in carbohydrate compounds. Herein, we have summarized the recent developments of diverse synthesis of C-glycoside core between the time period from 2019 to 2022 focusing on different catalytic strategies, such as (i) transition-metal, and (ii) metal-free catalytic approaches. Further, the transition metal catalyzed C-glycosylations have been categorized into four sub classes: (a) metal based C-H activation, (b) cross-coupling reaction, (c) glycosyl radical intermediate-based process, and (d) Others.
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Affiliation(s)
| | - Tapaswini Das
- Department of Chemistry, Ravenshaw University, Cuttack, 753003, India
| | | | - Tapaswini Pati
- Department of Chemistry, Ravenshaw University, Cuttack, 753003, India
| | | | - Sabita Nayak
- Department of Chemistry, Ravenshaw University, Cuttack, 753003, India.
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10
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Bloch JS, John A, Mao R, Mukherjee S, Boilevin J, Irobalieva RN, Darbre T, Scott NE, Reymond JL, Kossiakoff AA, Goddard-Borger ED, Locher KP. Structure, sequon recognition and mechanism of tryptophan C-mannosyltransferase. Nat Chem Biol 2023; 19:575-584. [PMID: 36604564 PMCID: PMC10154233 DOI: 10.1038/s41589-022-01219-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Accepted: 10/28/2022] [Indexed: 01/07/2023]
Abstract
C-linked glycosylation is essential for the trafficking, folding and function of secretory and transmembrane proteins involved in cellular communication processes. The tryptophan C-mannosyltransferase (CMT) enzymes that install the modification attach a mannose to the first tryptophan of WxxW/C sequons in nascent polypeptide chains by an unknown mechanism. Here, we report cryogenic-electron microscopy structures of Caenorhabditis elegans CMT in four key states: apo, acceptor peptide-bound, donor-substrate analog-bound and as a trapped ternary complex with both peptide and a donor-substrate mimic bound. The structures indicate how the C-mannosylation sequon is recognized by this CMT and its paralogs, and how sequon binding triggers conformational activation of the donor substrate: a process relevant to all glycosyltransferase C superfamily enzymes. Our structural data further indicate that the CMTs adopt an unprecedented electrophilic aromatic substitution mechanism to enable the C-glycosylation of proteins. These results afford opportunities for understanding human disease and therapeutic targeting of specific CMT paralogs.
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Affiliation(s)
- Joël S Bloch
- Institute of Molecular Biology and Biophysics, ETH Zürich, Zürich, Switzerland
- Laboratory of Molecular Neurobiology and Biophysics and Howard Hughes Medical Institute, The Rockefeller University, New York, NY, USA
| | - Alan John
- The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia
- Department of Medical Biology, University of Melbourne, Parkville, Victoria, Australia
| | - Runyu Mao
- The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia
- Department of Medical Biology, University of Melbourne, Parkville, Victoria, Australia
| | - Somnath Mukherjee
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, IL, USA
| | - Jérémy Boilevin
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Bern, Switzerland
| | | | - Tamis Darbre
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Bern, Switzerland
| | - Nichollas E Scott
- Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Parkville, Victoria, Australia
| | - Jean-Louis Reymond
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Bern, Switzerland
| | - Anthony A Kossiakoff
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, IL, USA
| | - Ethan D Goddard-Borger
- The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia.
- Department of Medical Biology, University of Melbourne, Parkville, Victoria, Australia.
| | - Kaspar P Locher
- Institute of Molecular Biology and Biophysics, ETH Zürich, Zürich, Switzerland.
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11
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Chauhan NS, Dubey A, Mandal PK. Palladium-Catalyzed Direct C-H Glycosylation of Free ( N-H) Indole and Tryptophan by Norbornene-Mediated Regioselective C-H Activation. Org Lett 2022; 24:7067-7071. [PMID: 36165771 DOI: 10.1021/acs.orglett.2c02537] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We describe the palladium-catalyzed direct C-H glycosylation of free N-H indole or tryptophan for the stereoselective synthesis of 2-glycosylindoles and tryptophan-C-glycosides. This reaction relies on the ortho-directing transient mediator norbornene, which underwent regioselective C-H functionalization at the indole or tryptophan ring, providing high chemoselectivity. This method offers a more straightforward, step-economical, and cost-effective route to construct C-glycosides. The gram-scale amenable building blocks can be further functionalized at C3 and N-H, displaying the robustness of present method.
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Affiliation(s)
- Neha Singh Chauhan
- Medicinal & Process Chemistry Division, CSIR-Central Drug Research Institute, BS-10/1, Sector 10, Jankipuram Extension, Sitapur Road, P.O. Box 173, Lucknow 226031, India.,Academy of Scientific and Innovative Research, Ghaziabad 201002, India
| | - Atul Dubey
- Medicinal & Process Chemistry Division, CSIR-Central Drug Research Institute, BS-10/1, Sector 10, Jankipuram Extension, Sitapur Road, P.O. Box 173, Lucknow 226031, India
| | - Pintu Kumar Mandal
- Medicinal & Process Chemistry Division, CSIR-Central Drug Research Institute, BS-10/1, Sector 10, Jankipuram Extension, Sitapur Road, P.O. Box 173, Lucknow 226031, India.,Academy of Scientific and Innovative Research, Ghaziabad 201002, India
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12
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Abstract
Metal-catalyzed C-H glycosylation reactions with glycosyl chloride donors have emerged as a useful strategy for the synthesis of C-glycosides. Previously, palladium and nickel complexes were reported to catalyze C-H glycosylation reactions using amide-linked bidentate auxiliaries. Herein, a ruthenium-catalyzed ortho C-H glycosylation reaction of arenes with various glycosyl chloride donors using a monodentate pyridine directing group is developed. Preliminary mechanistic studies indicated that two-electron oxidative addition and reductive elimination of ruthenocycle intermediate led to the glycosylation products.
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Affiliation(s)
- Shaokun Cai
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Qikai Sun
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Quanquan Wang
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Gang He
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Gong Chen
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
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