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Divided or undivided? Electrolytic cells regulate site selectivity in C–H carboxylation of N-heteroarenes

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Chinese Chemical Letters 2023年第7期34卷 6-7页

作者： Chuang-Xin wang congyang wang Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Molecular Recognition and FunctionCAS Research/Education Center for Excellence in Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

The precise synthesis of molecules is of great significance to the fields of life science, material science, pharmaceutical chemistry and so on. The development of chemo-, regio-and stereo-selective reactions is therefore highly demanding in synthetic chemistry.Pyridines and related N-heteroarenes are core structures in various medicines, agricultural chemicals and bioactive molecules.

关键词： chemistry. selectivity precise

Wide hybridizations reveal the robustness of functional centromeres in Triticum-Aegilops species complex lines

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Journal of Genetics and Genomics 2024年第5期51卷 570-573页

作者： Yuhong Huang Qinghua Shi Chen Zhou Chunhui wang Yang Liu congyang Yi Handong Su Fangpu Han State Key Laboratory of Plant Cell and Chromosome Engineering Institute of Genetics and Developmental BiologyInnovation Academy for Seed DesignChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Bejing 100049China National Key Laboratory of Crop Genetic Improvement Hubei Hongshan LaboratoryHuazhong Agricultural UniversityWuhanHubei430070China

The Triticum-Aegilops complex groups demonstrated high cross-affinity with each other to overcome the barriers of distant hybridization(Loureiro et al.,2023).Distant hybridization involves two distinct yet closely related events:hybridization and genome doubling.Previous studies have indicated that bursts of transposable elements(TEs)can occur as a consequence or concomitant to hybridization or genome duplication(Parisod et al.,2010).This raises an important scientific question regarding how the TEs-rich centromere region copes with genomic shock(McClintock,1984).The Triticum-Aegilops species complexes,particularly in the F1,So,and subsequent early generations resulting from successive selfcrossing,offer an opportunity to investigate whether the centromere environment undergoes reconstruction and the associated mechanisms that maintain genomic stability.

关键词： centromere Triticum complex

Non-B-form DNA is associated with centromere stability in newly-formed polyploid wheat

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Science China(Life Sciences) 2024年第7期67卷 1479-1488页

作者： congyang Yi Qian Liu Yuhong Huang Chang Liu Xianrui Guo Chaolan Fan Kaibiao Zhang Yang Liu Fangpu Han Institute of Genetics and Developmental Biology Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

Non-B-form DNA differs from the classic B-DNA double helix structure and plays a crucial regulatory role in replication and transcription.However,the role of non-B-form DNA in centromeres,especially in polyploid wheat,remains elusive.Here,we systematically analyzed seven non-B-form DNA motif profiles(A-phased DNA repeat,direct repeat,G-quadruplex,inverted repeat,mirror repeat,short tandem repeat,and Z-DNA)in hexaploid wheat.We found that three of these non-B-form DNA motifs were enriched at centromeric regions,especially at the CENH3-binding sites,suggesting that non-B-form DNA may create a favorable loading environment for the CENH3 nucleosome.To investigate the dynamics of centromeric non-B form DNA during the alloploidization process,we analyzed DNA secondary structure using CENH3 ChIP-seq data from newly formed allotetraploid wheat and its two diploid ancestors.We found that newly formed allotetraploid wheat formed more non-B-form DNA in centromeric regions compared with their parents,suggesting that non-B-form DNA is related to the localization of the centromeric regions in newly formed wheat.Furthermore,non-B-form DNA enriched in the centromeric regions was found to preferentially form on young LTR retrotransposons,explaining CENH3's tendency to bind to younger LTR.Collectively,our study describes the landscape of non-B-form DNA in the wheat genome,and sheds light on its potential role in the evolution of polyploid centromeres.

关键词： non-B-form DNA polyploid wheat centromere retrotransposon

现代佛教文学的契理契机——以佛教小说真实观的建构为例

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宗教学研究 2024年第2期 113-119页

作者：王丛阳河南大学文学院

现代佛教小说是佛教文学中最为特殊的一部分,它是僧尼、信众的作家意识与信徒意识相博弈的结果。20世纪初,作为宣传工具的现代小说进入僧尼、信众视野,成为宣扬佛法、革新佛教的全新手段。然而小说尚虚构、佛教戒妄语,创作小说有悖于戒... 详细信息

现代佛教小说是佛教文学中最为特殊的一部分,它是僧尼、信众的作家意识与信徒意识相博弈的结果。20世纪初,作为宣传工具的现代小说进入僧尼、信众视野,成为宣扬佛法、革新佛教的全新手段。然而小说尚虚构、佛教戒妄语,创作小说有悖于戒律。于是僧尼、信众在教义范畴内进行主动调适,建构起独特的小说真实观,以此来消除破戒所招致的指责及内心的惶恐。佛教小说在20世纪初的发展很好地体现了中国佛教“契理契机”的原则。

关键词：佛教小说真实观契理契机

Diverse Fates of β-Silyl Radical under Manganese Catalysis： Hydrosilyla-tion and Dehydrogenative Silylation of Alkenes

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Chinese Journal of Chemistry 2018年第11期36卷 1047-1051页

作者： Xiaoxu Yang congyang wang Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Molecular Recognition and Function CAS Research/Education Center for Excellence in Molecular Sciences Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China University of Chinese Academy of Sciences Beijing 200049 China

Manganese‐catalyzed hydrosilylation of alkenes has been underdeveloped for a long time. Herein, we describe a general, chemo‐ and regio‐ selective hydrosilylation of alkenes by using the Mn(CO) 5 Br catalyst with ample substrate scopes. Meanwhile, dehydrogenative silylation of aryl olefins can be selectively achieved upon the catalysis of dinuclear Mn 2 (CO) 10 . Mechanistic experiments revealed diverse fates of the common intermediate β‐silyl radical, namely, hydrogen atom transfer (HAT) for the hydrosilylation and organometallic β‐H elimination for the dehydrogenative silylation of olefins.

关键词： manganese hydrosilylation dehydrogenative silylation alkene homogenous catalysis

Rhenium-Catalyzed Decarboxylative Tri-/Difluoromethylation of Styrenes with Fluorinated Carboxylic Acid-Derived Hypervalent Iodine Reagents

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Chinese Journal of Chemistry 2019年第12期37卷 1229-1233页

作者： Yin wang Yunhui Yang congyang wang Radiochemistry Laboratory School of Nuclear Science and TechnologyLanzhou UniversityLanzhouGansu 730000China Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Molecular Recognition and FunctionCAS Research/Education Center for Excellence in Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Physical Science Laboratory Huairou National Comprehensive Science CenterBeijing 101400China

Summary of main observation and conclusion Herein,unprecedented rhenium-catalyzed decarboxylative oxytri-/difluoromethylation and Heck-type trifluoromethylation of styrenes have been developed by using hypervalent iodine(Ⅲ)reagents derived from cheap,stable,and easy-handling fluorinated carboxylic acids.Mechanistic studies revealed a radical decarboxylative trifluoromethylation pathway occurring in these reactions.

关键词： valent iodine styrene

Manganese-catalyzed bicyclic annulations of imines and α,β-unsaturated esters via C-H activation

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Science China Chemistry 2016年第10期59卷 1301-1305页

作者： Yuanyuan Hu congyang wang Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Molecular Recognition and Function Institute of ChemistryChinese Academy of Sciences University of Chinese Academy of Sciences

A manganese-catalyzed bicyclic annulation of imines with α,β-unsaturated esters via C–H activation is described, which provides an expedient access to fused β-lactams in one-step operation with high efficiency and good functional group tolerance. Of note, both ketimines and aldimines are amenable to this transformation. Mechanistic studies have identified a five-membered azamanganacycle as the key reaction intermediate.

关键词： C-H键不饱和酯酮亚胺锰催化双环活化反应中间体耐受性

Recent advances of rhenium separation and enrichment in China： Industrial processes and laboratory trials

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Chinese Chemical Letters 2018年第3期29卷 345-352页

作者： Yin wang congyang wang Radiochemistry Laboratory School of Nuclear Science and Technology Lanzhou University Lanzhou 730000 China Key Laboratory of Special Function Materials and Structure Design Ministry of Education Lanzhou 730000 China Beijing National Laboratory for Molecular Sciences CA5 Key Laboratory of Moiecular Recognition and Function CAS Research/Education Center for Excellence in Molecular Sciences Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China University of Chinese Academy of Sciences Beijing 100049 China

China is a major producer of rhenium, which is widely used in aerospace technologies （as superalloy） and petrochemical industries （as catalyst）. There is a gap between the demand and fact for the enrichment of rhenium, due to its rather small content （10-9） in the earth＇s crust. Also, there is no available single occurrence of mineral rhenium. Instead, the rhenium is associated with either molybdenum or copper （of up to 0.2% in content） as a by-product in metallurgical industry. This makes the separation of rhenium from the major mineral metals a challenge. The recent progresses in the separation and enrichment of rhenium were reviewed in this paper, especially, the advances in China. The details of varied separation methods used either in laboratories or factories, such as ion-exchange, solvent extraction, separation utilizing extractive resins, liquid membrane, or novel materials, etc., were elaborated. Comparison of the different methods was disclosed and an outlook on the rhenium chemistry and industry in the future was brought forward.

关键词： Rhenium Separation Enrichment Ion exchange Solvent extraction

Direct silylation reactions of inert C-H bonds via transition metal catalysis

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Science China Chemistry 2015年第8期58卷 1266-1279页

作者： Yunhui Yang congyang wang Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Molecular Recognition and Function Institute of Chemistry Chinese Academy of Sciences

In the past thirty years,transition metal catalyzed silylation of inert C–H bonds has attracted intensive attention due to the importance and wide use of organosilicon compounds.In this review,the silylation reactions of inert C–H bonds catalyzed by transition metal complexes of Ir,Rh,Ru,Pt,Pd,Ni,and Sc,and the strategies utilized to access the site-selective C–H silylation products have been summarized.Furthermore,the mechanisms of C–H silylation reactions have been discussed briefly.

关键词：过渡金属催化硅烷基化反应 C-H键惰性过渡金属配合物硅烷化反应有机硅化合物 Ru