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Yoshimura A, Zhdankin VV. Recent Progress in Synthetic Applications of Hypervalent Iodine(III) Reagents. Chem Rev 2024. [PMID: 39269928 DOI: 10.1021/acs.chemrev.4c00303] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/15/2024]
Abstract
Hypervalent iodine(III) compounds have found wide application in modern organic chemistry as environmentally friendly reagents and catalysts. Hypervalent iodine reagents are commonly used in synthetically important halogenations, oxidations, aminations, heterocyclizations, and various oxidative functionalizations of organic substrates. Iodonium salts are important arylating reagents, while iodonium ylides and imides are excellent carbene and nitrene precursors. Various derivatives of benziodoxoles, such as azidobenziodoxoles, trifluoromethylbenziodoxoles, alkynylbenziodoxoles, and alkenylbenziodoxoles have found wide application as group transfer reagents in the presence of transition metal catalysts, under metal-free conditions, or using photocatalysts under photoirradiation conditions. Development of hypervalent iodine catalytic systems and discovery of highly enantioselective reactions using chiral hypervalent iodine compounds represent a particularly important recent achievement in the field of hypervalent iodine chemistry. Chemical transformations promoted by hypervalent iodine in many cases are unique and cannot be performed by using any other common, non-iodine-based reagent. This review covers literature published mainly in the last 7-8 years, between 2016 and 2024.
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Affiliation(s)
- Akira Yoshimura
- Faculty of Pharmaceutical Sciences, Aomori University, 2-3-1 Kobata, Aomori 030-0943, Japan
| | - Viktor V Zhdankin
- Department of Chemistry and Biochemistry, University of Minnesota Duluth, Duluth, Minnesota 55812, United States
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2
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Juárez-Ornelas KA, Solís-Hernández M, Navarro-Santos P, Jiménez-Halla JOC, Solorio-Alvarado CR. Divergent role of PIDA and PIFA in the AlX 3 (X = Cl, Br) halogenation of 2-naphthol: a mechanistic study. Beilstein J Org Chem 2024; 20:1580-1589. [PMID: 39076287 PMCID: PMC11285080 DOI: 10.3762/bjoc.20.141] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2024] [Accepted: 06/27/2024] [Indexed: 07/31/2024] Open
Abstract
The reaction mechanism for the chlorination and bromination of 2-naphthol with PIDA or PIFA and AlX3 (X = Cl, Br), previously reported by our group, was elucidated via quantum chemical calculations using density functional theory. The chlorination mechanism using PIFA and AlCl3 demonstrated a better experimental and theoretical yield compared to using PIDA. Additionally, the lowest-energy chlorinating species was characterized by an equilibrium of Cl-I(Ph)-OTFA-AlCl3 and [Cl-I(Ph)][OTFA-AlCl3], rather than PhICl2 being the active species. On the other hand, bromination using PIDA and AlBr3 was more efficient, wherein the intermediate Br-I(Ph)-OAc-AlBr3 was formed as active brominating species. Similarly, PhIBr2 was higher in energy than our proposed species. The reaction mechanisms are described in detail in this work and were found to be in excellent agreement with the experimental yield. These initial results confirmed that our proposed mechanism was energetically favored and therefore more plausible compared to halogenation via PhIX2.
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Affiliation(s)
- Kevin A Juárez-Ornelas
- Departamento de Química, División de Ciencias Naturales y Exactas, Universidad de Guanajuato, Campus Gto, Noria Alta S/N 36050, Guanajuato, México
| | - Manuel Solís-Hernández
- CONAHCYT - Instituto de Investigaciones Químico Biológicas, Universidad Michoacana de San Nicolás de Hidalgo, Avenida Francisco J. Múgica S/N 58030, Morelia, Michoacán, México
| | - Pedro Navarro-Santos
- CONAHCYT - Instituto de Investigaciones Químico Biológicas, Universidad Michoacana de San Nicolás de Hidalgo, Avenida Francisco J. Múgica S/N 58030, Morelia, Michoacán, México
| | - J Oscar C Jiménez-Halla
- Departamento de Química, División de Ciencias Naturales y Exactas, Universidad de Guanajuato, Campus Gto, Noria Alta S/N 36050, Guanajuato, México
| | - César R Solorio-Alvarado
- Departamento de Química, División de Ciencias Naturales y Exactas, Universidad de Guanajuato, Campus Gto, Noria Alta S/N 36050, Guanajuato, México
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3
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Jiang Y, Yao M, Feng J, Niu H, Qiao B, Li B, Wang B, Xiao W, Dong M, Yuan Y. Molecular Insights into Converting Hydroxide Adenosyltransferase into Halogenase. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2024; 72:12685-12695. [PMID: 38771136 DOI: 10.1021/acs.jafc.4c02581] [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: 05/22/2024]
Abstract
Halogenation plays a unique role in the design of agrochemicals. Enzymatic halogenation reactions have attracted great attention due to their excellent specificity and mild reaction conditions. S-adenosyl-l-methionine (SAM)-dependent halogenases mediate the nucleophilic attack of halide ions (X-) to SAM to produce 5'-XDA. However, only 11 SAM-dependent fluorinases and 3 chlorinases have been reported, highlighting the desire for additional halogenases. SAM-dependent hydroxide adenosyltransferase (HATase) has a similar reaction mechanism as halogenases but uses water as a substrate instead of halide ions. Here, we explored a HATase from the thermophile Thermotoga maritima MSB8 and transformed it into a halogenase. We identified a key dyad W8L/V71T for the halogenation reaction. We also obtained the best performing mutants for each halogenation reaction: M1, M2 and M4 for Cl-, Br- and I-, respectively. The M4 mutant retained the thermostability of HATase in the iodination reaction at 80 °C, which surpasses the natural halogenase SalL. QM/MM revealed that these mutants bind halide ions with more suitable angles for nucleophilic attack of C5' of SAM, thus conferring halogenation capabilities. Our work achieved the halide ion specificity of halogenases and generated thermostable halogenases for the first time, which provides new opportunities to expand the halogenase repertoire from hydroxylase.
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Affiliation(s)
- Yixun Jiang
- Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China
- Frontier Research Institute for Synthetic Biology, Tianjin University, Tianjin 300072, China
| | - Mingdong Yao
- Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China
- Frontier Research Institute for Synthetic Biology, Tianjin University, Tianjin 300072, China
| | - Jianqiang Feng
- State Key Laboratory of Physical Chemistry of Solid Surfaces and Fujian Provincial Key Laboratory of Theoretical and Computational Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - Haoran Niu
- Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China
| | - Bin Qiao
- Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China
| | - Bingzhi Li
- Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China
- Frontier Research Institute for Synthetic Biology, Tianjin University, Tianjin 300072, China
| | - Binju Wang
- State Key Laboratory of Physical Chemistry of Solid Surfaces and Fujian Provincial Key Laboratory of Theoretical and Computational Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - Wenhai Xiao
- Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China
- School of Life Sciences, Faculty of Medicine, Tianjin University, Tianjin 300072, China
- Frontier Research Institute for Synthetic Biology, Tianjin University, Tianjin 300072, China
- Georgia Tech Shenzhen Institute, Tianjin University, Shenzhen 518071, China
| | - Min Dong
- Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China
| | - Yingjin Yuan
- Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China
- Frontier Research Institute for Synthetic Biology, Tianjin University, Tianjin 300072, China
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4
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Chillal AS, Bhawale RT, Kshirsagar UA. Regioselective C(sp 2)-H halogenation of pyrazolo[1,5- a]pyrimidines facilitated by hypervalent iodine(iii) under aqueous and ambient conditions. RSC Adv 2024; 14:13095-13099. [PMID: 38655480 PMCID: PMC11036372 DOI: 10.1039/d4ra02090a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2024] [Accepted: 04/15/2024] [Indexed: 04/26/2024] Open
Abstract
An efficient and mild approach has been developed for the regio-selective direct C3 halogenation of pyrazolo[1,5-a]pyrimidines employing readily available potassium halide salts and a hypervalent iodine(iii) reagent at ambient temperature. The protocol is both practical and environmentally friendly, utilizing water as a green solvent, potassium halides as an inexpensive and bench stable halogen source and PIDA as a non-toxic reagent, enabling clean and efficient halogenation at room temperature. The procedure yields a range of C3 halogenated pyrazolo[1,5-a]pyrimidines in good to excellent yields. Mechanistic studies suggest the involvement of electrophilic substitution mechanism in the halogenation process.
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Affiliation(s)
- Abhinay S Chillal
- Department of Chemistry, Indian Institute of Technology Indore Khandwa Road Indore 453552 India
| | - Rajesh T Bhawale
- Department of Chemistry, Indian Institute of Technology Indore Khandwa Road Indore 453552 India
| | - Umesh A Kshirsagar
- Department of Chemistry, Indian Institute of Technology Indore Khandwa Road Indore 453552 India
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Cui HL. Recent advances in oxidative chlorination. Org Biomol Chem 2024; 22:1580-1601. [PMID: 38312070 DOI: 10.1039/d3ob02012f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2024]
Abstract
Considering the wide occurrence and extensive application of organic chlorides in many research fields, the development of easy, practical and green chlorination methodologies is much needed. In the oxidative chlorination strategy, active chlorinating species can be in situ formed by the interaction of easily accessible chlorides such as NaCl, HCl, KCl, CHCl3, etc. and suitable oxidants. Among the established chlorination approaches, this strategy is an attractive one as it features the use of readily available, cheap and safe inorganic or organic chlorides, good atom economy of chlorine, and multiple choices of oxidants. This review summarizes the representative methodologies in the field of oxidative chlorination, covering 2013 to 2023.
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Affiliation(s)
- Hai-Lei Cui
- Laboratory of Asymmetric Synthesis, College of Chemistry and Environmental Engineering, Chongqing University of Arts and Sciences, 319 Honghe Ave., Yongchuan, Chongqing, 402160, PR China.
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6
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Segura-Quezada LA, Hernández-Velázquez ED, Corrales-Escobosa AR, de León-Solis C, Solorio-Alvarado CR. Ningalins, Pyrrole-Bearing Metabolites Isolated from Didemnum spp. Synthesis and MDR-Reversion Activity in Cancer Therapy. Chem Biodivers 2024; 21:e202300883. [PMID: 38010267 DOI: 10.1002/cbdv.202300883] [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: 06/15/2023] [Revised: 11/22/2023] [Accepted: 11/24/2023] [Indexed: 11/29/2023]
Abstract
Multi-Drug Resistance (MDR) is one of the most frequent problems observed in the course of cancer chemotherapy. Cells under treatment, tend to develop survival mechanisms to drug-action thus generating drug-resistance. One of the most important mechanism to get it is the over expression of P-gp glycoprotein, which acts as an efflux-pump releasing the drug outside of the cancer cell. A strategy for a succesfull treatment consists in the co-administration of one compound that acts against P-gp and another which acts against the cell during chemotherapy. Ningalins are pyrrole-containing naturally occurring compounds isolated mainly from the marine tunicate Didemnum spp and also they are some of the top reversing agents in MDR treatment acting on P-gp. Considering the relevance displayed for some of these isolated alkaloids or their core as a drug for co-administration in cancer therapy, all the total synthesis described to date for the members of ningalins family are reviewed herein.
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Affiliation(s)
- Luis A Segura-Quezada
- Universidad de Guanajuato, Departamento de Química, División de Ciencias Naturales y Exactas, Campus Guanajuato., Noria Alta S/N, 36050, Guanajuato, Gto., México
| | - Edson D Hernández-Velázquez
- Universidad de Guanajuato, Departamento de Química, División de Ciencias Naturales y Exactas, Campus Guanajuato., Noria Alta S/N, 36050, Guanajuato, Gto., México
| | - Alma R Corrales-Escobosa
- Universidad de Guanajuato, Departamento de Química, División de Ciencias Naturales y Exactas, Campus Guanajuato., Noria Alta S/N, 36050, Guanajuato, Gto., México
| | - Claudia de León-Solis
- Instituto de Investigaciones Químicas, Biológicas, Biomédicas y Biofísicas., Universidad Mariano Gálvez, Guatemala, Guatemala
| | - César R Solorio-Alvarado
- Universidad de Guanajuato, Departamento de Química, División de Ciencias Naturales y Exactas, Campus Guanajuato., Noria Alta S/N, 36050, Guanajuato, Gto., México
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7
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Sharp-Bucknall L, Tania, Sceney M, Barwise L, Dutton JL. Electrophilic activation of molecular bromine mediated by I(III). Dalton Trans 2023; 52:16472-16479. [PMID: 37873647 DOI: 10.1039/d3dt02999a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2023]
Abstract
In pursuit of a genuine bromo-λ3-iodane, it has been found that the combination of Br2 and electron deficient λ3-iodanes can result in the delivery of both bromine atoms from Br2 to a range of aryl substrates, some highly deactivated. These brominations occur rapidly in common chlorinated solvents at room temperature and can be achieved with the catalytic activation of commercially available PhI(OAc)2 and PhI(OTFA)2. para-NO2 substituted derivatives are employed to direct bromination towards more deactivated substrates. The mechanism of Br2 activation is discussed with insights being made, however it remains unclear.
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Affiliation(s)
- Lachlan Sharp-Bucknall
- Department of Biochemistry and Chemistry, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Victoria, Australia.
| | - Tania
- Department of Biochemistry and Chemistry, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Victoria, Australia.
| | - Marcus Sceney
- Department of Biochemistry and Chemistry, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Victoria, Australia.
| | - Lachlan Barwise
- Department of Biochemistry and Chemistry, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Victoria, Australia.
| | - Jason L Dutton
- Department of Biochemistry and Chemistry, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Victoria, Australia.
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8
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Zheng T, Xu J, Cheng S, Ye J, Ma S, Tong R. Green Halogenation of Indoles with Oxone-Halide. J Org Chem 2023; 88:11497-11503. [PMID: 37499121 DOI: 10.1021/acs.joc.3c00638] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/29/2023]
Abstract
Oxidative functionalization of indoles is one of the most widely used approaches to exploit the synthetic utility of indoles. In continuation of our research interest in the green oxidation of indoles, we further explore the oxidation of indoles with oxone-halide and discover that the protecting group on the nitrogen of indoles plays a decisive role in controlling the pathways of indole oxidation with oxone-halide. An electron-withdrawing group on the nitrogen of indoles (N-EWG) enables C2 halogenation with stoichiometric halide, while C3 halogenation could be selectively achieved by using stoichiometric halide without dependence on the electronic property of the protecting group on the indole nitrogen. Different from our previous results obtained by using catalytic halide, these findings lead to the development of an environmentally friendly, efficient, and mild protocol for access to 2- or 3-haloindoles (chloro and bromo). As compared to the previous synthetic methods for 2-/3-haloindoles, our method exploits the in situ-generated reactive halogenating species from oxone-halide for halogenation of indoles and thus eliminates the use of stoichiometric halogenating agents and the production of toxic and hazardous organic byproducts derived from oxidants.
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Affiliation(s)
- Tao Zheng
- School of Pharmacy, Guizhou University of Traditional Chinese Medicine, Guiyang 550025, China
| | - Jun Xu
- School of Pharmacy, Guizhou University of Traditional Chinese Medicine, Guiyang 550025, China
| | - Shaojun Cheng
- School of Pharmacy, Guizhou University of Traditional Chinese Medicine, Guiyang 550025, China
| | - Jianghai Ye
- School of Pharmacy, Guizhou University of Traditional Chinese Medicine, Guiyang 550025, China
| | - Shiqiang Ma
- Department of Chemistry, The Hong Kong University of Science and Technology, Clearwater Bay, Kowloon 999077, Hong Kong, China
| | - Rongbiao Tong
- Department of Chemistry, The Hong Kong University of Science and Technology, Clearwater Bay, Kowloon 999077, Hong Kong, China
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9
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Sikdar P, Choudhuri T, Paul S, Das S, Bagdi AK. K 2S 2O 8-Promoted Consecutive Tandem Cyclization/Oxidative Halogenation: Access to 3-Halo-Pyrazolo[1,5- a]pyrimidines. ACS OMEGA 2023; 8:23851-23859. [PMID: 37426282 PMCID: PMC10323951 DOI: 10.1021/acsomega.3c02270] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Accepted: 06/09/2023] [Indexed: 07/11/2023]
Abstract
A one-pot methodology has been developed to synthesize 3-halo-pyrazolo[1,5-a]pyrimidine derivatives through the three-component reaction of amino pyrazoles, enaminones (or chalcone), and sodium halides. The use of easily accessible 1,3-biselectrophilic reagents like enaminones and chalcone offers a straightforward approach for the synthesis of 3-halo-pyrazolo[1,5-a]pyrimidines. The reaction proceeded through a cyclocondensation reaction between amino pyrazoles with enaminones/chalcone in the presence of K2S2O8 followed by oxidative halogenations by NaX-K2S2O8. Mild and environmentally benign reaction conditions, wide functional group tolerance, and scalability of the reaction are the attractive facet of this protocol. The combination of NaX-K2S2O8 is also beneficial for the direct oxidative halogenations of pyrazolo[1,5-a]pyrimidines in water.
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10
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Metformin, a biological and synthetic overview. Bioorg Med Chem Lett 2023; 86:129241. [PMID: 36933671 DOI: 10.1016/j.bmcl.2023.129241] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2022] [Revised: 03/03/2023] [Accepted: 03/12/2023] [Indexed: 03/18/2023]
Abstract
Metformin is the most widely known anti-hyperglycemic, officially acquired by the USA government in 1995 and in 2001 it became the most prescribed treatment for type II diabetes. But how did it become the must-use drug for this disease in such a short period of time? it all started with traditional medicine, by using a plant known as "goat's rue" for the reduction of blood glucose levels. Its use arose in 1918 and evolved to the metformin synthesis in laboratories a couple of years later, using very rudimentary methods which involved melting and strong heating. Thus, a first synthetic route that allowed the preparation of the initial metformin derivates was established. Some of these resulted toxics, and others outperformed the metformin, reducing the blood glucose levels in such efficient way. Nevertheless, the risk and documented cases of lactic acidosis increased with metformin derivatives like buformin and phenformin. Recently, metformin has been widely studied, and it has been associated and tested in the treatment of type II diabetes, cancer, polycystic ovarian syndrome, cell differentiation to oligodendrocytes, reduction of oxidative stress in cells, weight reduction, as anti-inflammatory and even in the recent COVID-19 disease. Herein we briefly review and analyze the history, synthesis, and biological applications of metformin and its derivates.
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11
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Sharp-Bucknall L, Sceney M, White KF, Dutton JL. Synthesis, structural characterization, reactivity and catalytic activity of mixed halo/triflate ArI(OTf)(X) species. Dalton Trans 2023; 52:3358-3370. [PMID: 36809478 DOI: 10.1039/d3dt00275f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Both mixed λ3-iodoarenes and λ3-iodoarenes possessing -OTf ligands are coveted for their enhanced reactivities. Here we describe the synthesis, reactivity, and comprehensive characterisation of two new ArI(OTf)(X) species, a class of compound that were previously only invoked as reactive intermediates where X = Cl, F and their divergent reactivity with aryl substrates. A new catalytic system for electrophilic chlorination of deactivated arenes using Cl2 as the chlorine source and ArI/HOTf as the catalyst is also described.
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Affiliation(s)
| | - Marcus Sceney
- Department of Chemistry, La Trobe University, Melbourne, Victoria, Australia.
| | - Keith F White
- Department of Chemistry, La Trobe University, Melbourne, Victoria, Australia.
| | - Jason L Dutton
- Department of Chemistry, La Trobe University, Melbourne, Victoria, Australia.
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12
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Jian Y, Liang P, Li X, Shao H, Ma X. Controllable transformation of indoles using iodine(III) reagent. Org Biomol Chem 2022; 21:179-186. [PMID: 36472160 DOI: 10.1039/d2ob01951e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Herein, an efficient and highly functional group-compatible procedure for controllable transformation of indoles by the combination of phenyliodine bis(trifluoroacetate) (PIFA) with n-Bu4NCl·H2O (TBAC) was exploited. Through controlling the amount of PIFA and TBAC from one to three equivalents, 3-chloro-indoles, 3-chloro-2-oxindoles, and 3,3-dichloro-2-oxindoles were obtained, respectively, in satisfactory to excellent yields. The advantages of the protocol include mild conditions, facile process with short reaction time, high yields, satisfactory functional group tolerance, and the use of PIFA, which is an air- and moisture-stable promoter. The mechanism studies showed that the reaction may proceed through a halonium ion species-mediated halogenation-elimination-halogenation stepwise process.
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Affiliation(s)
- Yinxiang Jian
- Natural Products Research Centre, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, 610041, People's Republic of China. .,University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
| | - Peng Liang
- Natural Products Research Centre, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, 610041, People's Republic of China. .,School of Chemical Engineering, Institute of Pharmaceutical Engineering Technology and Application, Key Laboratory of Green Chemistry of Sichuan Institutes of Higher Education, Sichuan University of Science & Engineering, Xueyuan Street 180, Huixing Road, Zigong, Sichuan 643000, People's Republic of China
| | - Xiaoyan Li
- Natural Products Research Centre, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, 610041, People's Republic of China. .,University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
| | - Huawu Shao
- Natural Products Research Centre, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, 610041, People's Republic of China. .,University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
| | - Xiaofeng Ma
- Natural Products Research Centre, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, 610041, People's Republic of China. .,University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
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