We herein present an efficient denitrative iodination method of(hetero)nitroarenes mediated by commercially available and cost-effective hydroiodic acid(HI).During the reaction process,HI plays its dual roles as both ...We herein present an efficient denitrative iodination method of(hetero)nitroarenes mediated by commercially available and cost-effective hydroiodic acid(HI).During the reaction process,HI plays its dual roles as both the sustainable reductant of nitro group and iodine source in the iodination step,which successfully integrates three steps into a one-pot procedure and significantly simplifies the reaction system.This approach enables a smooth metal-free conversion of nitroarenes to corresponding aryl iodides via one-pot process,exhibits a broad substrate scope and good reaction efficiency,and was conveniently applied in the concise synthesis of pharmaceuticals.展开更多
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 regions.The formed OICs may be a potentially...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 regions.The formed OICs may be a potentially important source of risk and are very closely with the environment and human health.Herein,we investigated the acceleration effects of the freeze process on I–oxidation and the formation of OICs.In 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 cycles.The consequent products of DOM iodination were greatly promoted in terms of both concentration and number.The total content of OICs ranged from 0.02 to 2.83μmol/L under various conditions.About 183–1197 OICs were detected by Fourier transform ion cyclotron resonance mass spectrometry,and more than 96.2%contained one or two iodine atoms.Most OICs had aromatic structures and were formed via substitution and addition reactions.Our findings reveal an important formation pathway for OICs and shed light on the biogeochemical cycling of iodine in the natural aquatic environment.展开更多
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 positio...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.展开更多
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 temperature.This method provides sever...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 temperature.This method provides several advantages such as environmentally friendly,short reaction times,high yields,non-hazardous and simple work-up procedure.展开更多
Palladium-catalyzed highly meta-selective C—H iodination of phenylacetic acid,benzylphosphonate and benzylsulfonate scaffolds with molecular I2 is developed using a pyridine-type template.The practical ester linkages...Palladium-catalyzed highly meta-selective C—H iodination of phenylacetic acid,benzylphosphonate and benzylsulfonate scaffolds with molecular I2 is developed using a pyridine-type template.The practical ester linkages enable the directing template easily installed and readily removed.The substrate scope is broad,and alkyl,methoxyl,trifluomethyl,and halo substituents are compatible with this reaction.Further transformations of ibuprofen iodide intermediates by Pd-catalyzed C—C and C-heteroatom bond formation illustrate the broad utility of this method.展开更多
The synthesis of aryl iodides from commercially available raw chemicals by simple,cheap and green strategies is of fundamental signifi cance.Aryl iodides can undergo a series of homo-/cross-coupling reactions for the ...The synthesis of aryl iodides from commercially available raw chemicals by simple,cheap and green strategies is of fundamental signifi cance.Aryl iodides can undergo a series of homo-/cross-coupling reactions for the synthesis of important industrial chemicals and materials.Traditional 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 oxidants.With the development of green chemistry in the fi eld of electrochemical synthesis,anodic oxidation-derived I^(+)cations have been used for substitution reactions.However,the selectivity of the iodination by these electrochemical methods remains unsatisfactory.We believed that the anolyte is contaminated by trace platinum species from the working electrode.Herein,we report the generation of active I^(+)species from the anodic oxidation of I_(2) in acetonitrile using a glassy carbon electrode.With 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,respectively.This electrochemical method also applies to the iodination of toluene,benzonitrile and bromobenzene,delivering the target para-iodination products with 92%,84%,and 73%yields,respectively.Thus,an atom-effi cient and highly selective aryl iodination method was developed without the use of excessive oxidants.展开更多
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...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 simple isolation procedure.展开更多
A simple and efficient method for the iodination of aromatic compounds has been achieved in the presence of iodine and 1,4- bis（triphenylphosphonium）-2-butene peroxodisulfate.
Arsenic(As)contamination in vegetables poses significant ecological and health risks,raising substantial public concern.While arsenic accumulation and transformation have been studied,the in-situ iodination effects an...Arsenic(As)contamination in vegetables poses significant ecological and health risks,raising substantial public concern.While arsenic accumulation and transformation have been studied,the in-situ iodination effects and mechanisms under co-contamination with arsenic and phenolic pollutants(e.g.,bisphenol F)remain unclear.This study addresses this gap by exposing Brassica chinensis L.to hydroponic solutions containing sodium hydrogen arsenate heptahydrate(As(V))at concentrations of 0-100μmol/L,BPF at 3 mg/L,and iodide ions at 40μmol/L under environmentally relevant conditions.Results demonstrate that As(V)enhances the iodination of BPF by increasing levels of reactive oxygen species(H_(2)O_(2)and•OH)and elevating peroxidase(POD)activity,as confirmed by transcriptomic analysis.As the concentration of As(V)increased from 0 to 100μmol/L,the diversity and concentration of iodinated BPF products in the roots exhibited a dose-dependent increase,while the variety of iodinated products in the leaves also showed a corresponding rise.Gaussian calculations and mass spectrometry identified the specific substitution sites and the number of iodide atoms incorporated into BPF molecules.By combining toxicity predictions of iodinated BPF using the Toxicity Estimation Software Tool(T·E·S·T)and the Ecological Structure-Activity Relationships(ECOSAR)model with measurements of HepG2 cell viability and lactate dehydrogenase(LDH)activity in the cell culture medium,it was found that the toxicity of iodinated BPF products in plants increased following the addition of As(V).This study highlights the combined risks of arsenic and bisphenol contamination,revealing arsenic’s role in enhancing bisphenol iodination and toxicity in plants.展开更多
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...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 H3PW12O40 in refluxing CH2Cl2 to afford the corresponding iodinated arenes.展开更多
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 (...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 (FADH_(2)or FMNH_(2)).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 (H_(2)O_(2)) 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 Vir X1 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.展开更多
A facile method for decarboxylative amination driven by the photoactivity of electron donor-acceptor(EDA)com-plexes assembled from iodide salts and redox-active esters has been proposed.A broad array of acyclic and cy...A facile method for decarboxylative amination driven by the photoactivity of electron donor-acceptor(EDA)com-plexes assembled from iodide salts and redox-active esters has been proposed.A broad array of acyclic and cyclic protected amines were readily synthesized without requiring exogenous transition-metal or photoredox catalysts.Moreover,this ap-proach facilitates late-stage functionalization of complex molecules and is amenable to continuous-flow process on gram scale.展开更多
Tiacumicin B(also known as fidaxomicin or difimicin)is a marketed 18-membered macrolide antibiotic for the treatment of Clostridium difficile infections.Tiacumicin B is structurally characterized with two chlorine ato...Tiacumicin B(also known as fidaxomicin or difimicin)is a marketed 18-membered macrolide antibiotic for the treatment of Clostridium difficile infections.Tiacumicin B is structurally characterized with two chlorine atoms substituted on the aromatic ring,which is installed by the halogenase Tia M.During 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 temperature.This method was also amenable to other 9 aromatic substrates with electron-rich sites for iodination.展开更多
Iodine is an essential element for the synthesis of thyroid hormones.Iodine deficiency increases the burden on thyroid function and causes harm to health.The identification of convenient and reliable biomarkers for as...Iodine is an essential element for the synthesis of thyroid hormones.Iodine deficiency increases the burden on thyroid function and causes harm to health.The identification of convenient and reliable biomarkers for assessing iodine nutritional status is essential for evaluating iodine intake.Urinary iodine concentration(UIC)is commonly used for population level iodine status assessment but is less reliable for individuals.A 24-h urine sample is more accurate but difficult to collect[1].Thyroid volume(Tvol)and goiter rate are suitable for evaluating the long-term iodine nutritional status in populations[2].Blood indicator collection is an invasive procedure.展开更多
A recent paper published in Journal of the American Chemical Society by W.Zhang and co-workers reported a ground-breaking advance by establishing 209 Bi and 127 I ultra-wideline solid-state NMR(UW SSNMR)as powerful to...A recent paper published in Journal of the American Chemical Society by W.Zhang and co-workers reported a ground-breaking advance by establishing 209 Bi and 127 I ultra-wideline solid-state NMR(UW SSNMR)as powerful tools for probing bismuth and iodine ions in metal-organic frameworks(MOFs),despite the severe challenges associated with their exceptionally large quadrupolar interactions,and enabled the elucidation of key structural features that are otherwise difficult to access[1].展开更多
Objective This study aimed to reexplore minimum iodine excretion and to build a dietary iodine recommendation for Chinese adults using the obligatory iodine loss hypothesis.Methods Data from 171 Chinese adults(19–21 ...Objective This study aimed to reexplore minimum iodine excretion and to build a dietary iodine recommendation for Chinese adults using the obligatory iodine loss hypothesis.Methods Data from 171 Chinese adults(19–21 years old)were collected and analyzed based on three balance studies in Shenzhen,Yinchuan,and Changzhi.The single exponential equation was accordingly used to simulate the trajectory of 24 h urinary iodine excretion as the low iodine experimental diets offered(iodine intake:11-26μg/day)and to further deduce the dietary reference intakes(DRIs)for iodine,including estimated average requirement(EAR)and recommended nutrient intake(RNI).Results The minimum iodine excretion was estimated as 57,58,and 51μg/day in three balance studies,respectively.Moreover,it was further suggested as 57,58,and 51μg/day for iodine EAR,and 80,81,and 71μg/day for iodine RNI or expressed as 1.42,1.41,and 1.20μg/(day·kg)of body weight.Conclusion The iodine DRIs for Chinese adults were established based on the obligatory iodine loss hypothesis,which provides scientific support for the amendment of nutrient requirements.展开更多
Groundwater is the main water supply source in the Tarim Basin in China.Endemic disease caused by high iodine(I)groundwater in the Tarim Basin was reported previously.Therefore,it is crucial to systematically identify...Groundwater is the main water supply source in the Tarim Basin in China.Endemic disease caused by high iodine(I)groundwater in the Tarim Basin was reported previously.Therefore,it is crucial to systematically identify the distribution and genesis of groundwater I.Based on hydrochemical analysis of 717 groundwater samples collected in 2015–2018,spatial distribution and hydrogeochemistry characteristic of high I groundwater in different aquifers were analyzed.Results showed that groundwater I ranged between<10.00 and 4000.00μg/L(mean of 53.71μg/L).High I groundwater(I>100.00μg/L)accounted for 7.25%of the total samples.Horizontally,groundwater I significantly increased from recharge zone(RZ)to transition zone(TZ)and to evaporation zone(EZ).Vertically,groundwater in shallow confined aquifer(SCA)had the greatest I concentration,followed by single-structure phreatic aquifer(SSPA),phreatic aquifer in confined groundwater area(PACGA),while groundwater in deep confined aquifer(DCA)generally had low I concentration.Groundwater I enrichment in SSPA was mainly affected by organic matter(OM)decomposition and that in SCA was mainly affected by evaporite mineral dissolution,OM decomposition under alkaline environment.While I enrichment in groundwater of PACGA was restrained under neutral environment.Lacustrine sedimentary environment was crucial for I enrichment in groundwater.Besides,fine-grained lithology of aquifer,smooth topographic slope,shallow buried depth of groundwater,weak alkaline and reducing environment,reductive dissolution of iron oxide/hydroxide minerals and OM decomposition were advantageous to I enrichment in groundwater.展开更多
Currently,iodine-compatible cathodes for iodine propulsion systems that can provide ampere-level electron currents with a reasonable power consumption are lacking.In this study,a conventional LaB_(6)hollow cathode mad...Currently,iodine-compatible cathodes for iodine propulsion systems that can provide ampere-level electron currents with a reasonable power consumption are lacking.In this study,a conventional LaB_(6)hollow cathode made with iodine-resistant materials was designed and tested in an iodine-compatible vacuum facility.The ignition characteristics,the V-I(Volt-Ampere characteristic)curve,and long steady-state discharge sequence of the iodine hollow cathode were analyzed and compared with those using a krypton propellant.After the experiment,the composition of the cathode emitter was studied by scanning electron microscope and energy-dispersive X-ray spectroscopy(EDS).The results show that ignition takes>10 s to reach a steady state,and the discharge voltage of the iodine was 25-95 V higher than that of krypton.According to the EDS results,this was mainly caused by emitter contamination with iron from the stainless-steel components of the cathode and oxygen from the iodine feed system.The iodine hollow cathode achieved a cumulative 12.5 h stable discharge,with the longest single discharge of 5 h and a 3%change in the inner diameter of the emitter.展开更多
Dear Editor,In recent years,there has been a significant upward trend in the detection rate of thyroid diseases among military flight personnel[1].Thyroid diseases not only pose a serious threat to the health of fligh...Dear Editor,In recent years,there has been a significant upward trend in the detection rate of thyroid diseases among military flight personnel[1].Thyroid diseases not only pose a serious threat to the health of flight personnel but also have negative impacts on the aviation safety and combat effectiveness of troops.It has been confirmed that the occurrence and progression of thyroid diseases are closely linked to dietary iodine intake.Studies have manifested that long-term excessive or insufficient iodine intake can lead to thyroid diseases[2,3].展开更多
Background:To evaluate sex‐related differences in the risk factors associated with nonhealing or recurrence of hyper-thyroidism(NHRH)in patients with Graves'disease(GD)treated with radioactive iodine.Methods:In t...Background:To evaluate sex‐related differences in the risk factors associated with nonhealing or recurrence of hyper-thyroidism(NHRH)in patients with Graves'disease(GD)treated with radioactive iodine.Methods:In total,285 patients were enrolled.Data on radioactive iodine(RAI)dosage,ultrasound indexes of the thyroid,and other clinical factors were collected.Patients were divided into NHRH and non‐NHRH(hypothyroidism or euthyroidism)groups based on treatment outcomes.Univariate and multivariate weighted logistic regression analyses were used to identify factors associated with NHRH.Sex‐specific analyses of these risk factors were also conducted.Results:There were no significant differences between the two groups in terms of sex,thyroid shear wave elastography velocity values,or pretreatment serum free thyroxine(FT4)levels.Thyroid volume and age were independently associated with NHRH,with the odds of NHRH gradually decreasing as age increased.In subgroup analyses,both age and thyroid volume were independent risk factors for NHRH in female patients(p<0.05),while in male patients,only FT4 was independently associated with NHRH(p<0.05).Conclusions:In patients of different sexes,the influence of thyroid volume,age,and FT4 on treatment outcomes exhibits distinct patterns.展开更多
基金the National Key Research and Development Project(No.2023YFF1205103)the National Natural Science Foundation of China(No.22371007)the Peking University Medicine plus X Pilot Program-Key Technologies R&D Project(No.2024YXXLHGG001)for financial support。
文摘We herein present an efficient denitrative iodination method of(hetero)nitroarenes mediated by commercially available and cost-effective hydroiodic acid(HI).During the reaction process,HI plays its dual roles as both the sustainable reductant of nitro group and iodine source in the iodination step,which successfully integrates three steps into a one-pot procedure and significantly simplifies the reaction system.This approach enables a smooth metal-free conversion of nitroarenes to corresponding aryl iodides via one-pot process,exhibits a broad substrate scope and good reaction efficiency,and was conveniently applied in the concise synthesis of pharmaceuticals.
基金This work was supported by the National Natural Science Foundation of China(Nos.22176199,21806173,and 42192571)the Jinan University and Institute Innovation Team Project(No.2021GXRC061).
文摘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 regions.The formed OICs may be a potentially important source of risk and are very closely with the environment and human health.Herein,we investigated the acceleration effects of the freeze process on I–oxidation and the formation of OICs.In 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 cycles.The consequent products of DOM iodination were greatly promoted in terms of both concentration and number.The total content of OICs ranged from 0.02 to 2.83μmol/L under various conditions.About 183–1197 OICs were detected by Fourier transform ion cyclotron resonance mass spectrometry,and more than 96.2%contained one or two iodine atoms.Most OICs had aromatic structures and were formed via substitution and addition reactions.Our findings reveal an important formation pathway for OICs and shed light on the biogeochemical cycling of iodine in the natural aquatic environment.
基金National Natural Science Foundation of China (Grant No.2017200720672008).
文摘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.
文摘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 temperature.This method provides several advantages such as environmentally friendly,short reaction times,high yields,non-hazardous and simple work-up procedure.
基金Shanghai Institute of Materia Medica,Chinese Academy of Sciences,National Natural Science Foundation of China(No.21772211)Youth Innovation Promotion Association CAS(Nos.2014229 and 2018293)+4 种基金Institutes for Drug Discovery and Development,Chinese Academy of Sciences(No.CASIMM0120163006)Science and Technology Commission of Shanghai Municipality(No.17JC1405000)Program of Shanghai Academic Research Leader(No.19XD1424600)National Science&Technology Major Project“Key New Drug Creation and Manufacturing Program”,China(No.2018ZX09711002-006)the State Key Laboratory of Natural and Biomimetic Drugs for financial support。
文摘Palladium-catalyzed highly meta-selective C—H iodination of phenylacetic acid,benzylphosphonate and benzylsulfonate scaffolds with molecular I2 is developed using a pyridine-type template.The practical ester linkages enable the directing template easily installed and readily removed.The substrate scope is broad,and alkyl,methoxyl,trifluomethyl,and halo substituents are compatible with this reaction.Further transformations of ibuprofen iodide intermediates by Pd-catalyzed C—C and C-heteroatom bond formation illustrate the broad utility of this method.
文摘The synthesis of aryl iodides from commercially available raw chemicals by simple,cheap and green strategies is of fundamental signifi cance.Aryl iodides can undergo a series of homo-/cross-coupling reactions for the synthesis of important industrial chemicals and materials.Traditional 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 oxidants.With the development of green chemistry in the fi eld of electrochemical synthesis,anodic oxidation-derived I^(+)cations have been used for substitution reactions.However,the selectivity of the iodination by these electrochemical methods remains unsatisfactory.We believed that the anolyte is contaminated by trace platinum species from the working electrode.Herein,we report the generation of active I^(+)species from the anodic oxidation of I_(2) in acetonitrile using a glassy carbon electrode.With 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,respectively.This electrochemical method also applies to the iodination of toluene,benzonitrile and bromobenzene,delivering the target para-iodination products with 92%,84%,and 73%yields,respectively.Thus,an atom-effi cient and highly selective aryl iodination method was developed without the use of excessive oxidants.
基金the Islamic Azad University of Qaemshahr for financial support
文摘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 simple isolation procedure.
文摘A simple and efficient method for the iodination of aromatic compounds has been achieved in the presence of iodine and 1,4- bis（triphenylphosphonium）-2-butene peroxodisulfate.
基金supported by the National Key Research and Developmental Program of China(No.2022YFC3701301)the National Natural Science Foundation of China(Nos.42230706 and 42377428)+1 种基金the Shandong Provincial Natural Science Foundation,China(Nos.ZR2020ZD34 and ZR2023YQ031)the Instrument Improvement Funds of Shandong University Public Technology Platform(China)(No.ts20230108).
文摘Arsenic(As)contamination in vegetables poses significant ecological and health risks,raising substantial public concern.While arsenic accumulation and transformation have been studied,the in-situ iodination effects and mechanisms under co-contamination with arsenic and phenolic pollutants(e.g.,bisphenol F)remain unclear.This study addresses this gap by exposing Brassica chinensis L.to hydroponic solutions containing sodium hydrogen arsenate heptahydrate(As(V))at concentrations of 0-100μmol/L,BPF at 3 mg/L,and iodide ions at 40μmol/L under environmentally relevant conditions.Results demonstrate that As(V)enhances the iodination of BPF by increasing levels of reactive oxygen species(H_(2)O_(2)and•OH)and elevating peroxidase(POD)activity,as confirmed by transcriptomic analysis.As the concentration of As(V)increased from 0 to 100μmol/L,the diversity and concentration of iodinated BPF products in the roots exhibited a dose-dependent increase,while the variety of iodinated products in the leaves also showed a corresponding rise.Gaussian calculations and mass spectrometry identified the specific substitution sites and the number of iodide atoms incorporated into BPF molecules.By combining toxicity predictions of iodinated BPF using the Toxicity Estimation Software Tool(T·E·S·T)and the Ecological Structure-Activity Relationships(ECOSAR)model with measurements of HepG2 cell viability and lactate dehydrogenase(LDH)activity in the cell culture medium,it was found that the toxicity of iodinated BPF products in plants increased following the addition of As(V).This study highlights the combined risks of arsenic and bisphenol contamination,revealing arsenic’s role in enhancing bisphenol iodination and toxicity in plants.
文摘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 H3PW12O40 in refluxing CH2Cl2 to afford the corresponding iodinated arenes.
基金the National Natural Science Foundation of China(21632007,21661140002 for S.Lin81903525 for Y.Zhang)+1 种基金Research Fund for High-level Talents of Xinxiang Medical University(300-505272)Open Funding Project of State Key Laboratory of Microbial Metabolism,Shanghai Jiao Tong University(MMLKF2011)。
文摘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 (FADH_(2)or FMNH_(2)).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 (H_(2)O_(2)) 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 Vir X1 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.
文摘A facile method for decarboxylative amination driven by the photoactivity of electron donor-acceptor(EDA)com-plexes assembled from iodide salts and redox-active esters has been proposed.A broad array of acyclic and cyclic protected amines were readily synthesized without requiring exogenous transition-metal or photoredox catalysts.Moreover,this ap-proach facilitates late-stage functionalization of complex molecules and is amenable to continuous-flow process on gram scale.
基金the Key Science and Technology Project of Hainan Province(Key Science and Technology Project ZDKJ202018)the Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou,2019ZD0406)+2 种基金the Chinese Academy of Sciences(QYZDJ-SSW-DQC004)the National Natural Science Foundation of China(81872778,31630004,41911530078)the Ministry of Science and Technology of China(2018YFC1406705)。
文摘Tiacumicin B(also known as fidaxomicin or difimicin)is a marketed 18-membered macrolide antibiotic for the treatment of Clostridium difficile infections.Tiacumicin B is structurally characterized with two chlorine atoms substituted on the aromatic ring,which is installed by the halogenase Tia M.During 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 temperature.This method was also amenable to other 9 aromatic substrates with electron-rich sites for iodination.
基金supported by the National Natural Science Foundation of China(Grant numbers 82204041)Gansu Provincial Science and Technology Program Funded Projects(Grant numbers 22JR11RA184).
文摘Iodine is an essential element for the synthesis of thyroid hormones.Iodine deficiency increases the burden on thyroid function and causes harm to health.The identification of convenient and reliable biomarkers for assessing iodine nutritional status is essential for evaluating iodine intake.Urinary iodine concentration(UIC)is commonly used for population level iodine status assessment but is less reliable for individuals.A 24-h urine sample is more accurate but difficult to collect[1].Thyroid volume(Tvol)and goiter rate are suitable for evaluating the long-term iodine nutritional status in populations[2].Blood indicator collection is an invasive procedure.
基金supported by the National Natural Science Foundation of China(Grants 22472075 and 22272075).
文摘A recent paper published in Journal of the American Chemical Society by W.Zhang and co-workers reported a ground-breaking advance by establishing 209 Bi and 127 I ultra-wideline solid-state NMR(UW SSNMR)as powerful tools for probing bismuth and iodine ions in metal-organic frameworks(MOFs),despite the severe challenges associated with their exceptionally large quadrupolar interactions,and enabled the elucidation of key structural features that are otherwise difficult to access[1].
基金supported by the National Natural Science Foundation of China(Grant No.81872624)Fundamental Research Program of Shanxi Province(Grant No.202403021211139).
文摘Objective This study aimed to reexplore minimum iodine excretion and to build a dietary iodine recommendation for Chinese adults using the obligatory iodine loss hypothesis.Methods Data from 171 Chinese adults(19–21 years old)were collected and analyzed based on three balance studies in Shenzhen,Yinchuan,and Changzhi.The single exponential equation was accordingly used to simulate the trajectory of 24 h urinary iodine excretion as the low iodine experimental diets offered(iodine intake:11-26μg/day)and to further deduce the dietary reference intakes(DRIs)for iodine,including estimated average requirement(EAR)and recommended nutrient intake(RNI).Results The minimum iodine excretion was estimated as 57,58,and 51μg/day in three balance studies,respectively.Moreover,it was further suggested as 57,58,and 51μg/day for iodine EAR,and 80,81,and 71μg/day for iodine RNI or expressed as 1.42,1.41,and 1.20μg/(day·kg)of body weight.Conclusion The iodine DRIs for Chinese adults were established based on the obligatory iodine loss hypothesis,which provides scientific support for the amendment of nutrient requirements.
基金financially supported by the National Natural Science Foundation of China(Nos.42067035 and 42007161)Water Conservancy Engineering Key Discipline Project of Xinjiang Agricultural University(No.SLXK2019-10)the Opening Project of Xinjiang Key Laboratory of Hydraulic Engineering Security and Water Disasters Prevention in 2021(No.ZDSYS-JS-2021-10)。
文摘Groundwater is the main water supply source in the Tarim Basin in China.Endemic disease caused by high iodine(I)groundwater in the Tarim Basin was reported previously.Therefore,it is crucial to systematically identify the distribution and genesis of groundwater I.Based on hydrochemical analysis of 717 groundwater samples collected in 2015–2018,spatial distribution and hydrogeochemistry characteristic of high I groundwater in different aquifers were analyzed.Results showed that groundwater I ranged between<10.00 and 4000.00μg/L(mean of 53.71μg/L).High I groundwater(I>100.00μg/L)accounted for 7.25%of the total samples.Horizontally,groundwater I significantly increased from recharge zone(RZ)to transition zone(TZ)and to evaporation zone(EZ).Vertically,groundwater in shallow confined aquifer(SCA)had the greatest I concentration,followed by single-structure phreatic aquifer(SSPA),phreatic aquifer in confined groundwater area(PACGA),while groundwater in deep confined aquifer(DCA)generally had low I concentration.Groundwater I enrichment in SSPA was mainly affected by organic matter(OM)decomposition and that in SCA was mainly affected by evaporite mineral dissolution,OM decomposition under alkaline environment.While I enrichment in groundwater of PACGA was restrained under neutral environment.Lacustrine sedimentary environment was crucial for I enrichment in groundwater.Besides,fine-grained lithology of aquifer,smooth topographic slope,shallow buried depth of groundwater,weak alkaline and reducing environment,reductive dissolution of iron oxide/hydroxide minerals and OM decomposition were advantageous to I enrichment in groundwater.
基金supported by the National Key R&D Program of China(No.2022YFE0204100)the Key Program of University-Enterprise Joint Project of National Natural Science Foundation of China(No.U22B20120).
文摘Currently,iodine-compatible cathodes for iodine propulsion systems that can provide ampere-level electron currents with a reasonable power consumption are lacking.In this study,a conventional LaB_(6)hollow cathode made with iodine-resistant materials was designed and tested in an iodine-compatible vacuum facility.The ignition characteristics,the V-I(Volt-Ampere characteristic)curve,and long steady-state discharge sequence of the iodine hollow cathode were analyzed and compared with those using a krypton propellant.After the experiment,the composition of the cathode emitter was studied by scanning electron microscope and energy-dispersive X-ray spectroscopy(EDS).The results show that ignition takes>10 s to reach a steady state,and the discharge voltage of the iodine was 25-95 V higher than that of krypton.According to the EDS results,this was mainly caused by emitter contamination with iron from the stainless-steel components of the cathode and oxygen from the iodine feed system.The iodine hollow cathode achieved a cumulative 12.5 h stable discharge,with the longest single discharge of 5 h and a 3%change in the inner diameter of the emitter.
基金supported by the Military Medical Science and Technology Youth Cultivation Program of the Chinese PLA(17QNP023)the Key Projects of Medical Service Scientific Research of the Navy Medical Center(20M2302)the Military Logistics National Military Standard General Project of Chinese PLA(BHJ22B002).
文摘Dear Editor,In recent years,there has been a significant upward trend in the detection rate of thyroid diseases among military flight personnel[1].Thyroid diseases not only pose a serious threat to the health of flight personnel but also have negative impacts on the aviation safety and combat effectiveness of troops.It has been confirmed that the occurrence and progression of thyroid diseases are closely linked to dietary iodine intake.Studies have manifested that long-term excessive or insufficient iodine intake can lead to thyroid diseases[2,3].
基金suported by the National High Level Hospital Clinical Research Funding(2022-NHLHCRF-LX-02-03,2023-NHLHCRF-YXHZ-ZRZD-06)Ministry ofScience and Technology of the People's Republic ofChina,and National Natural Science Foundation ofChina(82071943,82273523).
文摘Background:To evaluate sex‐related differences in the risk factors associated with nonhealing or recurrence of hyper-thyroidism(NHRH)in patients with Graves'disease(GD)treated with radioactive iodine.Methods:In total,285 patients were enrolled.Data on radioactive iodine(RAI)dosage,ultrasound indexes of the thyroid,and other clinical factors were collected.Patients were divided into NHRH and non‐NHRH(hypothyroidism or euthyroidism)groups based on treatment outcomes.Univariate and multivariate weighted logistic regression analyses were used to identify factors associated with NHRH.Sex‐specific analyses of these risk factors were also conducted.Results:There were no significant differences between the two groups in terms of sex,thyroid shear wave elastography velocity values,or pretreatment serum free thyroxine(FT4)levels.Thyroid volume and age were independently associated with NHRH,with the odds of NHRH gradually decreasing as age increased.In subgroup analyses,both age and thyroid volume were independent risk factors for NHRH in female patients(p<0.05),while in male patients,only FT4 was independently associated with NHRH(p<0.05).Conclusions:In patients of different sexes,the influence of thyroid volume,age,and FT4 on treatment outcomes exhibits distinct patterns.
