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Catalytic Asymmetric Addition and Telomerization of Butadiene with Enamine Intermediates

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CCS Chemistry 2022年第7期4卷 2267-2275页

作者： Yaning Wang Jie Zhang Chang You xueling mi Sanzhong Luo Key Laboratory for Molecular Recognition and Function Institute of ChemistryChinese Academy of SciencesBeijing 100190 School of Chemical Science University of Chinese Academy of SciencesBeijing 100190 College of Chemistry Beijing Normal UniversityBeijing 100875 Center of Basic Molecular Science(CBMS) Department of ChemistryTsinghua UniversityBeijing 100084

Herein,we report tunable asymmetric addition and telomerization of butadiene by synergistic chiral primary amine/achiral palladium catalysis.A selection of different achiral phosphine ligand in concert with the chiral primary amine-trifluoromethanesulfonic acid(TfOH)conjugates enables both chemo-and enantioselective control of the coupling with butadiene.Bidentate[(oxydi-2,1-phenylene)-bis-(diphenylphosphine)](DPEPhos)ligand led to 1,4-addition adduct whereas monodentate(p-Tol)3P ligand gave the telomerization product.A range ofα-branchedβ-ketoesters and aldehydes could be applied to afford allylation or telomerization products bearing allcarbon quaternary centers at high efficiency and good chemo-,regio-,and stereoselectivities.

关键词： synergetic catalysis chiral primary amine addition telomerization palladium butadiene

SF5-Containing Heterocycles Synthesis:One-pot C-H Activated Cyclization from SF5-Anilines

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SF5-Containing Heterocycles Synthesis:One-pot C-H Activated ...

中国化学会第30届学术年会-第四十五分会：物理有机

作者： xueling mi Jing Chen Lijin Xu College of Chemistry Beijing Normal University Department of Chemistry Renmin University of China

Due to its unique structural and chemo/physical properties such as high lipophilicity,strong electron-withdrawing effect and steric bulkness,pentafluorosulfanyl(SF)moiety has beenregarded as a new generation of fluorine substituent and SF5-containing compounds have received increasing attention in material sciences as well as in medicinal applications.Despite having been prepared almost half a century ago,synthetic chemistry with organic sulfur pentafluorides has been remained largely underdeveloped due to the difficulties in accessing SF5-containing building

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SF5-Containing Heterocycles Synthesis: One-pot C-H Activated Cyclization from SF5-Anilines

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SF5-Containing Heterocycles Synthesis: One-pot C-H Activated...

中国化学会第九届全国有机化学学术会议

作者： xueling mi Jing Chen Lijin Xu College of Chemistry Beijing Normal University Department of Chemistry Renmin University of China

关键词：

The Origin of Enantio- and N/O-selectivity in Primary Amine Catalyzed Hydroxyamination of 1,3-Dicarbonyls with In-situ formed Nitrosocarbonyls

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The Origin of Enantio- and N/O-selectivity in Primary Amine ...

手性中国2014学术研讨会

作者： Long Zhang Changming Xu xueling mi Sanzhong Luo Beijing National Laboratory for Molecular Sciences(BNLMS) CAS Key Laboratory for Molecular Recognition and FunctionInstitute of Chemistrythe Chinese Academy of Sciences College of Chemistry Beijing Normal University

＜正＞Chemoselective control of N-and O-selection is an intriguing issue in nitroso chemistry.1 Recently,we reported an unprecedented asymmetric a-amination ofβ-ketocarbonyls by coupling of catalytic enamine carbonyls with in-situ generated carbonyl nitroso2.The process is enabled by a simple chiral primary-tertiary diamine derived from tert-Leucine.The reaction features high chemoselectivity,excellent enantioselectivity for a broad range of substrates.A

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Chiral pyrrolidine-azole conjugates: Simple and efficient asymmetric organocatalysts for michael addition to nitrostyrenes

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Chinese Science Bulletin 2010年第17期55卷 1735-1741页

作者： ZHANG Long XU Hui mi xueling LUO SanZhong CHENG Jin-Pei Department of Chentistry and State Key Laboratory of Elemento-organic Chemistry Nankai University Tianjin 300071 China Beijing National Laboratory for Molecular Sciences (BNLMS) CAS Key Laboratory of Molecular Recognition and Function Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China

Simple pyrrolidine-azole conjugates have been synthesized and found to be efficient catalysts for asymmetric michael addition to nitrostyrenes. The identified optimal catalysts, pyrrolidine-azoles 2, 8 and 13, could catalyze the asymmetric michael addition of a range of michael donors and nitrostyrenes in high yields (up to 99%) and excellent stereoselectivities (up to 99:1 dr and 97% ee).

关键词：不对称michael加成有机催化剂吡咯烷迈克尔复合物三氮唑手性高效催化剂

Catalytic Asymmetric Mannich Reaction with N-Carbamoyl Imine Surrogates of Formaldehyde and Glyoxylate

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Catalytic Asymmetric Mannich Reaction with N-Carbamoyl Imine...

中国化学会第十二届全国物理有机化学学术会议

作者： Yang'en You Long Zhang Linfeng Cui xueling mi Sanzhong Luo College of Chemistry Beijing Normal University

＜正＞N,O-acetals （NOAcs） have been developed as bench stable surrogates for N-carbamoyl formaldehyde and glyoxylate imines in asymmetric Mannich reactions.The NOAcs can be directly utilized in the chiral primary amine catalyzed Mannich reactions of both acyclic and cyclicβ-ketocarbonyls with high yields and excellent

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基于标准化指数的中国东北地区复合高温干旱事件时空变化特征分析

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河北省科学院学报 2024年第1期41卷 1-10页

作者：张雪玲朱美琪李颖辽宁师范大学地理科学学院辽宁大连116029

干旱和极端高温事件会对人类社会和生态环境造成严重影响,当两种极端事件同时发生时会造成更大的威胁。本文利用1961-2020年网格化的月值降水和气温数据,计算标准化降水蒸散发指数(SPEI)和标准化温度指数(STI),在界定复合事件的基础上... 详细信息

干旱和极端高温事件会对人类社会和生态环境造成严重影响,当两种极端事件同时发生时会造成更大的威胁。本文利用1961-2020年网格化的月值降水和气温数据,计算标准化降水蒸散发指数(SPEI)和标准化温度指数(STI),在界定复合事件的基础上分析不同干热阈值下中国东北地区复合高温干旱事件的时空演变特征,探究复合事件的空间相关性。结果表明,中国东北地区复合高温干旱事件发生频率在空间分布表现出东部及东南部低、西部及西北部高的特点;分析复合事件的历史演变发现mi-mi以0.02/a速率上升,且在20世纪90年代之后大幅度升高;总体复合事件影响面积呈现显著的上升趋势,幅度为1.02%/a,不同类型复合事件影响面积均显著升高且在20世纪90年代大幅度上升达到峰值;复合事件的高频区聚集在西部和西北部,低频区聚集在东南部及东部。研究成果可为东北地区防灾减灾、农业规划、水资源配置等提供参考。

关键词：复合高温干旱事件时空特征空间相关性 SPEI STI

表达荧光素酶的胰腺癌细胞系的建立及其在免疫细胞杀伤效力检测中的应用

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中华微生物学和免疫学杂志 2024年第1期44卷 58-66页

作者：梁谦许崇凤李国亚张丽霞吴雪伶周小雅孟淑芳中国食品药品检定研究院生物制品检定研究所细胞资源保藏研究中心北京102600

目的构建表达报告基因荧光素酶和肿瘤相关抗原间皮素(mesothelin,MSLN)基因的胰腺癌细胞系,评估其作为靶细胞在评价免疫细胞的肿瘤杀伤效力中的应用。方法构建表达荧光素酶、MSLN基因的慢病毒载体,包装慢病毒,感染胰腺癌细胞系,抗生素... 详细信息

目的构建表达报告基因荧光素酶和肿瘤相关抗原间皮素(mesothelin,MSLN)基因的胰腺癌细胞系,评估其作为靶细胞在评价免疫细胞的肿瘤杀伤效力中的应用。方法构建表达荧光素酶、MSLN基因的慢病毒载体,包装慢病毒,感染胰腺癌细胞系,抗生素筛选后,有限稀释法获得单细胞克隆,并验证目的基因的稳定表达。实时无标记细胞分析(real-time cell analysis,RTCA)和荧光素酶活性检测方法体外检测免疫细胞对肿瘤细胞的杀伤效力。将构建的细胞系接种B-NDG小鼠建立表达荧光素酶的胰腺癌肿瘤模型,利用活体成像技术检测荧光素酶表达水平,监测小鼠体内胰腺癌肿瘤生长情况。在胰腺癌小鼠模型中验证嵌合抗原受体T(chimeric antigen receptor T,CAR-T)细胞的肿瘤杀伤能力。结果本研究建立了稳定表达荧光素酶和MSLN基因的胰腺癌细胞系panc-1-luc、panc-1-luc-MSLN和capan-2-luc细胞。3种细胞的报告基因表达水平较高,与细胞数量呈正相关,panc-1-luc-MSLN细胞的MSLN阳性率达95.6%。体外肿瘤细胞杀伤试验结果表明MSLN-CAR-T细胞能特异性杀伤MSLN抗原阳性的panc-1-luc-MSLN细胞和capan-2-luc细胞,最小杀伤率分别为(70.00±18.19)%和(57.00±5.29)%,而对MSLN阴性的panc-1-luc细胞无杀伤作用。RTCA结果显示MSLN-CAR-T细胞对构建的3种胰腺癌细胞均有杀伤能力,最小杀伤率分别为(56.33±7.64)%、(93.00±2.65)%和(26.33±28.15)%;NK-92mi细胞对靶细胞的杀伤不受MSLN限制。免疫缺陷小鼠胰腺癌模型结果显示,体内杀伤效力与体外荧光素酶活性检测结果一致。体内外试验证明,检测靶细胞荧光素酶表达活性,可以反映免疫细胞对靶细胞的杀伤效力。结论本研究建立了稳定表达荧光素酶的多株胰腺癌单克隆细胞系,可用于体内外免疫治疗产品肿瘤杀伤效力的研究评价。

关键词：胰腺癌荧光素酶间皮素活体成像技术免疫治疗

Fabrication and Characterization of Gecko-inspired Dry Adhesion, Superhydrophobicity and Wet Self-cleaning Surfaces

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Journal of Bionic Engineering 2016年第1期13卷 132-142页

作者： Yongchao Zhang Shuxin Qu Xiang Cheng xueling Gao Xia Guo Key Lab of Advanced Technologies of Materials Ministry of Education School of Materials Science and Engineering Southwest Jiaotong University Chengdu 610031 China The Hong Kong Polytechnic University Department of Rehabilitation Sciences Kowloon Hong Kong 999077 China

In this study, gecko-inspired polydimethylsiloxane （PDMS） microfiber surfaces were fabricated by combining Inductively Coupled Plasma （ICP） and micro-mold casting. The effect of roughness and surface energy of counterface on the adhesion of gecko-inspired microflber surfaces and its superhydrophobicity and wet self-cleaning were studied. The adhesion of gecko-inspired microfiber surfaces depended on the roughness of the eounterfaces due to the influences of contact area and interlocking mechanism. SEM images of interfaces between counterfaces with different roughness and gecko-inspired mi- crofiber surfaces revealed the matched and dis-matched contact directly. The gecko-inspired microfiber surface got the larger adhesive force from the higher surface energy counterface, which is consisted with Johnson-Kendall-Roberts （JKR） theory. The smaller dimension and lower duty ratio of microfibers on PDMS resulted in the increasing of Water Contact Angle （WCA） and the decreasing of Sliding Angle （SA） compared to those of smooth PDMS. Particularly, sample P-8-28-20 had the biggest WCA （155°） and SA （7°）, which displayed the superhydrophobicity and the best wet self-cleaning efficiency in all samples. The present studies showed that the roughness and surface energy of counterface both affected the adhesion of gecko-inspired microfiber surfaces. The smaller dimension and lower duty ratio of microfibers on PDMS endowed it with the superhydro- phobicity and the wet self-cleaning abilities.

关键词： gecko-inspired microfiber polydimethylsiloxane surfaces surface properties counterface superhydrophobicity wet self-cleaning