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Thangsan P, Rukkijakan T, Thanaussavadate B, Yiamsawat K, Sirijaraensre J, Gable KP, Chuawong P. Quantitative analysis of steric effects on the regioselectivity of the Larock heteroannulation reaction. Org Biomol Chem 2023; 21:1501-1513. [PMID: 36688538 DOI: 10.1039/d2ob02089k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Alkylphenylacetylene derivatives were synthesized and used as reactants in the Larock heteroannulation reaction to investigate the steric influence on regioselectivity. Large alkyl groups preferentially yielded 2-alkyl-3-phenylindole products, while smaller alkyl groups provided 3-alkyl-2-phenylindole as major products. The logarithm of regioisomeric product ratios exhibited good correlations with various steric parameters. Notably, the Charton values provided the best correlation when excluding the cyclopropyl group. In addition, the Boltzmann-weighted Sterimol parameter (wSterimol) was utilized to generate a good predictive model, indicating the B1 wSterimol as the significant regiochemical determining parameter with no obvious deviation for the cyclopropyl group. Relative atomic distances within the DFT-optimized transition state structures revealed good correlations with the logarithm of regioisomeric ratios. Furthermore, the cyclopropyl adsorption complex indicated electronic contribution, explaining the peculiar behavior of this substituent in the experimental observation.
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Affiliation(s)
- Poomsith Thangsan
- Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Special Research Unit for Advanced Magnetic Resonance (AMR), Kasetsart University, Bangkok 10900, Thailand.
| | - Thanya Rukkijakan
- Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Special Research Unit for Advanced Magnetic Resonance (AMR), Kasetsart University, Bangkok 10900, Thailand.
| | - Bongkotrat Thanaussavadate
- Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Special Research Unit for Advanced Magnetic Resonance (AMR), Kasetsart University, Bangkok 10900, Thailand.
| | - Kanyapat Yiamsawat
- Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Special Research Unit for Advanced Magnetic Resonance (AMR), Kasetsart University, Bangkok 10900, Thailand.
| | - Jakkapan Sirijaraensre
- Department of Chemistry, Faculty of Science, Kasetsart University, Bangkok 10900, Thailand
| | - Kevin P Gable
- Department of Chemistry, Oregon State University, 153 Gilbert Hall, Corvallis, Oregon 97331-4003, USA
| | - Pitak Chuawong
- Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Special Research Unit for Advanced Magnetic Resonance (AMR), Kasetsart University, Bangkok 10900, Thailand.
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2
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Yiamsawat K, Gable KP, Chuawong P. Dissecting the Electronic Contribution to the Regioselectivity of the Larock Heteroannulation Reaction in the Oxidative Addition and Carbopalladation Steps. J Org Chem 2022; 87:1218-1229. [PMID: 34989564 DOI: 10.1021/acs.joc.1c02560] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Substituted 2-iodoaniline derivatives were prepared and utilized as reactants, along with asymmetric diarylacetylenes, to synthesize a series of 6-substituted-2,3-diarylindole derivatives via the Larock heteroannulation reaction. Electron-donating substituents on the 2-iodoaniline derivatives retarded the reaction, while electron-withdrawing substituents provided a complete conversion to the indole products. In addition, the electronic properties of the substituted 2-iodoaniline reactants displayed no influence toward regioselectivity. On the contrary, the electronic effect from unsymmetrical diarylacetylenes significantly influenced the regiochemical outcome of the reaction. Density functional theory calculations of the oxidative addition and carbopalladation steps revealed the electronic influences of the substituted 2-iodoaniline derivatives toward the overall rate of the reaction. In contrast, the electronic properties of the asymmetric diarylacetylene remained the critical product-determining factor of regioselectivity.
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Affiliation(s)
- Kanyapat Yiamsawat
- Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Special Research Unit for Advanced Magnetic Resonance (AMR), Kasetsart University, Bangkok 10900, Thailand
| | - Kevin P Gable
- Department of Chemistry, Oregon State University, 153 Gilbert Hall, Corvallis, Oregon 97331-4003, United States
| | - Pitak Chuawong
- Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Special Research Unit for Advanced Magnetic Resonance (AMR), Kasetsart University, Bangkok 10900, Thailand
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3
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Mousavifar L, Touaibia M, Roy R. Development of Mannopyranoside Therapeutics against Adherent-Invasive Escherichia coli Infections. Acc Chem Res 2018; 51:2937-2948. [PMID: 30289687 DOI: 10.1021/acs.accounts.8b00397] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Preventing bacterial adhesion to host cells is a provocative and alternative approach to traditional antibiotic treatments given the increasing microbial resistance. A brief overview of common antibiotic treatments is described in light of their respective resistance and remaining susceptibility. This strategy has been seriously considered in the context of adherent-invasive infections in Crohn's disease and urinary tract infections in particular. The adhesions of various pathogenic Escherichia coli strains to host cells are primarily mediated through carbohydrate-protein interactions involving bacterial organelles called fimbriae that can recognize specific glycoconjugate receptors on host cells. Of particular interest are the FimH and PapG fimbriae, which bind to mannosylated glycoproteins and glycolipids of the galabiose series, respectively. Therefore, blocking FimH- and PapG-mediated bacterial adhesion to uroepithelial cells by high-affinity carbohydrate antagonists constitutes a challenging therapeutic target of high interest. This is of particular interest since bacterial adhesion to host cells is a parameter unlikely to be the subject of bacterial mutations without affecting the carbohydrate ligand binding interactions at the basis of the recognition and infection processes. To date, there have been several families of potent FimH antagonists that include natural O-linked as well as unnatural analogues of α-d-mannopyranosides. These observations led to a thorough understanding of the intimate binding site interactions that helped to reveal the so-called "tyrosine gate mechanism" at the origin of the strong necessary interactions with sugar-possessing hydrophobic aglycones. By modification of the aglycones of single monosaccharidic d-mannopyranosides, it was possible to replace the natural complex oligomannoside structure by simpler ones. An appealing and successful series of analogues have been disclosed, including nanomolecular architectures such as dendrimers, polymers, and liposomes. In addition, the data were compared to the above multivalent architectures and confirmed the possibility of working with small sugar candidates. This Account primarily concentrates on the most promising types of FimH inhibitors belonging to the family of α-C-linked mannopyranosides. However, one of the drawbacks associated with C-mannopyranosides has been that they were believed to be in the inverted chair conformation, which is obviously not recognized by the E. coli FimH. To decipher this situation, various synthetic approaches, conformational aspects, and restrictions are discussed using molecular modeling, high-field NMR spectroscopy, and X-ray analysis. These combined techniques pointed to the fact that several α-C-linked mannopyranosides do exist in the required 4C1 chair conformation. Ultimately, recent findings in this growing field of interest culminated in the identification of drug candidates that have reached clinical phase I.
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Affiliation(s)
- Leila Mousavifar
- Department of Chemistry, Université du Québec à Montréal, P.O. Box 8888, Succ. Centre-Ville, Montréal, Québec H3C 3P8, Canada
- INRS-Institut Armand-Frappier, Université du Québec, 531 boul. des Prairies, Laval, Québec H7V 1B7, Canada
| | - Mohamed Touaibia
- Department of Chemistry and Biochemistry, Université de Moncton, Moncton, New Brunswick E1A 3E9, Canada
| | - René Roy
- Department of Chemistry, Université du Québec à Montréal, P.O. Box 8888, Succ. Centre-Ville, Montréal, Québec H3C 3P8, Canada
- INRS-Institut Armand-Frappier, Université du Québec, 531 boul. des Prairies, Laval, Québec H7V 1B7, Canada
- Glycovax Pharma Inc., 424 Guy, Suite 202, Montréal, Québec H3J 1S6, Canada
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Bokor É, Kun S, Goyard D, Tóth M, Praly JP, Vidal S, Somsák L. C-Glycopyranosyl Arenes and Hetarenes: Synthetic Methods and Bioactivity Focused on Antidiabetic Potential. Chem Rev 2017; 117:1687-1764. [PMID: 28121130 DOI: 10.1021/acs.chemrev.6b00475] [Citation(s) in RCA: 133] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
This Review summarizes close to 500 primary publications and surveys published since 2000 about the syntheses and diverse bioactivities of C-glycopyranosyl (het)arenes. A classification of the preparative routes to these synthetic targets according to methodologies and compound categories is provided. Several of these compounds, regardless of their natural or synthetic origin, display antidiabetic properties due to enzyme inhibition (glycogen phosphorylase, protein tyrosine phosphatase 1B) or by inhibiting renal sodium-dependent glucose cotransporter 2 (SGLT2). The latter class of synthetic inhibitors, very recently approved as antihyperglycemic drugs, opens new perspectives in the pharmacological treatment of type 2 diabetes. Various compounds with the C-glycopyranosyl (het)arene motif were subjected to biological studies displaying among others antioxidant, antiviral, antibiotic, antiadhesive, cytotoxic, and glycoenzyme inhibitory effects.
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Affiliation(s)
- Éva Bokor
- Department of Organic Chemistry, University of Debrecen , P.O. Box 400, Debrecen H-4002, Hungary
| | - Sándor Kun
- Department of Organic Chemistry, University of Debrecen , P.O. Box 400, Debrecen H-4002, Hungary
| | - David Goyard
- Institut de Chimie et Biochimie Moléculaires et Supramoléculaires, Laboratoire de Chimie Organique 2 - Glycochimie, UMR 5246, Université Claude Bernard Lyon 1 and CNRS , 43 Boulevard du 11 Novembre 1918, Villeurbanne F-69622, France
| | - Marietta Tóth
- Department of Organic Chemistry, University of Debrecen , P.O. Box 400, Debrecen H-4002, Hungary
| | - Jean-Pierre Praly
- Institut de Chimie et Biochimie Moléculaires et Supramoléculaires, Laboratoire de Chimie Organique 2 - Glycochimie, UMR 5246, Université Claude Bernard Lyon 1 and CNRS , 43 Boulevard du 11 Novembre 1918, Villeurbanne F-69622, France
| | - Sébastien Vidal
- Institut de Chimie et Biochimie Moléculaires et Supramoléculaires, Laboratoire de Chimie Organique 2 - Glycochimie, UMR 5246, Université Claude Bernard Lyon 1 and CNRS , 43 Boulevard du 11 Novembre 1918, Villeurbanne F-69622, France
| | - László Somsák
- Department of Organic Chemistry, University of Debrecen , P.O. Box 400, Debrecen H-4002, Hungary
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Herraiz-Cobo J, Albericio F, Álvarez M. The Larock Reaction in the Synthesis of Heterocyclic Compounds. ADVANCES IN HETEROCYCLIC CHEMISTRY 2015. [DOI: 10.1016/bs.aihch.2015.04.003] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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6
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Phetrak N, Rukkijakan T, Sirijaraensre J, Prabpai S, Kongsaeree P, Klinchan C, Chuawong P. Regioselectivity of Larock Heteroannulation: A Contribution from Electronic Properties of Diarylacetylenes. J Org Chem 2013; 78:12703-9. [DOI: 10.1021/jo402304s] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
| | | | | | - Samran Prabpai
- Department
of Chemistry and Center for Excellence in Protein Structure and Function,
Faculty of Science, Mahidol University, Bangkok 10400, Thailand
| | - Palangpon Kongsaeree
- Department
of Chemistry and Center for Excellence in Protein Structure and Function,
Faculty of Science, Mahidol University, Bangkok 10400, Thailand
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7
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Wang C, Sperry J. Total syntheses of the dipyrrolobenzoquinone (+)-terreusinone enabled by an evaluation of 4-methylpent-1-yn-3-ols in the Larock indole synthesis. Tetrahedron 2013. [DOI: 10.1016/j.tet.2013.04.025] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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8
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Wang C, Sperry J. Total Synthesis of the Photoprotecting Dipyrrolobenzoquinone (+)-Terreusinone. Org Lett 2011; 13:6444-7. [DOI: 10.1021/ol2027398] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Christy Wang
- School of Chemical Sciences, University of Auckland, 23 Symonds Street, Auckland, New Zealand
| | - Jonathan Sperry
- School of Chemical Sciences, University of Auckland, 23 Symonds Street, Auckland, New Zealand
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Cacchi S, Fabrizi G. Update 1 of: Synthesis and Functionalization of Indoles Through Palladium-Catalyzed Reactions. Chem Rev 2011; 111:PR215-83. [PMID: 21557620 DOI: 10.1021/cr100403z] [Citation(s) in RCA: 604] [Impact Index Per Article: 46.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Sandro Cacchi
- Dipartimento di Chimica e Technologie del Farmaco,
Sapienza, Università di Roma, P.le A. Moro 5, 00185 Roma, Italy
- This is a Chemical Reviews Perennial Review. The root paper of this title was
published in Chem. Rev.2005, 105 (7), 2873−2920, DOI: 10.1021/cr040639b; Published
(Web) July 13, 2005. Updates to the text appear in red type
| | - Giancarlo Fabrizi
- Dipartimento di Chimica e Technologie del Farmaco,
Sapienza, Università di Roma, P.le A. Moro 5, 00185 Roma, Italy
- This is a Chemical Reviews Perennial Review. The root paper of this title was
published in Chem. Rev.2005, 105 (7), 2873−2920, DOI: 10.1021/cr040639b; Published
(Web) July 13, 2005. Updates to the text appear in red type
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Trzupek JD, Li C, Chan C, Crowley BM, Heimann AC, Danishefsky SJ. Lessons from the Total Synthesis of (±) Phalarine: Insights Into the Mechanism of the Pictet-Spengler Reaction. ACTA ACUST UNITED AC 2010; 82:1735-1748. [PMID: 20711493 DOI: 10.1351/pac-con-09-11-14] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The furanobisindole alkaloid, phalarine, possesses a unique structural framework within the alkaloid family of natural products. Our laboratory recently disclosed the racemic total synthesis of phalarine, featuring an efficient azaspiroindolenine rearrangement; this achievement is revisited in detail. Upon completion of the first-generation total synthesis, we explored some interesting mechanism-level issues with regard to the key azaspiroindolenine rearrangement. These investigations provided valuable insights into the mechanism of racemization during the azaspiroindolenine rearrangement en route to synthetic phalarine. In addition, in the course of these studies, we demonstrated the Pictet-Spengler capture reaction for C(2)-aryl indoles, and successfully isolated the elusive azaspiroindolenine intermediate of the Pictet-Spengler reaction. Key insights into the remarkably subtle stereoelectronics that govern this rearrangement for C(2)-arylated indoles are discussed.
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Affiliation(s)
- John D Trzupek
- Laboratory for Bioorganic Chemistry, Sloan-Kettering Institute for Cancer Research, 1275 York Avenue, New York, New York 10065
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11
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Aldhoun M, Massi A, Dondoni A. Click azide-nitrile cycloaddition as a new ligation tool for the synthesis of tetrazole-tethered C-glycosyl alpha-amino acids. J Org Chem 2009; 73:9565-75. [PMID: 18847242 DOI: 10.1021/jo801670k] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Glycoproteins play a key role in a multitude of biological events in living organisms. Hence, neoglycopeptides obtained from unnatural C-glycosyl alpha-amino acids can be used as synthetic probes in studies aiming at clarifying the role of the carbohydrate domain in glycoprotein biological activity. A new class of C-glycosyl alpha-amino acids featuring a nitrogenated heterocycle ring holding the carbohydrate and glycinyl moiety was designed in our laboratory. Having previously prepared isoxazole-, 1,2,3-triazole-, and pyridine-tethered compounds, the family has now been enlarged by a group of newcomers represented by tetrazole derivatives. Two sets of compounds have been prepared, one being constituted of C-galactosyl and C-ribosyl O-tetrazolyl serines while the other contains S-tetrazolyl cysteine derivatives. In both cases, the synthetic scheme involved a two-step route, the first one being the thermal cycloaddition of a sugar azide with p-toluensulfonyl cyanide (TsCN) to give a 1-substituted 5-sulfonyl tetrazole and the second the replacement of the tosyl group with a serine or cysteine residue. For the high efficiency and operational simplicity, the azide-TsCN cycloaddition appears to be a true click process. Finally, one of the amino acids prepared was incorporated into a tripeptide.
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Affiliation(s)
- Mohammad Aldhoun
- Dipartimento di Chimica, Laboratorio di Chimica Organica, Università di Ferrara, Via L. Borsari 46, I-44100 Ferrara, Italy
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12
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Denmark SE, Baird JD. Preparation of 2,3-Disubstituted Indoles by Sequential Larock Heteroannulation and Silicon-Based Cross-Coupling Reactions. Tetrahedron 2009; 65:3120-3129. [PMID: 19784400 DOI: 10.1016/j.tet.2008.10.043] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
A simple and convergent synthesis of 2,3-disubstituted indoles has been developed using a sequential Larock indole synthesis and silicon-based, cross-coupling reaction. Substituted 2-iodoanilines reacted with an alkynyldimethylsilyl tert-butyl ether to afford indole-2-silanols under the Larock heteroannulation conditions after hydrolysis. The corresponding sodium 2-indolylsilanolate salts successfully engaged in cross-coupling with aryl bromides and chlorides to afford multi-substituted indoles. The development of an alkynyldimethylsilyl tert-butyl ether as a masked silanol equivalent enabled a smooth heteroannulation process and the identification of a suitable catalyst/ligand combination provided for a facile cross-coupling reaction.
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Affiliation(s)
- Scott E Denmark
- Roger Adams Laboratory, Department of Chemistry, University of Illinois Urbana, IL 61801
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13
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Barghash RF, Massi A, Dondoni A. Synthesis of thiourea-tethered C-glycosyl amino acids via isothiocyanate–amine coupling. Org Biomol Chem 2009; 7:3319-30. [DOI: 10.1039/b908156a] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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Dondoni A, Massi A, Sabbatini S. Multiple Component Approaches to C-Glycosyl β-Amino Acids by Complementary One-Pot Mannich-Type and Reformatsky-Type Reactions. Chemistry 2005; 11:7110-25. [PMID: 16224807 DOI: 10.1002/chem.200500823] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The development of new methods for the preparation of C-glycosyl beta-amino acid libraries with chemical and stereochemical diversity levels was investigated and the results are described herein. Two complementary one-pot three-component Mannich-type and Reformatsky-type synthetic strategies have been developed for the construction of chiral 3-amino propanoate fragments (eventually bis-substituted at C-2) directly linked to the anomeric carbon of pyranose and furanose residues. Both methods involved as the initial step the coupling of a sugar aldehyde to p-methoxybenzylamine but differed in the nucleophile (a d(2) synthon equivalent) which was successively added: a ketene silyl acetal (Mannich route) or a bromozinc enolate (Reformatsky route). Individual C-glycosyl beta-amino esters were isolated as single 3R diastereoisomers in fair to excellent yield (60-90%) and their structure assigned by NMR spectroscopy (Riguera protocol) supported by X-ray crystallography. A tentative explanation of the observed stereochemical outcome based on transition-state models is provided. A preliminary study on the synthesis of alpha,alpha-difluoro C-glycosyl beta-amino acids via a more traditional Reformatsky route is also reported.
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Affiliation(s)
- Alessandro Dondoni
- Laboratorio di Chimica Organica, Dipartimento di Chimica, Università di Ferrara, Via L. Borsari 46, 44100 Ferrara, Italy.
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Cacchi S, Fabrizi G. Synthesis and functionalization of indoles through palladium-catalyzed reactions. Chem Rev 2005; 105:2873-920. [PMID: 16011327 DOI: 10.1021/cr040639b] [Citation(s) in RCA: 1530] [Impact Index Per Article: 80.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Sandro Cacchi
- Dipartimento di Studi di Chimica e Tecnologia delle Sostanze Biologicamente Attive, Università degli Studi La Sapienza, P.le A. Moro 5, 00185 Roma, Italy.
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Nishikawa T, Koide Y, Kajii S, Wada K, Ishikawa M, Isobe M. Stereocontrolled syntheses of α-C-mannosyltryptophan and its analogues. Org Biomol Chem 2005; 3:687-700. [PMID: 15703809 DOI: 10.1039/b414905j] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The total synthesis of alpha-C-mannosyltryptophan (C-Man-Trp), a naturally occurring C-glycosylamino acid, was achieved from a commercially available alpha-methyl-D-mannoside in 10 steps including the following key steps: the C-glycosidation of a mannose derivative with a stannylacetylene, Castro indole synthesis, and Sc(ClO4)3-promoted coupling with L-serine-derived aziridine carboxylate. The glucose- and galactose-analogues of C-Man-Trp were also synthesized in a similar manner. Conformational analyses of the synthesized C-glycosyltryptophan and its synthetic intermediate are briefly discussed.
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Affiliation(s)
- Toshio Nishikawa
- Laboratory of Organic Chemistry, Graduate School of Bioagricultural Sciences, Nagoya University, Chikusa, Nagoya 464-8601, Japan.
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Nishikawa T, Kajii S, Sato C, Yasukawa Z, Kitajima K, Isobe M. α-C-Mannosyltryptophan is not recognized by conventional mannose-binding lectins. Bioorg Med Chem 2004; 12:2343-8. [PMID: 15080931 DOI: 10.1016/j.bmc.2004.02.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2004] [Revised: 02/04/2004] [Accepted: 02/04/2004] [Indexed: 10/26/2022]
Abstract
Alpha-C-mannosyltryptophan (C-Man-Trp) is a novel, naturally occurring C-linked carbohydrate-protein linkage first found in 1994 from human ribonuclease 2. Since then, a number of C-Man-Trp residue have been found from several important proteins such as interleukin 12 beta, components of complement system, thrombospondin-1, and erythropoietin receptor, however, the biological functions have remained unknown even though its biosynthetic pathway has been revealed. In order to find a clue as to the biological functions, we examined the affinity of C-Man-Trp with conventional mannose lectin such as concanavarin A (Con A) and mannose-binding lectin (MBL). The affinity of C-Man-Trp with Con A, a typical mannose-binding lectin from plant was examined using a Con A-Sepharose column. Unlike p-nitrophenyl-alpha-O-Man, C-Man-Trp was not retained on the column. MBL-C, a major mannose-binding lectin purified from mouse serum, did not bind with N-biotinylated C-Man-Trp, judging from ELISA based assay. These results imply that C-Man-Trp may be recognized with the other specific proteins associated with its unknown biological functions.
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Affiliation(s)
- Toshio Nishikawa
- Laboratory of Organic Chemistry, Graduate School of Bioagricultural Sciences, Nagoya University, Chikusa, Nagoya 464-8601, Japan.
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