1
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Wu P, Xiao X, Zhou S, Meng L, Zeng J, Wan Q. Glycosylation of 2-(2-Propylsulfinyl)benzyl 1,2-Orthoester Glycosides Initiated by Sulfoxide Activation. Org Lett 2024; 26:6053-6058. [PMID: 38985301 DOI: 10.1021/acs.orglett.4c02210] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/11/2024]
Abstract
We have developed a highly effective glycosylation method that involves the activation of 2-(2-propylsulfinyl)benzyl 1,2-orthoester glycosides using triflic anhydride (Tf2O). Our research indicates that half of the glycosyl donor is activated through Tf2O via an interrupted Pummerer reaction mechanism, while the remaining portion is activated by triflic acid (TfOH) generated in situ. As a result, as little as 0.5 equiv of Tf2O is adequate for activating the orthoester glycoside donors. This glycosylation procedure offers several benefits, such as high efficiency, wide applicability, and the utilization of a recyclable leaving group.
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Affiliation(s)
- Pinru Wu
- School of Pharmacy, Huazhong University of Science and Technology, Wuhan, Hubei 430030, P. R. of China
| | - Xiong Xiao
- School of Chemistry and Chemical Engineering, Northwestern Polytechnical University, Xi'an, Shannxi 700072, P. R. of China
| | - Sicheng Zhou
- School of Pharmacy, Huazhong University of Science and Technology, Wuhan, Hubei 430030, P. R. of China
| | - Lingkui Meng
- School of Pharmacy, Huazhong University of Science and Technology, Wuhan, Hubei 430030, P. R. of China
| | - Jing Zeng
- School of Pharmacy, Huazhong University of Science and Technology, Wuhan, Hubei 430030, P. R. of China
| | - Qian Wan
- School of Pharmacy, Huazhong University of Science and Technology, Wuhan, Hubei 430030, P. R. of China
- School of Pharmaceutical Sciences, Wuhan University, Wuhan, Hubei 430071, P. R. of China
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2
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Yang J, Wei S, Zhao J, Zeng W, Shao H, Ma X. An environmentally benign protocol for the synthesis of sugar 1,2-orthoesters in poly(ethylene glycol) dimethyl ether (DMPE). Carbohydr Res 2023; 534:108902. [PMID: 38006705 DOI: 10.1016/j.carres.2023.108902] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2023] [Revised: 06/30/2023] [Accepted: 07/17/2023] [Indexed: 11/27/2023]
Abstract
An environmentally benign procedure has been developed for the synthesis of sugar orthoesters using anhydrous sodium acetate in poly (ethylene glycol)dimethyl ether (DMPE). Various sugar orthoesers were prepared without using volatile organic solvent and quaternary ammonium salt. The sugar orthoesters were obtained in good to excellent yields.
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Affiliation(s)
- Jian Yang
- Natural Products Research Centre, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, 610041, PR China; University of Chinese Academy of Sciences, Beijing, 100049, PR China
| | - Shanqiao Wei
- Natural Products Research Centre, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, 610041, PR China; University of Chinese Academy of Sciences, Beijing, 100049, PR China
| | - Jinzhong Zhao
- Natural Products Research Centre, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, 610041, PR China; University of Chinese Academy of Sciences, Beijing, 100049, PR China
| | - Wei Zeng
- Natural Products Research Centre, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, 610041, PR China; University of Chinese Academy of Sciences, Beijing, 100049, PR China
| | - Huawu Shao
- Natural Products Research Centre, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, 610041, PR China.
| | - Xiaofeng Ma
- Natural Products Research Centre, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, 610041, PR China; University of Chinese Academy of Sciences, Beijing, 100049, PR China.
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3
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Singh Y, Geringer SA, Demchenko AV. Synthesis and Glycosidation of Anomeric Halides: Evolution from Early Studies to Modern Methods of the 21st Century. Chem Rev 2022; 122:11701-11758. [PMID: 35675037 DOI: 10.1021/acs.chemrev.2c00029] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Advances in synthetic carbohydrate chemistry have dramatically improved access to common glycans. However, many novel methods still fail to adequately address challenges associated with chemical glycosylation and glycan synthesis. Since a challenge of glycosylation has remained, scientists have been frequently returning to the traditional glycosyl donors. This review is dedicated to glycosyl halides that have played crucial roles in shaping the field of glycosciences and continue to pave the way toward our understanding of chemical glycosylation.
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Affiliation(s)
- Yashapal Singh
- Department of Chemistry and Biochemistry, University of Missouri-St. Louis, One University Boulevard, St. Louis, Missouri 63121, United States
| | - Scott A Geringer
- Department of Chemistry and Biochemistry, University of Missouri-St. Louis, One University Boulevard, St. Louis, Missouri 63121, United States
| | - Alexei V Demchenko
- Department of Chemistry and Biochemistry, University of Missouri-St. Louis, One University Boulevard, St. Louis, Missouri 63121, United States.,Department of Chemistry, Saint Louis University, 3501 Laclede Avenue, St. Louis, Missouri 63103, United States
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4
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Li T, Li T, Zhang Y, Schmidt RR, Peng P. Preparation of Tea Aroma Precursor Glycosides: An Efficient and Sustainable Approach via Chemical Glycosidation. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2022; 70:2320-2327. [PMID: 35138835 DOI: 10.1021/acs.jafc.1c07043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Tea aroma precursor glycosides are plant-derived natural products with great economic value. However, the preparation of these glycosides remains largely overlooked in the past decades. Herein, we report a mild, efficient, and sustainable chemocatalytic procedure for the production of tea aroma precursor glycosides. During the study of the glycosidation, the catalysts were found to be decisive in the product formation favoring different reaction pathways; in addition, the influence of molecular sieves was elucidated. With regard to these findings, the serious problem of the competing orthoester formation side reaction was successfully overcome with low catalyst loading (1 mol %) and the use of 5 Å molecular sieves, leading to the preparation of a variety of tea aroma precursor β-d-glucopyranosides and β-primeverosides on a gram scale in high yields in an economical way. Taken together, the current approach features catalytic glycosidation with non-toxic and low-cost catalysts, demonstrates highly favorable greenness and sustainability, and promises industrial production of tea aroma precursor glycosides.
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Affiliation(s)
- Tianlu Li
- National Glycoengineering Research Center, Shandong Key Laboratory of Carbohydrate Chemistry and Glycobiology, NMPA Key Laboratory for Quality Research and Evaluation of Carbohydrate-Based Medicine, Shandong University, Jinan, Shandong 266237, People's Republic of China
| | - Tong Li
- National Glycoengineering Research Center, Shandong Key Laboratory of Carbohydrate Chemistry and Glycobiology, NMPA Key Laboratory for Quality Research and Evaluation of Carbohydrate-Based Medicine, Shandong University, Jinan, Shandong 266237, People's Republic of China
| | - Youqin Zhang
- National Glycoengineering Research Center, Shandong Key Laboratory of Carbohydrate Chemistry and Glycobiology, NMPA Key Laboratory for Quality Research and Evaluation of Carbohydrate-Based Medicine, Shandong University, Jinan, Shandong 266237, People's Republic of China
| | - Richard R Schmidt
- Department of Chemistry, University of Konstanz, D-78457 Konstanz, Germany
| | - Peng Peng
- National Glycoengineering Research Center, Shandong Key Laboratory of Carbohydrate Chemistry and Glycobiology, NMPA Key Laboratory for Quality Research and Evaluation of Carbohydrate-Based Medicine, Shandong University, Jinan, Shandong 266237, People's Republic of China
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5
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Ionescu C, Huseynova F, Barragan-Montero V. Pathways in the synthesis of functionalized glycolipids for liposomal preparations. Chem Phys Lipids 2021; 242:105161. [PMID: 34818525 DOI: 10.1016/j.chemphyslip.2021.105161] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2021] [Revised: 11/10/2021] [Accepted: 11/11/2021] [Indexed: 11/18/2022]
Abstract
We describe in this paper the synthesis of two glycolipids containing a mannosyl residue functionalized with malonic acid and azide groups at the C6 position. Two synthetic routes have been successfully implemented: the first one involves Schmidt's glycosylation procedure using functionalized carbohydrates, whereas the second one involves nucleophilic substitutions in the C6 position of an iodinated intermediate obtained using Koenigs-Knorr reaction. A comparative discussion of reactions and yields is realized. The two glycolipids served as material for the preparation of liposomes.
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Affiliation(s)
- Cătălina Ionescu
- University of Craiova, Faculty of Sciences, Department of Chemistry, 107i Calea București, 200144 Craiova, Romania.
| | - Fidan Huseynova
- LBN, University of Montpellier, Montpellier, France; Institute of Molecular Biology and Biotechnologies ANAS, Baku, Azerbaijan
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6
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Bachmann T, Rychlik M. Chemical glucosylation of pyridoxine. Carbohydr Res 2020; 489:107929. [DOI: 10.1016/j.carres.2020.107929] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2019] [Revised: 01/27/2020] [Accepted: 01/27/2020] [Indexed: 11/28/2022]
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7
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Zhang W, Wang J, Serianni AS, Pan Q. A convenient synthesis of short-chain α-(1 → 2) mannopyranosyl oligosaccharides. Carbohydr Res 2020; 489:107897. [PMID: 32092558 PMCID: PMC7191533 DOI: 10.1016/j.carres.2019.107897] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2019] [Revised: 12/05/2019] [Accepted: 12/16/2019] [Indexed: 11/21/2022]
Abstract
Sugar 1,2-orthoesters are by-products of chemical glycosylation reactions that can be subsequently rearranged in situ to give trans glycosides. They have been used as donors in the synthesis of the latter glycosides with good regio- and stereo-selectivity. Alkyl α-(1 → 2) linked mannopyranosyl disaccharides have been reported as the major products from the rearrangement of mannopyranosyl orthoesters. Recent studies in this laboratory have shown that α-(1 → 2) linked mannopyranosyl di-, tri- and tetrasaccharides can be obtained in one step from mannopyranosyl allyl orthoester under optimized reaction conditions. In addition to the expected mono- and disaccharides (56%), allyl 2,3,4,6-tetra-O-acetyl-α-d-mannopyranosyl-(1 → 2)-3,4,6-tri-O-acetyl-α-d-mannopyranosyl-(1 → 2)-tri-O-acetyl-α-d-mannopyranoside and allyl 2,3,4,6-tetra-O-acetyl-α-d-mannopyranosyl-(1 → 2)-3,4,6-tri-O-acetyl-α-d-mannopyranosyl-(1 → 2)-3,4,6-tri-O-acetyl-α-d-mannopyranosyl-(1 → 2)-3,4,6-tri-O-acetyl-α-d-mannopyranoside were obtained in 23% and 6% isolated yields, respectively, from the oligomerization of a β-d-mannopyranosyl allyl 1,2-orthoester, along with small amounts of higher DP oligomers. Possible mechanisms for the oligomerization and side reactions are proposed based on NMR and mass spectrometric data.
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Affiliation(s)
- Wenhui Zhang
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN, 46556-5670, USA
| | - Jun Wang
- Omicron Biochemicals, Inc., 115 South Hill Street, South Bend, IN, 46617-2701, USA
| | - Anthony S Serianni
- Omicron Biochemicals, Inc., 115 South Hill Street, South Bend, IN, 46617-2701, USA; Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN, 46556-5670, USA
| | - Qingfeng Pan
- Omicron Biochemicals, Inc., 115 South Hill Street, South Bend, IN, 46617-2701, USA.
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8
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Ding Y, Vara Prasad CVNS, Wang B. Glycosylation on Unprotected or Partially Protected Acceptors. European J Org Chem 2020. [DOI: 10.1002/ejoc.201901675] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Yili Ding
- Life Science Department; Foshan University; 528000 Foshan Guangdong China
| | | | - Bingyun Wang
- Life Science Department; Foshan University; 528000 Foshan Guangdong China
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9
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Keith DJ, Townsend SD. Total Synthesis of the Congested, Bisphosphorylated Morganella morganii Zwitterionic Trisaccharide Repeating Unit. J Am Chem Soc 2019; 141:12939-12945. [PMID: 31329445 DOI: 10.1021/jacs.9b06830] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Zwitterionic polysaccharides (ZPSs) activate T-cell-dependent immune responses by major histocompatibility complex class II presentation. Herein, we report the first synthesis of a Morganella morganii ZPS repeating unit as an enabling tool in the synthesis of novel ZPS materials. The repeating unit incorporates a 1,2-cis-α-glycosidic bond; the problematic 1,2-trans-galactosidic bond, Gal-β-(1 → 3)-GalNAc; and phosphoglycerol and phosphocholine residues which have not been previously observed together as functional groups on the same oligosaccharide. The successful third-generation approach leverages a first in class glycosylation of a phosphoglycerol-functionalized acceptor. To install the phosphocholine unit, a highly effective phosphocholine donor was synthesized.
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Affiliation(s)
- D Jamin Keith
- Department of Chemistry , Vanderbilt University , Nashville , Tennessee 37235 , United States
| | - Steven D Townsend
- Department of Chemistry , Vanderbilt University , Nashville , Tennessee 37235 , United States
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10
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Wang L, Guo Z. An extensive review of studies on mycobacterium cell wall polysaccharide-related oligosaccharides – part I: Synthetic studies on arabinofuranosyl oligosaccharides. J Carbohydr Chem 2019. [DOI: 10.1080/07328303.2019.1630839] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
- Lizhen Wang
- Biology Institute, Qilu University of Technology (Shandong Academy of Sciences), Ji'nan, China
| | - Zhongwu Guo
- Department of Chemistry, University of Florida, Gainesville, FL, USA
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11
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Wałejko P, Baj A. The synthesis of vitamin E sugar 1,2-orthoesters. MONATSHEFTE FUR CHEMIE 2019. [DOI: 10.1007/s00706-018-2332-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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12
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Probing the Influence of Linker Length and Flexibility in the Design and Synthesis of New Trehalase Inhibitors. Molecules 2018; 23:molecules23020436. [PMID: 29462919 PMCID: PMC6017881 DOI: 10.3390/molecules23020436] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Revised: 02/12/2018] [Accepted: 02/14/2018] [Indexed: 12/22/2022] Open
Abstract
This work aims to synthesize new trehalase inhibitors selective towards the insect trehalase versus the porcine trehalase, in view of their application as potentially non-toxic insecticides and fungicides. The synthesis of a new pseudodisaccharide mimetic 8, by means of a stereoselective α-glucosylation of the key pyrrolizidine intermediate 13, was accomplished. The activity of compound 8 as trehalase inhibitor towards C. riparius trehalase was evaluated and the results showed that 8 was active in the μM range and showed a good selectivity towards the insect trehalase. To reduce the overall number of synthetic steps, simpler and more flexible disaccharide mimetics 9–11 bearing a pyrrolidine nucleus instead of the pyrrolizidine core were synthesized. The biological data showed the key role of the linker chain’s length in inducing inhibitory properties, since only compounds 9 (α,β-mixture), bearing a two-carbon atom linker chain, maintained activity as trehalase inhibitors. A proper change in the glucosyl donor-protecting groups allowed the stereoselective synthesis of the β-glucoside 9β, which was active in the low micromolar range (IC50 = 0.78 μM) and 12-fold more potent (and more selective) than 9α towards the insect trehalase.
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13
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Li Q, Guo Z. Pondering the Structural Factors that Affect 1,2- trans-Galactosylation: A Lesson Learnt from 3- O- β-Galactosylation of Galactosamine. J Carbohydr Chem 2017; 47:347-362. [PMID: 30174372 DOI: 10.1080/07328303.2017.1406095] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Stereoselective formation of glycosidic bonds remains one of the most challenging topics in carbohydrate chemistry. The predominant method for stereoselective construction of 1,2-trans-glycosidic bonds is through the neighboring group participation effect (NGPE), which proved to be less successful in synthesizing Galβ(1→3)GalNAc disaccharide. The steric effect that overshadows NGPE and the impacts of substituents at the 3-O- and 2-N-positions of donors and acceptors, respectively, on this synthesis were systematically examined to lead to some practical guidelines for choosing protecting groups towards the successful synthesis of Galβ(1→3)GalNAc and similar disaccharides.
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Affiliation(s)
- Qingjiang Li
- Department of Chemistry, University of Florida, 214 Leigh Hall, Gainesville, Florida 32611, United States
| | - Zhongwu Guo
- Department of Chemistry, University of Florida, 214 Leigh Hall, Gainesville, Florida 32611, United States
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14
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Okano A, Isley NA, Boger DL. Total Syntheses of Vancomycin-Related Glycopeptide Antibiotics and Key Analogues. Chem Rev 2017; 117:11952-11993. [PMID: 28437097 DOI: 10.1021/acs.chemrev.6b00820] [Citation(s) in RCA: 96] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
A review of efforts that have provided total syntheses of vancomycin and related glycopeptide antibiotics, their agylcons, and key analogues is provided. It is a tribute to developments in organic chemistry and the field of organic synthesis that not only can molecules of this complexity be prepared today by total synthesis but such efforts can be extended to the preparation of previously inaccessible key analogues that contain deep-seated structural changes. With the increasing prevalence of acquired bacterial resistance to existing classes of antibiotics and with the emergence of vancomycin-resistant pathogens (VRSA and VRE), the studies pave the way for the examination of synthetic analogues rationally designed to not only overcome vancomycin resistance but provide the foundation for the development of even more powerful and durable antibiotics.
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Affiliation(s)
- Akinori Okano
- Department of Chemistry and the Skaggs Institute for Chemical Biology, The Scripps Research Institute , 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Nicholas A Isley
- Department of Chemistry and the Skaggs Institute for Chemical Biology, The Scripps Research Institute , 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Dale L Boger
- Department of Chemistry and the Skaggs Institute for Chemical Biology, The Scripps Research Institute , 10550 North Torrey Pines Road, La Jolla, California 92037, United States
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15
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Khong DT, Judeh ZMA. Total synthesis of phenylpropanoid glycoside osmanthuside-B6 facilitated by double isomerisation of glucose–rhamnose orthoesters. Org Biomol Chem 2017; 15:2638-2646. [DOI: 10.1039/c7ob00198c] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Osmanthuside-B6 was synthesized in 22% overall yield. The synthesis involved a newly discovered glucose–rhamnose orthoester double isomerization process.
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Affiliation(s)
- Duc Thinh Khong
- School of Chemical and Biomedical Engineering
- Nanyang Technological University
- Singapore 637459
- Singapore
| | - Zaher M. A. Judeh
- School of Chemical and Biomedical Engineering
- Nanyang Technological University
- Singapore 637459
- Singapore
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17
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Li L, Xu Y, Milligan I, Fu L, Franckowiak EA, Du W. Synthesis of Highly pH-Responsive Glucose Poly(orthoester). Angew Chem Int Ed Engl 2013. [DOI: 10.1002/ange.201306391] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
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18
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Li L, Xu Y, Milligan I, Fu L, Franckowiak EA, Du W. Synthesis of Highly pH-Responsive Glucose Poly(orthoester). Angew Chem Int Ed Engl 2013; 52:13699-702. [DOI: 10.1002/anie.201306391] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2013] [Indexed: 11/11/2022]
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19
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Baldoni L, Marino C. Synthetic tools for the characterization of galactofuranosyl transferases: glycosylations via acylated glycosyl iodides. Carbohydr Res 2013; 374:75-81. [PMID: 23643834 DOI: 10.1016/j.carres.2013.03.032] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2012] [Revised: 03/26/2013] [Accepted: 03/28/2013] [Indexed: 02/04/2023]
Abstract
With the aim of developing synthetic tools for the characterization of galactofuranosyltransferases, the synthesis of 9-decenyl glycosides of D-Manp, D-Galf, and β-D-Galf-(1→3)-D-Manp was targeted. The interest in the alkenyl aglycone arises via potential conjugation reactions, once the terminal double bond has been conveniently functionalized. The glycosylation of β-D-Galf-(1→3)-D-Manp was attempted by two different approaches: the trichloroacetimidate method and the glycosylation via the glycosyl iodide. The conditions for the latter were established on the basis of glycosylation assays of per-O-acetylmannose. On the other hand, the study of glycosylation reactions via per-O-benzoylated galactofuranosyl iodide confirms the versatility of glycosyl iodides as donors.
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Affiliation(s)
- Luciana Baldoni
- CIHIDECAR-CONICET, Departamento de Química Orgánica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires 1428, Argentina
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Zhao J, Wei S, Yue A, Shao H. Environmentally Benign Synthesis of Sugar Orthoesters Promoted by Anhydrous Sodium Acetate and Ultrasound. CHINESE J CHEM 2012. [DOI: 10.1002/cjoc.201100385] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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21
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Wang G, Lu Z, Ding N, Zhang W, Wang P, Li Y. Differentiating the 2,3-diols of glucopyranosides by 4,6-O-benzylidene-protected-1,2-d-glucopyranosylorthoesters strategy. Carbohydr Res 2011; 346:2368-73. [DOI: 10.1016/j.carres.2011.08.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2011] [Revised: 08/01/2011] [Accepted: 08/08/2011] [Indexed: 11/25/2022]
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22
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Zhang J, Kong F. SYNTHESIS OF A XYLOSYLATED RHAMNOSE PENTASACCHARIDE—THE REPEATING UNIT OF THE O-SPECIFIC SIDE CHAIN OF LIPOPOLYSACCHARIDES FROM THE REFERENCE STRAINS FOR Stenotrophomonas maltophilia SEROGROUP O18. J Carbohydr Chem 2011. [DOI: 10.1081/car-120003740] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- Jianjun Zhang
- a Research Center for Eco-Environmental Science , Academia Sinica , P.O. Box 2871, Beijing, 100085, China
| | - Fanzuo Kong
- a Research Center for Eco-Environmental Science , Academia Sinica , P.O. Box 2871, Beijing, 100085, China
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23
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Lawandi J, Rocheleau S, Moitessier N. Directing/protecting groups mediate highly regioselective glycosylation of monoprotected acceptors. Tetrahedron 2011. [DOI: 10.1016/j.tet.2011.07.026] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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24
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Nakagawa A, Fenn D, Koschella A, Heinze T, Kamitakahara H. Synthesis of diblock methylcellulose derivatives with regioselective functionalization patterns. ACTA ACUST UNITED AC 2011. [DOI: 10.1002/pola.24952] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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25
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26
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Zhu YL, Kong FZ. Concise and Effective Synthesis of 1→2 α-Linked Mannopyranosyl Oligosaccharides and Related Antigenic Factor 34 and Dominant of Antigenic Factor 13. CHINESE J CHEM 2010. [DOI: 10.1002/cjoc.20010190122] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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27
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Wei S, Zhao J, Shao H. A facile method for the preparation of sugar orthoesters promoted by anhydrous sodium bicarbonate. CAN J CHEM 2009. [DOI: 10.1139/v09-146] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A facile and eco-friendly method for the preparation of sugar orthoesters by using anhydrous sodium bicarbonate is described. Various sugar orthoesers, including sugar–sugar orthoesters, were synthesized in good-to-excellent yields by the reaction of a protected glycosyl bromide with an alcohol or sugar.
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Affiliation(s)
- Shanqiao Wei
- Natural Products Research Centre, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041, China
| | - Jinzhong Zhao
- Natural Products Research Centre, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041, China
| | - Huawu Shao
- Natural Products Research Centre, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041, China
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28
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Synthetic studies on the trisaccharide intermediate of resin glycoside merremoside H2. Carbohydr Res 2009; 344:2063-8. [DOI: 10.1016/j.carres.2009.08.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2009] [Revised: 08/04/2009] [Accepted: 08/06/2009] [Indexed: 11/23/2022]
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29
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30
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31
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32
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Wang G, Zhang W, Lu Z, Wang P, Zhang X, Li Y. Convenient Synthesis of an N-Glycan Octasaccharide of the Bisecting Type. J Org Chem 2009; 74:2508-15. [DOI: 10.1021/jo900016j] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Guangfa Wang
- Key Laboratory of Marine Drugs, The Ministry of Education of China, School of Medicine and Pharmacy, Ocean University of China, Qingdao 266003, China
| | - Wei Zhang
- Key Laboratory of Marine Drugs, The Ministry of Education of China, School of Medicine and Pharmacy, Ocean University of China, Qingdao 266003, China
| | - Zhichao Lu
- Key Laboratory of Marine Drugs, The Ministry of Education of China, School of Medicine and Pharmacy, Ocean University of China, Qingdao 266003, China
| | - Peng Wang
- Key Laboratory of Marine Drugs, The Ministry of Education of China, School of Medicine and Pharmacy, Ocean University of China, Qingdao 266003, China
| | - Xiuli Zhang
- Key Laboratory of Marine Drugs, The Ministry of Education of China, School of Medicine and Pharmacy, Ocean University of China, Qingdao 266003, China
| | - Yingxia Li
- Key Laboratory of Marine Drugs, The Ministry of Education of China, School of Medicine and Pharmacy, Ocean University of China, Qingdao 266003, China
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33
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34
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Wang W, Kong F. Facile Synthesis of a Branched Trisaccharide–The Repeating Unit of Antigen O2 Polymer using Orthoester Formation - Rearrangement Strategy. J Carbohydr Chem 2008. [DOI: 10.1080/07328309908543994] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Affiliation(s)
- Wei Wang
- a Research Center for Eco-Environmental Sciences, Academia Sinica , P.O.Box 2871, Beijing 100085, P. R., China
| | - Fanzuo Kong
- a Research Center for Eco-Environmental Sciences, Academia Sinica , P.O.Box 2871, Beijing 100085, P. R., China
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35
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Concise synthesis of two trisaccharide analogs related to the glycone constituent of phanoside, a novel insulin releasing natural product. Tetrahedron 2007. [DOI: 10.1016/j.tet.2007.04.089] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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36
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Kojima M, Nakamura Y, Takeuchi S. A practical fluorous benzylidene acetal protecting group for a quick synthesis of disaccharides. Tetrahedron Lett 2007. [DOI: 10.1016/j.tetlet.2007.04.106] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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37
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Anas S, Sajisha VS, Rajan R, Kumaran RT, Radhakrishnan KV. Ionic Liquid [bmim]PF6-Mediated Synthesis of 1,2-Orthoesters of Carbohydrates and the Glycosidation Reactions of 4-Pentenyl Orthoesters. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2007. [DOI: 10.1246/bcsj.80.553] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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38
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Litjens REJN, van den Bos LJ, Codée JDC, Overkleeft HS, van der Marel GA. The use of cyclic bifunctional protecting groups in oligosaccharide synthesis—an overview. Carbohydr Res 2007; 342:419-29. [PMID: 17007825 DOI: 10.1016/j.carres.2006.09.002] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2006] [Revised: 08/30/2006] [Accepted: 09/01/2006] [Indexed: 11/27/2022]
Abstract
A historical overview is presented on stereo-directing effects of cis- and trans-fused diol protective groups used on both donor and acceptor glycosides. Attention is focused on the use of cyclic carbonates and carbamates, diacetals and acetals and finally the special case of 1,2-O-orthoesters and 1,2-O-cyanoalkylidene functionalised residues.
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Affiliation(s)
- Remy E J N Litjens
- Leiden Institute of Chemistry, Leiden University, PO Box 9502, 2333CC Leiden, The Netherlands
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39
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Kong F. Recent studies on reaction pathways and applications of sugar orthoesters in synthesis of oligosaccharides. Carbohydr Res 2007; 342:345-73. [PMID: 17109835 DOI: 10.1016/j.carres.2006.09.025] [Citation(s) in RCA: 95] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2006] [Accepted: 09/29/2006] [Indexed: 11/20/2022]
Abstract
Formation of sugar-sugar orthoesters consisting of a fully acylated mono- or disaccharide donor and a partially protected mono- or disaccharide acceptor is regioselective, and rearrangement of the orthoesters via RO-(orthoester)C bond cleavage gives a dioxolenium ion intermediate leading to 1,2-trans glycosidic linkage. The activity order of hydroxyl groups in the partially protected mannose and glucose acceptors is 6-OH>3-OH>2- or 4-OH. The coupling reactions with acylated glycosyl trichloroacetimidates as the donors usually give orthoesters as the intermediates specially when the coupling is carried out at slowed rates, and this is successfully used in regio- and stereoselective syntheses of oligosaccharides. Mannose and rhamnose orthoesters readily undergo O-2-(orthoester)C bond breaking, and this is used for synthesis of alpha-(1-->2)-linked oligosaccharides. (1-->3)-Glucosylation is special since the rearrangement of its sugar orthoester intermediates can occur with either RO-(orthoester)C bond cleavage with formation of the dioxolenium ion leading to 1,2-trans linkage, or C-1-O-1 bond cleavage leading to 1,2-cis linkage, and this is dependent upon the structures of donor and acceptor that compose the orthoester.
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Affiliation(s)
- Fanzuo Kong
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
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40
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Yamago S, Yamada T, Ito H, Hara O, Mino Y, Yoshida JI. Combinatorial synthesis of an oligosaccharide library by using beta-bromoglycoside-mediated iterative glycosylation of selenoglycosides: rapid expansion of molecular diversity with simple building blocks. Chemistry 2006; 11:6159-74. [PMID: 16075449 DOI: 10.1002/chem.200500126] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
A new method for constructing an oligosaccharide library composed of structurally defined oligosaccharides is presented based on an iterative glycosylation of selenoglycosides. Treatment of 2-acyl-protected selenoglycosides with bromine selectively generates beta-bromoglycosides, which serve as glycosyl cation equivalents in the oligosaccharide synthesis. Thus, the coupling of the bromoglycosides with another selenoglycoside affords the corresponding glycosylated selenoglycosides, which can be directly used to next glycosylation. The iteration of this sequence allows the synthesis of a variety of oligosaccharides including an elicitor active heptasaccharide. A characteristic feature of the iterative glycosylation is that glycosyl donors and acceptors with the same anomeric reactivity can be selectively coupled by activation of the glycosyl donor prior to coupling with the glycosyl acceptor. Therefore, same selenoglycosides can be used for both the glycosyl donors and the acceptors. This feature has been exemplified by a construction of an oligosaccharide library directed to elicitor-active oligosaccharides. The library composed of stereochemically defined oligoglucosides with considerable structural diversity can be constructed starting from simple selenoglycosides.
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Affiliation(s)
- Shigeru Yamago
- Division of Molecular Materials Science, Graduate School of Science, Osaka City University, Japan.
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41
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Ravidà A, Liu X, Kovacs L, Seeberger PH. Synthesis of Glycosyl Phosphates from 1,2-Orthoesters and Application to in Situ Glycosylation Reactions. Org Lett 2006; 8:1815-8. [PMID: 16623558 DOI: 10.1021/ol0603155] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
[reaction: see text] A series of glycosyl phosphates were prepared in high yield by treatment of the corresponding 1,2-orthoesters with dibutyl phosphate. Glycosyl phosphates are efficient glycosylating agents even when used in crude form or when generated in situ. The immunodominant epitope trirhamnoside of group B Streptococcus was prepared to demonstrate the synthetic utility of the method.
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Affiliation(s)
- Alessandra Ravidà
- Laboratorium für Organische Chemie, Swiss Federal Institute of Technology, ETH Zürich, HCI F315, Wolfgang-Pauli Strasse 10, 8093 Zürich, Switzerland
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42
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Zhao W, Kong F. Synthesis of a heptasaccharide fragment of the O-deacetylated GXM of C. neoformans serotype C. Carbohydr Res 2005; 340:1673-81. [PMID: 15927170 DOI: 10.1016/j.carres.2005.05.003] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2005] [Accepted: 05/01/2005] [Indexed: 10/25/2022]
Abstract
Beta-D-Xylp-(1-->2)-alpha-D-Manp-(1-->3)-[beta-D-Xylp-(1-->2)][beta-D-Xylp-(1-->4)]-alpha-D-Manp-(1-->3)-[beta-D-Xylp-(1-->4)]-alpha-D-Manp, the fragment of the exopolysaccharide from Cryptococcus neoformans serovar C, was synthesized as its methyl glycoside. Thus, chloroacetylation of allyl 3-O-acetyl-4,6-O-benzylidene-alpha-D-mannopyranoside (1) followed by debenzylidenation and selective 6-O-benzoylation afforded allyl 2-O-chloroacetyl-3-O-acetyl-6-O-benzoyl-alpha-D-mannopyranoside (4). Glycosylation of 4 with 2,3,4-tri-O-benzoyl-D-xylopyranosyl trichloroacetimidate (5) furnished the beta-(1-->4)-linked disaccharide 6. Dechloroacetylation gave the disaccharide acceptor 7 and subsequent coupling with 5 produced the trisaccharide 8. Deacetylation of 8 gave the trisaccharide acceptor 9 and subsequent coupling with a disaccharide 10 produced the pentasaccharide 11. Reiteration of deallylation and trichloroacetimidate formation from 11 yielded the pentasaccharide donor 12. Coupling of a disaccharide acceptor 13 with 12 afforded the heptasaccharide 14. Subsequent deprotection gave the heptaoside 16, while selective 2-O-deacetylation of 14 gave the heptasaccharide acceptor 15. Condensation of 15 with glucopyranosyluronate imidate 17 did not yield the expected octaoside, instead, an orthoester product 18 was obtained. Rearrangement of 18 did not give the target octaoside; but produced 15. Meanwhile, there was no reaction between 15 and the glycosyl bromide donor 19.
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Affiliation(s)
- Wei Zhao
- Research Center for Eco-Environmental Sciences, Academia Sinica, PO Box 2871, Beijing 100085, China
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43
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Yu H, Williams DL, Ensley HE. 4-Acetoxy-2,2-dimethylbutanoate: a useful carbohydrate protecting group for the selective formation of β-(1→3)-d-glucans. Tetrahedron Lett 2005; 46:3417-3421. [PMID: 26236049 DOI: 10.1016/j.tetlet.2005.03.099] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
The use of 4-acetoxy-2,2-dimethylbutanoyl protecting group for the C2-hydroxyl allows the selective formation of β-glycosides without producing α-glycosides. This very bulky protecting group can be removed under mild conditions.
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Affiliation(s)
- Hai Yu
- Department of Chemistry, Tulane University, New Orleans, LA 70118, USA
| | - David L Williams
- Department of Surgery, East Tennessee State University, Johnson City, TN 37614, USA
| | - Harry E Ensley
- Department of Chemistry, Tulane University, New Orleans, LA 70118, USA
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44
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Mari S, Posteri H, Marcou G, Potenza D, Micheli F, Cañada F, Jimenez-Barbero J, Bernardi A. Synthesis, Conformational Studies and Mannosidase Stability of a Mimic of 1,2-Mannobioside. European J Org Chem 2004. [DOI: 10.1002/ejoc.200400520] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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45
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Fairweather JK, Karoli T, Ferro V. The synthesis of phosphorylated disaccharide components of the extracellular phosphomannan of Pichia (Hansenula) holstii NRRL Y-2448. Bioorg Med Chem 2004; 12:6063-75. [PMID: 15519152 DOI: 10.1016/j.bmc.2004.09.005] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2004] [Accepted: 09/08/2004] [Indexed: 11/15/2022]
Abstract
Methods for the stereoselective synthesis of alpha-(1-->2)- and alpha-(1-->3)-linked 6(II)-O-phosphomannobiosides were developed. Two strategies were successfully employed: a D-mannosyl acceptor was coupled with a phosphorylated D-mannosyl trichloroacetimidate donor, or alternatively with a differentially 6-O-protected D-mannosyl trichloroacetimidate donor which, after glycosylation, was selectively deprotected and phosphorylated. Two target phosphomannobiosides intended for use in SAR studies of the antiangiogenic drug candidate PI-88, 2-O-(6-O-phospho-alpha-D-mannopyranosyl)-D-mannopyranose and methyl 3-O-(6-O-phospho-alpha-D-mannopyranosyl)-alpha-D-mannopyranoside, were synthesized. The former is a minor component of the side-chain repeating unit of the extracellular phosphomannan of Pichia (Hansenula) holstii NRRL Y-2448, whilst the latter represents a nonreducing end fragment of the phosphomannan.
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Affiliation(s)
- Jon K Fairweather
- Drug Design Group, Progen Industries Ltd, 2806 Ipswich Road, Darra, Queensland 4076, Australia
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46
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An environmentally benign and practical synthesis of sugar orthoesters promoted by potassium fluoride. Tetrahedron Lett 2004. [DOI: 10.1016/j.tetlet.2004.09.175] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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47
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Gung BW, Fox RM. Total synthesis of bidensyneosides A2 and C: remarkable protecting group effects in glycosylation. Tetrahedron 2004. [DOI: 10.1016/j.tet.2004.08.012] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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48
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Fraser-Reid B, Grimme S, Piacenza M, Mach M, Schlueter U. Orthoesters versus 2-O-Acyl Glycosides as Glycosyl Donors: Theorectical and Experimental Studies. Chemistry 2003; 9:4687-92. [PMID: 14566874 DOI: 10.1002/chem.200304856] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
n-Pentenyl orthoesters (NPOEs) undergo routine acid catalyzed rearrangement into 2-O-acyl n-pentenyl glycosides (NPGs). The reactant and product can both function as glycosyl donors affording 1,2-trans linked glycosides predominantly. However, both donors differ in their rates of reactions, the yields they produce, and the nature of their byproducts, indicating that the NPOE/NPG pair may not be reacting through the same intermediates. We have therefore applied quantum chemical calculations using DFT methods and MP second order perturbation theory to learn more about orthoesters and their 2-O-acyl glycosidic counterparts. The calculations show that in the case of a manno NPG and NPOE pair, each donor goes initially to a different cationic intermediate. Thus, the former goes to a high-energy oxocarbenium ion before descending to a trioxolenium ion in which the charge is distributed over the pyrano ring oxygen, as well as the carbonyl and ether oxygen atoms of the putative C2 ester. On the other hand, ionization of the NPOE produces a dioxolenium ion lying slightly above the more stable trioxolenium counterpart. For the gluco pair, the NPG also goes to a very high-energy oxocarbenium ion, which also descends to a trioxolenium ion. However, unlike the manno analogue, the gluco NPOE does not give a dioxolenium ion; indeed, the dioxolenium is not energetically distinguishable from the trioxolenium counterpart. The theoretical observations have been tested experimentally. Thus, it was found that with manno derivatives, the orthoester is a more reactive donor than the corresponding NPG donor, whereas, for gluco derivatives, there is no advantage to using one over the other, unless one resorts to carefully selected promoters.
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Affiliation(s)
- Bert Fraser-Reid
- Natural Products and Glycotechnology Research Institute Inc. (NPG), 4118 Swarthmore Road, Durham, NC 27707, USA.
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49
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Dellagreca M, Fiorentino A, Monaco P, Previtera L, Temussi F, Zarrelli A. Synthesis of degraded cyanogenic glycosides from Sambucus nigra. Nat Prod Res 2003; 17:177-81. [PMID: 12737401 DOI: 10.1080/1057563021000040772] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Two natural cyanohydrins, isolated from Sambucus nigra, have been synthesised from mandelonitrile and penta-O-acetyl-beta-galactopyranose. The synthesis confirmed the stereochemistry of the compounds, which had been assigned on biogenetic grounds.
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Affiliation(s)
- Marina Dellagreca
- Dipartimento di Chimica Organica e Biochimica, Università Federico II, Complesso Universitario Monte S. Angelo, Via Cinthia, 1-80134 Napoli, Italy
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50
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Vidal S, Morère A, Montero JL. A convenient synthetic route to mannose 6-phosphonate-cholesteryl conjugate. HETEROATOM CHEMISTRY 2003. [DOI: 10.1002/hc.10134] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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