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Maji S, Ghotekar BK, Kulkarni SS. Total Synthesis of a Conjugation-Ready Tetrasaccharide Repeating Unit of Vibrio cholerae O:3 O-antigen Polysaccharide. Org Lett 2024; 26:745-750. [PMID: 38198674 DOI: 10.1021/acs.orglett.3c04225] [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: 01/12/2024]
Abstract
Herein, we report the first total synthesis of the tetrasaccharide repeating unit of Vibrio cholerae O:3 O-antigen polysaccharide. The highly complex tetrasaccharide contains rare amino sugars such as d-bacillosamine and l-fucosamine, highly labile sugar ascarylose, and higher carbon sugar d-d-heptose. Stereoselective glycosylation of the notoriously reactive ascarylose with d-d-heptose, poor nucleophilicity of the axial C4-OH of l-fucosamine, and amide coupling are the key challenges encountered in the total synthesis, which was completed via a longest linear sequence of 23 steps in 4.2% overall yield.
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Affiliation(s)
- Soumyakanta Maji
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai, 400076, India
| | - Balasaheb K Ghotekar
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai, 400076, India
| | - Suvarn S Kulkarni
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai, 400076, India
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2
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Luo S, Liu Y, Hao T, Ma W, Luo Y, Wang S, Xu Z, Hu C, Wen L, Li T. Chemoenzymatic Total Synthesis of Haemophilus ducreyi Lipooligosaccharide Core Octasaccharides Containing Natural and Unnatural Sialic Acids. Org Lett 2023; 25:2312-2317. [PMID: 36972419 DOI: 10.1021/acs.orglett.3c00657] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/29/2023]
Abstract
The first total synthesis of Haemophilus ducreyi lipooligosaccharide core octasaccharides containing natural and unnatural sialic acids has been achieved by an efficient chemoenzymatic approach. A highly convergent [3 + 3] coupling strategy was developed to chemically assemble a unique hexasaccharide bearing multiple rare higher-carbon sugars d-glycero-d-manno-heptose (d,d-Hep), l-glycero-d-manno-heptose (l,d-Hep), and 3-deoxy-α-d-manno-oct-2-ulosonic acid (Kdo). Key features include sequential one-pot glycosylations for oligosaccharide assembly and the construction of the challenging α-(1 → 5)-linked Hep-Kdo glycosidic bond by gold-catalyzed glycosylation with a glycosyl ortho-alkynylbenzoate donor. Furthermore, the sequential enzyme-catalyzed regio- and stereoselective introduction of a galactose residue using β-1,4-galactosyltransferase and different sialic acids using a one-pot multienzyme sialylation system was efficiently accomplished to provide the target octasaccharides.
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Affiliation(s)
- Shiwei Luo
- School of Chinese Materia Medica, Nanjing University of Chinese Medicine, Nanjing, Jiangsu 210023, China
| | - Yating Liu
- School of Chinese Materia Medica, Nanjing University of Chinese Medicine, Nanjing, Jiangsu 210023, China
| | - Tianhui Hao
- Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Wenjing Ma
- Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yawen Luo
- Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Shasha Wang
- School of Chinese Materia Medica, Nanjing University of Chinese Medicine, Nanjing, Jiangsu 210023, China
| | - Zhuojia Xu
- Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Chaoyu Hu
- Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Liuqing Wen
- Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
- School of Chinese Materia Medica, Nanjing University of Chinese Medicine, Nanjing, Jiangsu 210023, China
| | - Tiehai Li
- Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
- School of Chinese Materia Medica, Nanjing University of Chinese Medicine, Nanjing, Jiangsu 210023, China
- University of Chinese Academy of Sciences, Beijing 100049, China
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3
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Meng S, Hettiarachchi IL, Bhetuwal BR, Thapa P, Zhu J. Stereoselective Synthesis of β-d-Manno-heptopyranoside via Cs 2CO 3-Mediated Anomeric O-Alkylation: Synthesis of a Tetrasaccharide Repeat Unit of Bacillus thermoaerophilus Surface-Layer Glycoprotein. J Org Chem 2022; 87:6588-6600. [PMID: 35537215 DOI: 10.1021/acs.joc.2c00168] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Stereoselective synthesis of d-glycero- and l-glycero-β-d-mannoheptosides has been achieved by cesium carbonate-mediated β-selective anomeric O-alkylation of the corresponding d-mannoheptoses. In addition, this method has been utilized in the total synthesis of a tetrasaccharide repeat unit of Bacillus thermoaerophilus surface-layer glycoprotein.
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Affiliation(s)
- Shuai Meng
- Department of Chemistry and Biochemistry and School of Green Chemistry and Engineering, The University of Toledo, 2801 W. Bancroft Street, Toledo, Ohio 43606, United States
| | - Ishani Lakshika Hettiarachchi
- Department of Chemistry and Biochemistry and School of Green Chemistry and Engineering, The University of Toledo, 2801 W. Bancroft Street, Toledo, Ohio 43606, United States
| | - Bishwa Raj Bhetuwal
- Department of Chemistry and Biochemistry and School of Green Chemistry and Engineering, The University of Toledo, 2801 W. Bancroft Street, Toledo, Ohio 43606, United States
| | - Prakash Thapa
- Department of Chemistry and Biochemistry and School of Green Chemistry and Engineering, The University of Toledo, 2801 W. Bancroft Street, Toledo, Ohio 43606, United States
| | - Jianglong Zhu
- Department of Chemistry and Biochemistry and School of Green Chemistry and Engineering, The University of Toledo, 2801 W. Bancroft Street, Toledo, Ohio 43606, United States
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4
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Crich D. En Route to the Transformation of Glycoscience: A Chemist's Perspective on Internal and External Crossroads in Glycochemistry. J Am Chem Soc 2021; 143:17-34. [PMID: 33350830 PMCID: PMC7856254 DOI: 10.1021/jacs.0c11106] [Citation(s) in RCA: 64] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Carbohydrate chemistry is an essential component of the glycosciences and is fundamental to their progress. This Perspective takes the position that carbohydrate chemistry, or glycochemistry, has reached three crossroads on the path to the transformation of the glycosciences, and illustrates them with examples from the author's and other laboratories. The first of these potential inflexion points concerns the mechanism of the glycosylation reaction and the role of protecting groups. It is argued that the experimental evidence supports bimolecular SN2-like mechanisms for typical glycosylation reactions over unimolecular ones involving stereoselective attack on naked glycosyl oxocarbenium ions. Similarly, it is argued that the experimental evidence does not support long-range stereodirecting participation of remote esters through bridged bicyclic dioxacarbenium ions in organic solution in the presence of typical counterions. Rational design and improvement of glycosylation reactions must take into account the roles of the counterion and of concentration. A second crossroads is that between mainstream organic chemistry and glycan synthesis. The case is made that the only real difference between glycan and organic synthesis is the formation of C-O rather than C-C bonds, with diastereocontrol, strategy, tactics, and elegance being of critical importance in both areas: mainstream organic chemists should feel comfortable taking this fork in the road, just as carbohydrate chemists should traveling in the opposite direction. A third crossroads is that between carbohydrate chemistry and medicinal chemistry, where there are equally many opportunities for traffic in either direction. The glycosciences have advanced enormously in the past decade or so, but creativity, input, and ingenuity of scientists from all fields is needed to address the many sophisticated challenges that remain, not the least of which is the development of a broader and more general array of stereospecific glycosylation reactions.
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Affiliation(s)
- David Crich
- Department of Pharmaceutical and Biomedical Sciences, University of Georgia, 250 West Green Street, Athens, Georgia 30602, United States
- Department of Chemistry, University of Georgia, 140 Cedar Street, Athens, Georgia 30602, United States
- Complex Carbohydrate Research Center, University of Georgia, 315 Riverbend Road, Athens, Georgia 30602, United States
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Yoshida F, Yoshinaka H, Tanaka H, Hanashima S, Yamaguchi Y, Ishihara M, Saburomaru M, Kato Y, Saito R, Ando H, Kiso M, Imamura A, Ishida H. Synthesis of the Core Oligosaccharides of Lipooligosaccharides from
Campylobacter jejuni
: A Putative Cause of Guillain–Barré Syndrome. Chemistry 2018; 25:796-805. [DOI: 10.1002/chem.201804862] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2018] [Indexed: 11/06/2022]
Affiliation(s)
- Fumi Yoshida
- Department of Applied Bio-organic ChemistryGifu University 1-1 Yanagido Gifu-shi Gifu 501-1193 Japan
| | - Hiroki Yoshinaka
- Department of Applied Bio-organic ChemistryGifu University 1-1 Yanagido Gifu-shi Gifu 501-1193 Japan
| | - Hidenori Tanaka
- Center for Highly Advanced Integration and Nano and Life Sciences, (G-CHAIN)Gifu University 1-1 Yanagido Gifu-shi Gifu 501-1193 Japan
| | - Shinya Hanashima
- Structural Glycobiology Team, Systems Glycobiology Research GroupRIKEN Global Research Cluster 2-1 Hirosawa Wako Saitama 351-0198 Japan
| | - Yoshiki Yamaguchi
- Structural Glycobiology Team, Systems Glycobiology Research GroupRIKEN Global Research Cluster 2-1 Hirosawa Wako Saitama 351-0198 Japan
| | - Mikio Ishihara
- Department of Applied Bio-organic ChemistryGifu University 1-1 Yanagido Gifu-shi Gifu 501-1193 Japan
| | - Miyuki Saburomaru
- Department of Applied Bio-organic ChemistryGifu University 1-1 Yanagido Gifu-shi Gifu 501-1193 Japan
| | - Yuki Kato
- Department of Applied Bio-organic ChemistryGifu University 1-1 Yanagido Gifu-shi Gifu 501-1193 Japan
| | - Risa Saito
- Department of Applied Bio-organic ChemistryGifu University 1-1 Yanagido Gifu-shi Gifu 501-1193 Japan
| | - Hiromune Ando
- Center for Highly Advanced Integration and Nano and Life Sciences, (G-CHAIN)Gifu University 1-1 Yanagido Gifu-shi Gifu 501-1193 Japan
| | - Makoto Kiso
- Department of Applied Bio-organic ChemistryGifu University 1-1 Yanagido Gifu-shi Gifu 501-1193 Japan
| | - Akihiro Imamura
- Department of Applied Bio-organic ChemistryGifu University 1-1 Yanagido Gifu-shi Gifu 501-1193 Japan
| | - Hideharu Ishida
- Department of Applied Bio-organic ChemistryGifu University 1-1 Yanagido Gifu-shi Gifu 501-1193 Japan
- Center for Highly Advanced Integration and Nano and Life Sciences, (G-CHAIN)Gifu University 1-1 Yanagido Gifu-shi Gifu 501-1193 Japan
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6
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Tohda K, Saito M, Sakai H, Ishikura D, Saito R, Sasaki K. NMR characterization of α- and β-mannopyranurono-2,6-lactones. Tetrahedron 2018. [DOI: 10.1016/j.tet.2018.06.014] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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8
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Maier L, Khirsariya P, Hylse O, Adla SK, Černová L, Poljak M, Krajčovičová S, Weis E, Drápela S, Souček K, Paruch K. Diastereoselective Flexible Synthesis of Carbocyclic C-Nucleosides. J Org Chem 2017; 82:3382-3402. [PMID: 28267331 DOI: 10.1021/acs.joc.6b02594] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Carbocyclic C-nucleosides are quite rare. Our route enables flexible preparation of three classes of these nucleoside analogs from common precursors-properly substituted cyclopentanones, which can be prepared racemic (in six steps) or optically pure (in ten steps) from inexpensive norbornadiene. The methodology allows flexible manipulation of individual positions around the cyclopentane ring, namely highly diastereoselective installation of carbo- and heterocyclic substituents at position 1', orthogonal functionalization of position 5', and efficient inversion of stereochemistry at position 2'. Newly prepared carbocyclic C-analog of tubercidine, profiled in MCF7 (breast cancer) and HFF1 (human foreskin fibroblasts) cell cultures, is less potent than tubercidine itself, but more selectively toxic toward the tumorigenic cells.
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Affiliation(s)
- Lukáš Maier
- Department of Chemistry, CZ Openscreen, Faculty of Science, Masaryk University , Kamenice 5/A8, 625 00 Brno, Czech Republic.,International Center for Clinical Research, St. Anne's University Hospital Brno , Pekařská 53, 656 91 Brno, Czech Republic
| | - Prashant Khirsariya
- Department of Chemistry, CZ Openscreen, Faculty of Science, Masaryk University , Kamenice 5/A8, 625 00 Brno, Czech Republic.,International Center for Clinical Research, St. Anne's University Hospital Brno , Pekařská 53, 656 91 Brno, Czech Republic
| | - Ondřej Hylse
- Department of Chemistry, CZ Openscreen, Faculty of Science, Masaryk University , Kamenice 5/A8, 625 00 Brno, Czech Republic.,International Center for Clinical Research, St. Anne's University Hospital Brno , Pekařská 53, 656 91 Brno, Czech Republic
| | - Santosh Kumar Adla
- Department of Chemistry, CZ Openscreen, Faculty of Science, Masaryk University , Kamenice 5/A8, 625 00 Brno, Czech Republic
| | - Lenka Černová
- Department of Chemistry, CZ Openscreen, Faculty of Science, Masaryk University , Kamenice 5/A8, 625 00 Brno, Czech Republic
| | - Michal Poljak
- Department of Chemistry, CZ Openscreen, Faculty of Science, Masaryk University , Kamenice 5/A8, 625 00 Brno, Czech Republic
| | - Soňa Krajčovičová
- Department of Chemistry, CZ Openscreen, Faculty of Science, Masaryk University , Kamenice 5/A8, 625 00 Brno, Czech Republic
| | - Erik Weis
- Department of Chemistry, CZ Openscreen, Faculty of Science, Masaryk University , Kamenice 5/A8, 625 00 Brno, Czech Republic
| | - Stanislav Drápela
- Department of Cytokinetics, Institute of Biophysics, Academy of Sciences of the Czech Republic , Královopolská 135, 612 00 Brno, Czech Republic
| | - Karel Souček
- International Center for Clinical Research, St. Anne's University Hospital Brno , Pekařská 53, 656 91 Brno, Czech Republic.,Department of Cytokinetics, Institute of Biophysics, Academy of Sciences of the Czech Republic , Královopolská 135, 612 00 Brno, Czech Republic
| | - Kamil Paruch
- Department of Chemistry, CZ Openscreen, Faculty of Science, Masaryk University , Kamenice 5/A8, 625 00 Brno, Czech Republic.,International Center for Clinical Research, St. Anne's University Hospital Brno , Pekařská 53, 656 91 Brno, Czech Republic
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9
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Fascione MA, Brabham R, Turnbull WB. Mechanistic Investigations into the Application of Sulfoxides in Carbohydrate Synthesis. Chemistry 2016; 22:3916-28. [PMID: 26744250 PMCID: PMC4794778 DOI: 10.1002/chem.201503504] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2015] [Indexed: 12/04/2022]
Abstract
The utility of sulfoxides in a diverse range of transformations in the field of carbohydrate chemistry has seen rapid growth since the first introduction of a sulfoxide as a glycosyl donor in 1989. Sulfoxides have since developed into more than just anomeric leaving groups, and today have multiple roles in glycosylation reactions. These include as activators for thioglycosides, hemiacetals, and glycals, and as precursors to glycosyl triflates, which are essential for stereoselective β-mannoside synthesis, and bicyclic sulfonium ions that facilitate the stereoselective synthesis of α-glycosides. In this review we highlight the mechanistic investigations undertaken in this area, often outlining strategies employed to differentiate between multiple proposed reaction pathways, and how the conclusions of these investigations have and continue to inform upon the development of more efficient transformations in sulfoxide-based carbohydrate synthesis.
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Affiliation(s)
- Martin A Fascione
- York Structural Biology Lab, Department of Chemistry, University of York, Heslington Road, York, YO10 5DD, UK.
| | - Robin Brabham
- York Structural Biology Lab, Department of Chemistry, University of York, Heslington Road, York, YO10 5DD, UK
| | - W Bruce Turnbull
- School of Chemistry and Astbury Centre for Structural Molecular Biology, University of Leeds, Woodhouse Lane, Leeds, LS2 9JT, UK.
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10
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Gou S, Yin T, Ye Z, Jiang W, Yang C, Xia Q, Wu M. Water-soluble allyl and diallyl camphor sulfonamides-based polyacrylamide copolymers for enhanced oil recovery. J Appl Polym Sci 2014. [DOI: 10.1002/app.41238] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Shaohua Gou
- State Key Lab of Oil and Gas Reservoir Geology and Exploitation; Southwest Petroleum University; Chengdu 610500 People's Republic of China
- School of Chemistry and Chemical Engineering, Southwest Petroleum University; Chengdu 610500 People's Republic of China
| | - Ting Yin
- School of Chemistry and Chemical Engineering, Southwest Petroleum University; Chengdu 610500 People's Republic of China
| | - Zhongbin Ye
- State Key Lab of Oil and Gas Reservoir Geology and Exploitation; Southwest Petroleum University; Chengdu 610500 People's Republic of China
- School of Chemistry and Chemical Engineering, Southwest Petroleum University; Chengdu 610500 People's Republic of China
| | - Wenchao Jiang
- School of Chemistry and Chemical Engineering, Southwest Petroleum University; Chengdu 610500 People's Republic of China
| | - Cheng Yang
- School of Chemistry and Chemical Engineering, Southwest Petroleum University; Chengdu 610500 People's Republic of China
| | - Qiang Xia
- School of Chemistry and Chemical Engineering, Southwest Petroleum University; Chengdu 610500 People's Republic of China
| | - Mingfang Wu
- School of Chemistry and Chemical Engineering, Southwest Petroleum University; Chengdu 610500 People's Republic of China
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11
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Tamigney Kenfack M, Blériot Y, Gauthier C. Intramolecular Aglycon Delivery Enables the Synthesis of 6-Deoxy-β-d-manno-heptosides as Fragments of Burkholderia pseudomallei and Burkholderia mallei Capsular Polysaccharide. J Org Chem 2014; 79:4615-34. [DOI: 10.1021/jo500640n] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Marielle Tamigney Kenfack
- Université de Poitiers, Institut de Chimie IC2MP, UMR-CNRS 7285, Équipe Synthèse Organique, 4 rue Michel
Brunet, 86073 Poitiers, France
| | - Yves Blériot
- Université de Poitiers, Institut de Chimie IC2MP, UMR-CNRS 7285, Équipe Synthèse Organique, 4 rue Michel
Brunet, 86073 Poitiers, France
| | - Charles Gauthier
- Université de Poitiers, Institut de Chimie IC2MP, UMR-CNRS 7285, Équipe Synthèse Organique, 4 rue Michel
Brunet, 86073 Poitiers, France
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12
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Improved methods for the stereoselective synthesis of mannoheptosyl donors and their glycosides: toward the synthesis of the trisaccharide repeating unit of the Campylobacter jejuni RM1221 capsular polysaccharide. Tetrahedron 2013. [DOI: 10.1016/j.tet.2013.04.094] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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13
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Bhatia S, Mohr A, Mathur D, Parmar VS, Haag R, Prasad AK. Biocatalytic route to sugar-PEG-based polymers for drug delivery applications. Biomacromolecules 2011; 12:3487-98. [PMID: 21834595 DOI: 10.1021/bm200647a] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Sugar-PEG-based polymers were synthesized by enzymatic copolymerization of 4-C-hydroxymethyl-1,2-O-isopropylidene-β-L-threo-pentofuranose/4-C-hydroxymethyl-1,2-O-benzylidene-β-L-threo-pentofuranose/4-C-hydroxymethyl-1,2-O-isopropylidene-3-O-pentyl-β-L-threo-pentofuranose with PEG-600 dimethyl ester using Novozyme-435 (Candida antarctica lipase immobilized on polyacrylate). Carbohydrate monomers were obtained by the multistep synthesis starting from diacetone-D-glucose and PEG-600 dimethyl ester, which was in turn obtained by the esterification of the commercially available PEG-600 diacid. Aggregation studies on the copolymers revealed that in aqueous solution those polymers bearing the hydrophobic pentyl/benzylidene moiety spontaneously self-assembled into supramolecular aggregates. The critical aggregation concentration (CAC) of polymers was determined by surface tension measurements, and the precise size of the aggregates was obtained by dynamic light scattering. The polymeric aggregates were further explored for their drug encapsulation properties in buffered aqueous solution of pH 7.4 (37 °C) using nile red as a hydrophobic model compound by means of UV/vis and fluorescence spectroscopy. There was no significant encapsulation in polymer synthesized from 4-C-hydroxymethyl-1,2-O-isopropylidene-β-L-threo-pentofuranose because this sugar monomer does not contain a big hydrophobic moiety as the pentyl or the benzylidene moiety. Nile red release study was performed at pH 5.0 and 7.4 using fluorescence spectroscopy. The release of nile red from the polymer bearing benzylidene moiety and pentyl moiety was observed with a half life of 3.4 and 2.0 h, respectively at pH 5.0, whereas no release was found at pH 7.4.
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Affiliation(s)
- Sumati Bhatia
- Bioorganic Laboratory, Department of Chemistry, University of Delhi, Delhi 110 007, India
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Szikra D, Mándi A, Borbás A, Nagy IP, Komáromi I, Kiss-Szikszai A, Herczeg M, Antus S. A kinetic study on the reductive opening of the diphenylmethylene acetal in methyl 2,3-O-diphenylmethylene-α-l-rhamnopyranoside. Carbohydr Res 2011; 346:2004-6. [DOI: 10.1016/j.carres.2011.04.041] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2011] [Revised: 04/18/2011] [Accepted: 04/27/2011] [Indexed: 11/17/2022]
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15
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Crich D, Picard S. Highly stereoselective synthesis of alpha-D-mannopyranosyl phosphosugars. J Org Chem 2010; 74:9576-9. [PMID: 19924835 DOI: 10.1021/jo902254w] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Alpha-mannopyranosyl phosphosugars are obtained in 61-90% yields from 4,6-O-benzylidene-protected mannosyl thioglycosides bearing ester functionality in the 3-O-position by coupling reactions with ammonium salts of phosphosugars on activation with 1-benzenesulfinyl piperidine, 2,4,6-tri-tert-butylpyrimidine, and trifluoromethanesulfonic anhydride. Due to the presence of the disarming ester group, only the formation of the alpha-isomer was observed.
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Affiliation(s)
- David Crich
- Centre de Recherche de Gif, Institut de Chimie des Substances Naturelles, CNRS, 1 avenue de la Terrasse, 91198 Gif-sur-Yvette, France.
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