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ECD spectrometric methods for detecting the enantioselective enzymatic hydrolysis of racemic 3-acetoxy-4-phenyl-β-lactam

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Chinese Chemical Letters 2012年第10期23卷 1197-1200页

作者： Xiang Zhang Li Li yi kang si Da Li yin Beijing Key Laboratory of Active Substances Discovery and Druggability Evaluation Institute of Materia MedicaChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100050China

（-）-（3R, 4S）-3-Acetoxy-4-phenylazetidin-2-one （（-）-1） was the key intermediate for preparing optical C-13 side-chain moiety in partial synthesis of docetaxel and paclitaxel. It can be successfully prepared via enantioselective hydrolysis of racemic esters （（-4-）-1） catalyzed by bacterial lipases, but the current reaction evaluation method is tedious and inconvenient. Electronic circular dichroism （ECD） has been widely applied in the stereochemical study of chiral compounds. In this paper, a rapid ECD spectroscopic method has been proposed and established to detect the transformation directly. The absolute configurations of lipase-catalyzed hydrolysis products have also been confirmed by quantum-chemical calculation using time-dependent density functional theory （TDDFT） methodology.

关键词： ECD spectroscopy Evaluation method Absolute configuration Time-dependent density functional theory

Absolute configuration of Buagafuran:An experimental and theoretical electronic circular dichroism study

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Chinese Chemical Letters 2013年第6期24卷 500-502页

作者： Li Li Chun Li yi-kang si Da-Li yin Beijing Key Laboratory of Active Substances Discovery and Druggability Evaluation Institute of Materia MedicaChinese Academy of Medical Sciences & Peking Union Medical College

Buagafuran is a novel drug candidate derived from natural *** absolute configuration has been confirmed by electronic circular dichroism combined with modern quantum-chemical calculation using time-dependent density functional *** predicted UV absorbance peak is underestimated by several nanometers compared with the experimental *** applicability of empirical rule for the C=C-C-O system in Buagafuran has also been *** results show that electronic circular dichroism could be a useful tool for the absolute configuration assignment of chiral drugs,especially for the oily or semisolid substances,whose crystal structures are impossible to obtain.

关键词： Electronic circular dichroism Chiral drugs Absolute configuration Time-dependent density functional theory

Using Nuclear Magnetic Resonance and MS/MS Spectroscopy for the Identification of Brodimoprim Metabolites in Rat Urine

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Chinese Chemical Letters 2001年第6期12卷 513-516页

作者： Chun YANG Wen yi HE Li Jun LI Rui Ming XU Shou Ren ZHANG Zeper ABLIZ yi kang si Institute of Materia Medica Chinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100050

Eight metabolites of brodimoprim (BDP) in rat urine were detected by NMR and EsiMS/MS. They were demethyl-BDP glucuronide, demethyl-BDP sulfurate, demethyl-BDP glucuronide sulfurate, alpha -hydroxyl-BDP, alpha -hydroxyl-BDP glucuronide, BDP sulfurate, N-oxide-BDP sulfurate, and alpha -hydroxyl-N-oxide-BDP sulfurate. All the sulfurates are reported for the first time.

关键词： Nuclear magnetic resonance spectroscopy MS/MS spectroscopy metabolites brodimoprim

Revisit the empirical rules for a,β-unsaturated γ-lactones using quantum-chemical calculations

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Revisit the empirical rules for a,β-unsaturated γ-lactones...

NOX4 exacerbates Parkinson's disease pathology by promoting neuronal ferroptosis and neuroinflammation

中国化学会第十届全国天然有机化学学术会议

作者： Li Li Bei-Bei Yang yi-kang si Institute of Materia Medica Chinese Academy of Medical Sciences & Peking Union of Medical College

The C=C-C-O group ofa,b-unsaturatedg-lactone is an inherently symmetrical chromophore,but becomes optically active in an asymmetrical *** chirala,b-unsaturatedg-lactones often appear in the chemical structures of natural products and synthetic intermediates,their stereochemistry attracted great interests of organic *** circular dichroism

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Neural Regeneration Research 2025年第7期20卷 2038-2052页

作者： Zhihao Lin Changzhou ying Xiaoli si Naijia Xue yi Liu Ran Zheng ying Chen Jiali Pu Baorong Zhang Department of Neurology The Second Affiliated HospitalZhejiang University School of MedicineHangzhouZhejiang ProvinceChina

Parkinson's disease is primarily caused by the loss of dopaminergic neurons in the substantia nigra ***,a novel form of regulated cell death characterized by iron accumulation and lipid peroxidation,plays a vital role in the death of dopaminergic ***,the molecular mechanisms underlying ferroptosis in dopaminergic neurons have not yet been completely *** oxidase 4 is related to oxidative stress,however,whether it regulates dopaminergic neuronal ferroptosis remains *** aim of this study was to determine whether NADPH oxidase 4 is involved in dopaminergic neuronal ferroptosis,and if so,by what *** found that the transcriptional regulator activating transcription factor 3 increased NADPH oxidase 4 expression in dopaminergic neurons and astrocytes in an 1-methyl-4-phenyl-1,2,3,6 tetrahydropyridine-induced Parkinson's disease *** oxidase 4 inhibition improved the behavioral impairments observed in the Parkinson's disease model animals and reduced the death of dopaminergic ***,NADPH oxidase 4 inhibition reduced lipid peroxidation and iron accumulation in the substantia nigra of the Parkinson's disease model ***,we found that NADPH oxidase 4 interacted with activated protein kinase Cαto prevent ferroptosis of dopaminergic ***,by lowering the astrocytic lipocalin-2 expression,NADPH oxidase 4 inhibition reduced 1-methyl-4-phenyl-1,2,3,6 tetrahydropyridine-induced *** findings demonstrate that NADPH oxidase 4 promotes ferroptosis of dopaminergic neurons and neuroinflammation,which contribute to dopaminergic neuron death,suggesting that NADPH oxidase 4 is a possible therapeutic target for Parkinson's disease.

关键词： dopaminergic neuron ferroptosis NADPH oxidase 4(NOX4) neuroinflammation Parkinson's disease

Dissipation-free approach for realizing non-Hermitian dynamics in a superconducting circuit

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Science China(Physics,Mechanics & Astronomy) 2025年

作者： yi-Hao kang Yang Xiao Yu Wang Qi-Ping Su Chui-Ping Yang School of Physics Hangzhou Normal University Fujian Key Laboratory of Quantum Information and Quantum Optics Fuzhou University Department of Physics Fuzhou University

Non-Hermitian dynamics exhibits a wealth of surprising and potentially useful phenomena. However, it is typically realized by coupling a system with thermal reservoirs, which makes the system suffer from thermal fluctuations associated with the dissipation. Here, we propose a dissipation-free approach to realize non-Hermitian dynamics using a superconducting circuit composed of two resonators and a superconducting qutrit. The non-Hermiticity arises in the dynamical matrix for the evolution of the two resonators in the Heisenberg picture, via a photon-number non-conserved dynamics. The energy spectrum of the non-Hermitian dynamical matrix can be retrieved by measuring the state of the two resonators, and a phase transition of the energy spectrum can be observed by varying the control parameters. In the realization of the non-Hermitian dynamics, the dissipation of the system and the post-selection are not required. Thus, the approach is implemented in a deterministic way, and the reservoir-induced noise is suppressed. Numerical simulations indicate that the energy spectrum of the non-Hermitian dynamical matrix obtained via the measurement of the resonators is in accordance with the theoretical prediction. Moreover, we demonstrate the parity discrimination for the state of two four-level qudits as an application, exhibiting the potential of the non-Hermitian dynamics in the field of quantum measurement. This work opens a new avenue for the realization of non-Hermitian dynamics and may have a significant implication in exploring the non-Hermitian phenomena.

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Homologous CoS2 interface with directed electron transfer and strong chloridion repulsion for efficient seawater oxidation

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Science China Chemistry 2025年

作者： Yuan Tian Jiang-Bo Chen Jie ying Ge Tian Yu-Xuan Xiao yi Lu si-Ming Wu Wei Geng Ling Shen Xiao-Yu Yang State Key Laboratory of Advanced Technology for Materials Synthesis and Processing and School of Materials Science and Engineering and Shenzhen Research Institute & Laoshan Laboratory Wuhan University of Technology School of Chemical Engineering and Technology Sun Yat-Sen University National Energy Key Laboratory for New Hydrogen-Ammonia Energy Technologies Foshan Xianhu Laboratory

Seawater electrolysis is a highly promising method to produce high energy density hydrogen,especially in dry areas that have scarce freshwater ***,application of seawater electrolysis is confronted by two major problems associated with catalysts employed for the anodic oxygen evolution reaction （OER） including the competitive hypochlorite evolution reaction（HCER） and strong chloridion （Cl–） triggered *** studies aimed at overcoming these problems,a facile method has been developed to synthesize a homologous CoS2heterojunction as an OER *** to a difference in work functions at the interface and increased electron density,this material has directed electron transfer and strong chloridion repulsion properties,*** have shown that CoS2achieves low overpotentials of 289 and 322 mV at 10 mA cm-2current density in respective alkaline （1 M KOH） and alkaline simulated seawater ***,the outstanding stability of CoS2is reflected in a negligible decline in activity during promotion of the OER for 100 *** of density functional theory calculations reveal that the homologous CoS2heterojunction promotes directed electron transport for optimizing adsorption/desorption of reactive species and heightens the Cl-adsorption energy for strongly repulsing Cl-,phenomena that enhance OER performance in alkaline simulated seawater.

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加州大学洛杉矶分校“本科生发起教育”项目的实施与特点

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黑龙江高教研究 2025年第2期43卷 81-87页

作者：高芳祎王思诗华东理工大学上海200237

美国加州大学洛杉矶分校(UCLA)的“本科生发起教育”(UsiE)项目,是一项选择优秀的高年级本科生,让他们在导师指导下,围绕自己选择的某个主题开设课程并开展教学的革新项目。该项目从学生倡议提出到最终成为UCLA的永久教育项目,经过严格... 详细信息

美国加州大学洛杉矶分校(UCLA)的“本科生发起教育”(UsiE)项目,是一项选择优秀的高年级本科生,让他们在导师指导下,围绕自己选择的某个主题开设课程并开展教学的革新项目。该项目从学生倡议提出到最终成为UCLA的永久教育项目,经过严格论证和长期试验,历时十年之久,是比较成功的“以学生为中心”课程革新项目。从“学生中心生态系统”(SCE)视角审视,UsiE的成功离不开其在课程权力分享、教学支持提供、项目质量保障、管理制度融入、政策文化重塑等方面表现出的多维统一特点。我国在“以学生为中心”的一流本科课程建设过程中,应注意整合兼顾课程开发、教学支持、质量保障、管理制度和政策文化等层面系统化推进课程革新,特别要加强学生赋权,强化组织治理,注重质量监测,推动文化再造,使以学生为中心的变革不停留在理念口号、角色转变、关系重建等单一要素或维度,而是成为一种弥散于整个大学机体的文化精神。

关键词：本科生发起教育学生中心生态系统特点

Progress in in vitro culture and gene editing of porcine spermatogonial stem cells

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Zoological Research 2019年第5期40卷 343-348页

作者： yi-Zhuo Sun si-Tong Liu Xiao-Meng Li kang Zou Germline Stem Cells and Microenvironment Lab College of Animal Science and Technology Nanjing Agricultural University Nanjing Jiangsu 210095 China College of Life Sciences Jilin University Changchun Jilin 130012 China Key Laboratory of Molecular Epigenetics of MOE Institute of Genetics and Cytology Northeast Normal University Changchun Jilin 130024 China

Research on in vitro culture and gene editing of domestic spermatogonial stem cells (SSCs) is of considerable interest but remains a challenging issue in animal science. In recent years, some progress on the isolation, purification, and genetic manipulation of porcine SSCs has been reported. Here, we summarize the characteristics of porcine SSCs as well current advances in their in vitro culture, potential usage, and genetic manipulation. Furthermore, we discuss the current application of gene editing in pig cloning technology. Collectively, this commentary aims to summarize the progress made and obstacles encountered in porcine SSC research to better serve animal husbandry, improve livestock fecundity, and enhance potential clinical use.

关键词： Progress vitro culture stem cells