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Wang Y, Opsomer T, de Jong F, Verhaeghe D, Mulier M, Van Meervelt L, Van der Auweraer M, Dehaen W. Palladium-Catalyzed Arylations towards 3,6-Diaryl-1,3a,6a-triazapentalenes and Evaluation of Their Fluorescence Properties. Molecules 2024; 29:2229. [PMID: 38792091 PMCID: PMC11123795 DOI: 10.3390/molecules29102229] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2024] [Revised: 05/01/2024] [Accepted: 05/02/2024] [Indexed: 05/26/2024] Open
Abstract
Methyl 4-(1,3a,6a-triazapentalen-3-yl)benzoate (TAP1) shows interesting properties as a small molecule fluorophore. In the search for post-functionalization methods, palladium-catalyzed arylation reactions were demonstrated. Direct CH arylation reactions of TAP1 with various aryl halides resulted in 3,6-diaryltriazapentalenes TAP4, although mostly in poor yields. Bromination of TAP1 followed by Suzuki coupling, on the other hand, requires a more delicate procedure, but gave arylated products with the same regiochemistry (TAP4) in moderate to good yields. The structure of 6-phenyltriazapentalene TAP4a was confirmed by crystallographic analysis. In addition, the effect of the C6 arylation on the fluorescent properties of 3-aryl-1,3a,6a-triazapentalenes was studied in dichloromethane at room temperature and in 2-methyltetrahydrofuran at 77 K, while the photophysical properties of two saponified derivatives were measured in acetonitrile.
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Affiliation(s)
- Yingchun Wang
- Sustainable Chemistry for Metals and Molecules, Department of Chemistry, KU Leuven, Celestijnenlaan 200F, 3001 Leuven, Belgium
| | - Tomas Opsomer
- Sustainable Chemistry for Metals and Molecules, Department of Chemistry, KU Leuven, Celestijnenlaan 200F, 3001 Leuven, Belgium
| | - Flip de Jong
- Molecular Imaging and Photonics, Department of Chemistry, KU Leuven, Celestijnenlaan 200F, 3001 Leuven, Belgium; (F.d.J.); (M.V.d.A.)
| | - Davy Verhaeghe
- Molecular Imaging and Photonics, Department of Chemistry, KU Leuven, Celestijnenlaan 200F, 3001 Leuven, Belgium; (F.d.J.); (M.V.d.A.)
| | - Maarten Mulier
- Sustainable Chemistry for Metals and Molecules, Department of Chemistry, KU Leuven, Celestijnenlaan 200F, 3001 Leuven, Belgium
| | - Luc Van Meervelt
- Biochemistry, Molecular and Structural Biology, Department of Chemistry, KU Leuven, Celestijnenlaan 200F, 3001 Leuven, Belgium;
| | - Mark Van der Auweraer
- Molecular Imaging and Photonics, Department of Chemistry, KU Leuven, Celestijnenlaan 200F, 3001 Leuven, Belgium; (F.d.J.); (M.V.d.A.)
| | - Wim Dehaen
- Sustainable Chemistry for Metals and Molecules, Department of Chemistry, KU Leuven, Celestijnenlaan 200F, 3001 Leuven, Belgium
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2
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Wang R, Stevaert A, Truong TN, Li Q, Krasniqi B, Van Loy B, Voet A, Naesens L, Dehaen W. Exploration of 1,2,3-triazolo fused triterpenoids as inhibitors of human coronavirus 229E targeting the viral nsp15 protein. Arch Pharm (Weinheim) 2024; 357:e2300442. [PMID: 37840345 DOI: 10.1002/ardp.202300442] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2023] [Revised: 09/20/2023] [Accepted: 09/20/2023] [Indexed: 10/17/2023]
Abstract
The coronavirus disease-19 (COVID-19) pandemic has raised major interest in innovative drug concepts to suppress human coronavirus (HCoV) infections. We previously reported on a class of 1,2,3-triazolo fused betulonic acid derivatives causing strong inhibition of HCoV-229E replication via the viral nsp15 protein, which is proposedly related to compound binding at an intermonomer interface in hexameric nsp15. In the present study, we further explored the structure-activity relationship (SAR), by varying the substituent at the 1,2,3-triazolo ring as well as the triterpenoid skeleton. The 1,2,3-triazolo fused triterpenoids were synthesized by a multicomponent triazolization reaction, which has been developed in-house. Several analogs possessing a betulin, oleanolic acid, or ursolic acid core displayed favorable activity and selectivity (EC50 values for HCoV-229E: 1.6-3.5 μM), but neither of them proved as effective as the lead compound containing betulonic acid. The 18β-glycyrrhetinic acid-containing analogs had low selectivity. The antiviral findings were rationalized by in silico docking in the available structure of the HCoV-229E nsp15 protein. The new SAR insights will aid the further development of these 1,2,3-triazolo fused triterpenoid compounds as a unique type of coronavirus inhibitors.
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Affiliation(s)
- Rui Wang
- Department of Chemistry, Sustainable Chemistry for Metals and Molecules, KU Leuven, Leuven, Belgium
| | - Annelies Stevaert
- Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical Research, KU Leuven, Leuven, Belgium
| | - Tien Nguyen Truong
- Department of Chemistry, Biochemistry, Molecular and Structural Biology, KU Leuven, Leuven, Belgium
| | - Qifei Li
- Department of Chemistry, Sustainable Chemistry for Metals and Molecules, KU Leuven, Leuven, Belgium
| | - Besir Krasniqi
- Department of Chemistry, Sustainable Chemistry for Metals and Molecules, KU Leuven, Leuven, Belgium
| | - Benjamin Van Loy
- Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical Research, KU Leuven, Leuven, Belgium
| | - Arnout Voet
- Department of Chemistry, Biochemistry, Molecular and Structural Biology, KU Leuven, Leuven, Belgium
| | - Lieve Naesens
- Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical Research, KU Leuven, Leuven, Belgium
| | - Wim Dehaen
- Department of Chemistry, Sustainable Chemistry for Metals and Molecules, KU Leuven, Leuven, Belgium
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3
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Motornov V, Beier P. NH-1,2,3-triazoles as versatile building blocks in denitrogenative transformations. RSC Adv 2023; 13:34646-34651. [PMID: 38024996 PMCID: PMC10680141 DOI: 10.1039/d3ra06045d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Accepted: 11/22/2023] [Indexed: 12/01/2023] Open
Abstract
The utilization of NH-1,2,3-triazoles as easily accessible building blocks in denitrogenative ring cleavage transformations with electrophiles to provide multifunctionalized nitrogen heterocycles and N-alkenyl compounds is reviewed. Leveraging the ready availability of NH-1,2,3-triazoles, these processes provide a convenient route to a range of pharmaceutically relevant heterocyclic cores and N-alkenyl compounds. The synthetic usefulness of in situ acylated NH-1,2,3-triazoles as viable alternatives to widely explored N-sulfonyl-1,2,3-triazoles in ring cleavage processes is highlighted.
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Affiliation(s)
- Vladimir Motornov
- Institute of Orgranic Chemistry and Biochemistry, Academy of Sciences Flemingovo nám. 2 160 00 Prague 6 Czech Republic
| | - Petr Beier
- Institute of Orgranic Chemistry and Biochemistry, Academy of Sciences Flemingovo nám. 2 160 00 Prague 6 Czech Republic
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4
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Wang R, Krasniqi B, Li Y, Dehaen W. Triphenylphosphonium-linked derivative of allobetulin: preparation, anticancer properties and their mechanism of inhibiting SGC-7901 cells proliferation. Bioorg Chem 2022; 126:105853. [DOI: 10.1016/j.bioorg.2022.105853] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 04/15/2022] [Accepted: 05/03/2022] [Indexed: 11/27/2022]
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1-(4-Nitrophenyl)-1H-1,2,3-Triazole-4-carbaldehyde: Scalable Synthesis and Its Use in the Preparation of 1-Alkyl-4-Formyl-1,2,3-triazoles. ORGANICS 2021. [DOI: 10.3390/org2040024] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
1,2,3-Triazole-4-carbaldehydes are useful synthetic intermediates which may play an important role in the discovery of novel applications of the 1,2,3-triazole moiety. In this work, a one-step multigram scale synthesis of 4-formyl-1-(4-nitrophenyl)-1H-1,2,3-triazole (FNPT) as a preferred reagent for the synthesis of 1-alkyl-4-formyltriazoles is described, making use of the commercially available 3-dimethylaminoacrolein and 4-nitrophenyl azide. Next, the earlier reported reaction of FNPT with alkylamines is further explored, and for hexylamine, the one-pot sequential cycloaddition and Cornforth rearrangement is demonstrated. In addition, a useful protocol for the in situ diazotization of 4-nitroaniline is provided. This facilitated the complete hydrolysis of rearranged 4-iminomethyl-1,2,3-triazoles and allowed for the recycling of 4-nitrophenyl azide.
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6
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Synthesis and Anti-HIV Activity of a Novel Series of Isoquinoline-Based CXCR4 Antagonists. Molecules 2021; 26:molecules26206297. [PMID: 34684878 PMCID: PMC8539250 DOI: 10.3390/molecules26206297] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Revised: 10/13/2021] [Accepted: 10/14/2021] [Indexed: 11/26/2022] Open
Abstract
An expansion of the structure–activity relationship study of CXCR4 antagonists led to the synthesis of a series of isoquinolines, bearing a tetrahydroquinoline or a 3-methylpyridinyl moiety as head group. All compounds were investigated for CXCR4 affinity and antagonism in competition binding and calcium mobilization assays, respectively. In addition, the anti-HIV activity of all analogues was determined. All compounds showed excellent activity, with compound 24c being the most promising one, since it displayed consistently low nanomolar activity in the various assays.
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Horsten T, de Jong F, Theunissen D, Van der Auweraer M, Dehaen W. Synthesis and Spectroscopic Properties of 1,2,3-Triazole BOPAHY Dyes and Their Water-Soluble Triazolium Salts. J Org Chem 2021; 86:13774-13782. [PMID: 34516732 DOI: 10.1021/acs.joc.1c01459] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Water-soluble BOPAHY fluorophores have not yet been reported. The potential of 1,2,3-triazolium salts for the formation of water-soluble chromophores is explored. 1,2,3-Triazole-substituted pyrroles were synthesized in a metal-free pathway and alkylated to obtain water-soluble 1,2,3-triazolium BOPAHY dyes. High fluorescence quantum yields were observed for triazole-bridged BOPAHY dyes in DCM and moderate fluorescence quantum yields for 1,2,3-triazolium-bridged BOPAHY chromophores in DCM and water. The fluorescence of the freely rotatable 1,2,3-triazolium-linked BOPAHYs is partially quenched in water.
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Affiliation(s)
- Tomas Horsten
- Molecular Design and Synthesis, Department of Chemistry, KU Leuven, Celestijnenlaan 200F, 3001 Leuven, Belgium
| | - Flip de Jong
- Molecular Imaging and Photonics, Department of Chemistry, KU Leuven, Celestijnenlaan 200F, 3001 Leuven, Belgium
| | - Dries Theunissen
- Molecular Design and Synthesis, Department of Chemistry, KU Leuven, Celestijnenlaan 200F, 3001 Leuven, Belgium
| | - Mark Van der Auweraer
- Molecular Imaging and Photonics, Department of Chemistry, KU Leuven, Celestijnenlaan 200F, 3001 Leuven, Belgium
| | - Wim Dehaen
- Molecular Design and Synthesis, Department of Chemistry, KU Leuven, Celestijnenlaan 200F, 3001 Leuven, Belgium
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8
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Li JZ, Zhang WK, Ge GP, Zheng H, Wei WT. Recent progress in the radical α-C(sp 3)-H functionalization of ketones. Org Biomol Chem 2021; 19:7333-7347. [PMID: 34612358 DOI: 10.1039/d1ob01408k] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The direct use structurally simple ketones as α-ketone radical sources for α-C(sp3)-H functionalization is a sustainable and powerful approach for constructing complex and multifunctional chemical scaffolds with diverse applications. The reactions of α-ketone radicals with alkenes, alkynes, enynes, imides, and imidazo[1,2-a]pyridines have broadened the structural diversity and complexity of ketones. Through chosen illustrative examples, we outline the recent progress in the development of methods that enable the radical α-C(sp3)-H functionalization of ketones, with an emphasis on radical initiation systems and possible mechanisms of the transformations. The application of these strategies is illustrated by the synthesis of several biologically active molecules and drug molecules. Further subdivision is based on substrate type and reaction type.
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Affiliation(s)
- Jiao-Zhe Li
- Key Laboratory of Advanced Mass Spectrometry and Molecular Analysis of Zhejiang Province, State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, School of Materials Science and Chemical Engineering, Ningbo University, Ningbo, Zhejiang 315211, China.
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Oxidative cyclization of 5-aryl-1-benzyl-1,2,3-triazoles bearing electron-rich aromatic groups: ortho/ortho and ortho/ipso coupling. Chem Heterocycl Compd (N Y) 2021. [DOI: 10.1007/s10593-021-02985-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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10
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Wang R, Li Y, Hu H, Persoons L, Daelemans D, De Jonghe S, Luyten W, Krasniqi B, Dehaen W. Antibacterial and antitumoral properties of 1,2,3-triazolo fused triterpenes and their mechanism of inhibiting the proliferation of HL-60 cells. Eur J Med Chem 2021; 224:113727. [PMID: 34352711 DOI: 10.1016/j.ejmech.2021.113727] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2021] [Revised: 07/19/2021] [Accepted: 07/27/2021] [Indexed: 01/04/2023]
Abstract
Antimicrobial resistance and cancer are two important problems affecting human health. Actively developing novel antibiotics and anticancer medicines is a priority. Natural pentacyclic triterpenoids have attracted wide attention due to their significant biological activities. In this study, a series of 1,2,3-triazolo fused triterpenoids (betulin, oleanolic acid and ursolic acid) were functionalized on the A-ring by an in-house developed multi-component triazolization reaction. The compounds were investigated for antitumoral activity in twelve cancer cell lines and were also tested for antibacterial activity against four bacteria. In terms of anticancer effects, compounds 5b-f and 8a-d displayed strong cytotoxic activity in pancreatic adenocarcinoma (Capan-1), chronic myeloid leukemia (Hap-1), acute myeloid leukemia (HL-60), acute lymphoblastic leukemia (Jurkat) and non-Hodgkin lymphoma (Rec-1) cell lines. Among them, compound 5f exhibited the most potent antiproliferative effect on HL-60 cells. Further pharmacological research confirmed that compound 5f caused mitochondrial dysfunction and arrested the cell cycle in the G0/G1 phase to induce apoptosis of HL-60 cells. In addition, compound 5f also induced autophagy to inhibit the proliferation of HL-60 cells. Antibacterial screening revealed that compounds 2a-g and 5a-d showed modest activity against Gram-negative bacteria (Escherichia coli and Salmonella enterica subsp. enterica) with especially compounds 2c and 2d being potent inhibitors of Salmonella enterica subsp. enterica growth. Because of their promising anticancer and antibacterial activity, this series of compounds deserve further study.
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Affiliation(s)
- Rui Wang
- Molecular Design and Synthesis, Department of Chemistry, KU Leuven, Celestijnenlaan 200F, B-3001, Leuven, Belgium
| | - Yang Li
- Zhong Yuan Academy of Biological Medicine, Liaocheng People's Hospital, Liaocheng, 252000, PR China
| | - Haibo Hu
- Department of Biology, Animal Physiology and Neurobiology Section, KU Leuven, Naamsestraat 59, Box 2465, B-3000, Leuven, Belgium
| | - Leentje Persoons
- KU Leuven, Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical Research, Laboratory of Virology and Chemotherapy, Herestraat 49 - Box 1043, B-3000, Leuven, Belgium
| | - Dirk Daelemans
- KU Leuven, Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical Research, Laboratory of Virology and Chemotherapy, Herestraat 49 - Box 1043, B-3000, Leuven, Belgium
| | - Steven De Jonghe
- KU Leuven, Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical Research, Laboratory of Virology and Chemotherapy, Herestraat 49 - Box 1043, B-3000, Leuven, Belgium
| | - Walter Luyten
- Department of Biology, Animal Physiology and Neurobiology Section, KU Leuven, Naamsestraat 59, Box 2465, B-3000, Leuven, Belgium
| | - Besir Krasniqi
- Molecular Design and Synthesis, Department of Chemistry, KU Leuven, Celestijnenlaan 200F, B-3001, Leuven, Belgium
| | - Wim Dehaen
- Molecular Design and Synthesis, Department of Chemistry, KU Leuven, Celestijnenlaan 200F, B-3001, Leuven, Belgium.
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Horsten T, Dehaen W. 4,5,6,7-Tetrahydroindol-4-Ones as a Valuable Starting Point for the Synthesis of Polyheterocyclic Structures. Molecules 2021; 26:4596. [PMID: 34361747 PMCID: PMC8348459 DOI: 10.3390/molecules26154596] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Revised: 07/26/2021] [Accepted: 07/27/2021] [Indexed: 11/17/2022] Open
Abstract
This review focuses on the synthesis of polyheterocyclic structures with a variety of medicinal and optoelectronic applications, starting from readily available 4,5,6,7-tetrahydroindol-4-one analogs. First, routes toward the 4,5,6,7-tetrahydroindol-4-one starting materials are summarized, followed by synthetic pathways towards polyheterocyclic structures which are categorized based on the size and attachment point of the newly formed (hetero)cyclic ring.
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Affiliation(s)
| | - Wim Dehaen
- Molecular Design and Synthesis, Department of Chemistry, KU Leuven, Celestijnenlaan 200F, B-3001 Leuven, Belgium;
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12
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Vroemans R, Ribone SR, Thomas J, Van Meervelt L, Ollevier T, Dehaen W. Synthesis of homochiral sulfanyl- and sulfoxide-substituted naphthyltriazoles and study of the conformational stability. Org Biomol Chem 2021; 19:6521-6526. [PMID: 34254109 DOI: 10.1039/d1ob00784j] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The preparation of a series of novel homochiral atropisomeric sulfanyl- and sulfoxide-substituted naphthyltriazoles is described. The triazolization methodology used presents a new way towards novel and highly stable 1,2,3-triazole-based atropisomers, and introduces a new and complementary synthetic pathway towards 4-sulfanyl substituted 1,2,3-triazoles. Starting from sulfanyl-substituted naphthyl ketones, enantiopure amines, and 4-nitrophenyl azide, a collection of 16 sulfanyl-substituted naphthyltriazoles were obtained via the triazolization reaction in which the homochiral diastereomers are readily isolated. Subsequent monooxidation results in the preparation of several sulfoxide-substituted naphthyltriazoles. The absolute configuration of a set of diastereomeric sulfanyl- and sulfoxide-appended naphthyltriazoles was deduced via X-ray crystallography. Furthermore, the conformational stability of the atropisomers was determined experimentally, and further confirmed and analyzed with the aid of computational DFT calculations.
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Affiliation(s)
- Robby Vroemans
- Molecular Design and Synthesis, Department of Chemistry, KU Leuven, Celestijnenlaan 200F, B-3001 Leuven, Belgium.
| | - Sergio R Ribone
- Unidad de Investigación y Desarrollo en Tecnología Farmacéutica (UNITEFA, CONICET), Dpto. Ciencias Farmacéuticas, Fac. Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba X5000HUA, Argentina
| | - Joice Thomas
- Molecular Design and Synthesis, Department of Chemistry, KU Leuven, Celestijnenlaan 200F, B-3001 Leuven, Belgium.
| | - Luc Van Meervelt
- Biochemistry, Molecular and Structural Biology, Department of Chemistry, KU Leuven, Celestijnenlaan 200F, B-3001 Leuven, Belgium
| | - Thierry Ollevier
- Département de chimie, Pavillon Alexandre-Vachon, Université Laval, 1045 avenue de la Médecine, Québec, QC G1V 0A6, Canada
| | - Wim Dehaen
- Molecular Design and Synthesis, Department of Chemistry, KU Leuven, Celestijnenlaan 200F, B-3001 Leuven, Belgium.
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Opsomer T, Dehaen W. Metal-free syntheses of N-functionalized and NH-1,2,3-triazoles: an update on recent developments. Chem Commun (Camb) 2021; 57:1568-1590. [PMID: 33491711 DOI: 10.1039/d0cc06654k] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
An overview of the latest developments in the metal-free synthesis of non-benzo-fused N-functionalized and NH-1,2,3-triazoles is provided in this feature article. Synthetic studies that appeared from 2016 until August 2020 are organized according to a wide-ranging classification, comprising oxidative and eliminative azide-dipolarophile cycloadditions, diazo transfer reactions and N-tosylhydrazone-mediated syntheses. The newly developed methods constitute a significant contribution to the field of 1,2,3-triazole synthesis in terms of structural variation via either the exploration of novel reactions, or the exploitation of existing methodologies.
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Affiliation(s)
- Tomas Opsomer
- Molecular Design and Synthesis, Department of Chemistry, KU Leuven, Celestijnenlaan 200F, 3001 Heverlee, Belgium.
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