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A simple and facile iodination method of didechlorotiacumicin B and aromatic compounds

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Science China Chemistry 2021年第10期64卷 1736-1742页

作者： Haibo Zhang Liping Zhang Imran Khan Guangtao Zhang Yiguang Zhu Changsheng Zhang Key Laboratory of Tropical Marine Bio-resources and Ecology Guangdong Key Laboratory of Marine Materia MedicaRNAM Center for Marine MicrobiologySouth China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China Sanya Institute of Oceanology SCSIOYazhou Scientific BaySanya 572000China Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou) Guangzhou 511458China University of Chinese Academy of Sciences Beijing 100049China

Tiacumicin B(also known as fidaxomicin or difimicin)is a marketed 18-membered macrolide antibiotic for the treatment of Clostridium difficile *** B is structurally characterized with two chlorine atoms substituted on the aromatic ring,which is installed by the halogenase Tia *** the study on halide compatibility of Tia M,a facile and nonenzymatic iodination method of didechlorotiacumicin B was discovered,requiring Na I,acid and air for iodination at room *** method was also amenable to other 9 aromatic substrates with electron-rich sites for iodination.

关键词： iodination tiacumicin metal-free facile chemistry

Freeze-induced acceleration of iodide oxidation and consequent iodination of dissolved organic matter to form organoiodine compounds

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Journal of Environmental Sciences 2024年第10期144卷 67-75页

作者： Xuexin Gong Mei He Zhineng Hao Rusong Zhao Jingfu Liu School of Resources and Environment Yangtze UniversityWuhan 430100China State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China Qilu University of Technology(Shandong Academy of Sciences) Shandong Analysis and Test CenterKey Laboratory for Applied Technology of Sophisticated Analytical Instruments of Shandong ProvinceJinan 250014China Institute of Environment and Health Jianghan UniversityWuhan 430056China

Freeze-induced acceleration of I–oxidation and the consequent iodination of dissolved organic matter(DOM)contribute to the formation of organoiodine compounds(OICs)in cold *** formed OICs may be a potentially important source of risk and are very closely with the environment and human ***,we investigated the acceleration effects of the freeze process on I–oxidation and the formation of *** comparison to reactive iodine species(RIS)formed in aqueous solutions,I–oxidation and RIS formation were greatly enhanced in frozen solution and were affected by pH,and the content of I–and O_(2).Freeze-thaw process further promoted I–oxidation and the concentration of RIS reached 45.7μmol/L after 6 freeze-thaw *** consequent products of DOM iodination were greatly promoted in terms of both concentration and *** total content of OICs ranged from 0.02 to 2.83μmol/L under various *** 183–1197 OICs were detected by Fourier transform ion cyclotron resonance mass spectrometry,and more than 96.2%contained one or two iodine *** OICs had aromatic structures and were formed via substitution and addition *** findings reveal an important formation pathway for OICs and shed light on the biogeochemical cycling of iodine in the natural aquatic environment.

关键词： Freeze process Dissolved organic matter(DOM) iodination Organoiodine compounds(OICs) Ultrahigh resolution mass spectrometry

Electrochemically Generated Iodine Cations from a Glassy Carbon Electrode for Highly Selective iodination of Anisole

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Transactions of Tianjin University 2022年第6期28卷 433-439页

作者： Liang Yan Haitao Lei Pengcheng Yang Wei Zhang Shaanxi Coal Chemical Technology Research Institute Co. LtdXi’an 710100China School of Chemistry and Chemical Engineering Shaanxi Normal UniversityXi’an 710119China

The synthesis of aryl iodides from commercially available raw chemicals by simple,cheap and green strategies is of fundamental signifi *** iodides can undergo a series of homo-/cross-coupling reactions for the synthesis of important industrial chemicals and *** methods require the electrophilic substitution on aromatic compounds by iodine or hypervalent iodine compounds,which suff ers from the use of erosive halogens or hazardous *** the development of green chemistry in the fi eld of electrochemical synthesis,anodic oxidation-derived I^(+)cations have been used for substitution ***,the selectivity of the iodination by these electrochemical methods remains *** believed that the anolyte is contaminated by trace platinum species from the working ***,we report the generation of active I^(+)species from the anodic oxidation of I_(2) in acetonitrile using a glassy carbon *** the presence of H^(+),electrolyte prepared with a glassy carbon anode can react with anisole to selectively form 4-iodoanisole with a yield as high as 97%.On contrast,the electrolytes prepared from Pt and graphite anodes fi nished the reaction with yields of 16%and 60%for 4-iodoanisole,*** electrochemical method also applies to the iodination of toluene,benzonitrile and bromobenzene,delivering the target para-iodination products with 92%,84%,and 73%yields,***,an atom-effi cient and highly selective aryl iodination method was developed without the use of excessive oxidants.

关键词： iodination Electrochemistry Anodic oxidation Aryl iodides Selectivity

A simple and efficient method for solvent-free iodination of hydroxylated aromatic aldehydes and ketones using iodine and iodic acid by grinding method

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Chinese Chemical Letters 2010年第8期21卷 914-918页

作者： Archana Vibhute Shyam Mokle Khushal Karamunge Vasant Gurav Yeshwant Vibhute Laboratory of Organic Synthesis P.G.Department of ChemistryYeshwant MahavidyalayaNanded 431602(M.S.)India

Green,mild and efficient iodination of hydroxylated aromatic aldehydes and ketones using iodine and iodic acid in the solidstate by grinding under solvent-free conditions at room *** method provides several advantages... 详细信息

关键词： iodination Aromatic aldehydes Aromatic ketones Grinding

Efficient iodination of aromatic compounds using potassium ferrate supported on montmorillonite

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Chinese Chemical Letters 2011年第12期22卷 1427-1430页

作者： Hoda Keipour Mohammad A.Khalilzadeh Bita Mohtat Abolfazl Hosseini Daryoush Zareyee a Department of Chemistry Islamic Azad UniversityKaraj BranchKarajIran b Department of Chemistry Qaemshahr BranchIslamic Azad UniversityQaemshahrIran b Department of Chemistry Qaernshahr BranchIslamic Azad UniversityQaemshahrIran

Potassium ferrate impregnated on montmorillonite is a mild,cheap,and non-toxic reagent for the iodination of phenols, including naphthol,aromatic amines,and heterocyclic substrates in fair to excellent yields by a sim... 详细信息

关键词： iodination Heterocyclic and aromatic compounds Potassium ferrate

Direct iodination of Aromatic Compounds with Polyvinylpyrrolidone Supported Hydrogen Peroxide （PVP-H2O2） and Potassium Iodide or Molecular Iodine

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Chinese Journal of Chemistry 2006年第8期24卷 1077-1079页

作者： POURALI, Ali Reza GHANEI, Mersieh Department of Chemistry Damghan University of Basic Sciences Damghan Iran

Hydrogen peroxide was supported on polyvinylpyrrolidone to afford a stable and mild oxidizing reagent. Activated aromatic compounds were reacted with PVP-H2O2 in the presence of KI or I2 and a catalytic amount of H3PW... 详细信息

关键词： iodinated aromatic compounds iodination hydrogen peroxide supported reagents

Aryl C–H iodination: are there actual flavin-dependent iodinases in nature?

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Science China Chemistry 2021年

作者： YuyangZhang LinChen HongpingChen TingtingHuang QingShi XiaozhengWang YanWang Man-ChengTang Ning-YiZhou ShuangjunLin SyntheticBiologyEngineeringLabofHenanProvince SchoolofLifeScienceandBiotechnologyXinxiangMedicalUniversity StateKeyLaboratoryofMicrobialMetabolism JointInternationalLaboratoryonMetabolic&DevelopmentalSciencesSchoolofLifeSciences&BiotechnologyShanghaiJiaoTongUniversity

Flavin-dependent halogenases（FDHs） are well known to introduce carbon halide bonds（mainly C–Cl and C–Br） into natural products with the assistance of a partner protein flavin reductase to generate reduced flavin（FADH2or FMNH2）. Compared with the common chloride-and bromide-containing natural products（approximately 5,000 compounds）, iodinated natural products（approximately 100 compounds） are very limited. Specific iodinases have also rarely been identified in nature to date. This study discovered a novel relationship between iodination and flavin reductases for the first time. Through mechanistic studies, it was identified that peroxide（H2O2） was released from the uncoupling reaction of flavin reductases and then reacted with iodide ions（I-） to produce hypoiodous acid（IOH） for the final iodination. Furthermore, this study also unintentionally verified that the recently reported flavin-dependent iodinase VirX1 from the marine virus and its two homologs（MBG and NCV） did not catalyze iodination in the in vitro biochemical system but likely belonged to a new phylogenetic clade in the tryptophan halogenase superfamily. As a consequence, actual flavin-dependent iodinases in nature remain to be discovered by the scientific community in the future.

关键词： flavin-dependent halogenase flavin reductase iodination H2O2 iodinase

Study on the iodination of uracil derivatives

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Journal of Chinese Pharmaceutical Sciences 2010年第2期19卷 146-150页

作者：李立覃华张亮王孝伟刘俊义北京大学医学部药学院化学生物学系北京100191 北京大学医学部天然药物及仿生药物国家重点实验室北京100191

5-Iodouracil derivatives have interesting biological activities and can serve as important substrates for the metal-catalyzed cross-coupling reactions to introduce alkyl, alkenyl, and alkynyl groups to the C-5 position of uracil derivatives. In order to find a good method to iodinate directly the C-5 of uracil derivatives, we investigated three methods, which included iodine/lead （IV） dioxide, iodine/ammonium hexanitratocerate （CAN） and iodine chloride, and examined their reactivity to different types of uracil and thiouracil derivatives.

关键词： iodination Lead (IV) dioxide Ammonium hexanitratocerate Iodine chloride Uracil 2-Thiouracil

Zirconium-mediated Selective Synthesis of 1,4-Dialkyl（aryl）-hexa-substituted Benzenes from Two Silyl-substituted Alkynes and One Internal Alkyne

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Chemical Research in Chinese Universities 2016年第3期32卷 366-372页

作者： LI Junqiu ZHANG Jiqian QU Hongmei LIU Jun LI Juan ZHOU Lishan Key Laboratory of Systems Bioengineering Ministry of Education Department of Pharmaceutical Engineering School of Chemical Engineering and Technology Tianjin University Tianjin 300072 P. R. China Nantong Dongchang Chemical Industrial Co. Ltd. Nantong 226407 P. R. China CNOOC Tianjin Chemical Research and Design Institute Tianjin 300131 P. R. China

Based on the formation of 2,5-bis（trimethylsilyl）-zirconacyclopentadienes from two silylalkynes with CpEZrBu2 and the Cu-mediated formation of 1,4-disilylbenzene via the cycloaddition of zirconacyclopentadienes to disubstituted alkynes, a selective synthesis of 1,4-dialkyl（aryl）-hexa-substituted benzenes was achieved followed by iodination and coupling reaction. The coupling reactions were carried out with either organolithium reagent or orga- nozinc reagent（Negishi coupling）, depending on the electrophilic species.

关键词： Zirconium Hexa-substituted benzene iodination Coupling reaction