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Chinese Journal of Chemistry 2021年第4期39卷 859-865页

作者： Dong Yi Linying He zhongyu qi Zhijie Zhang Mengshun Li Ji Lu Jun Wei Xi Du qiang Fu Siping Wei Department of Medicinal Chemistry School of PharmacySouthwest Medical UniversityLuzhouSichuan 646000China People’s Hospital of Xinjin District ChengduSichuan 611430China School of Pharmacy Binzhou Medical UniversityYantaiShandong 264003China Central Nervous System Drug Key Laboratory of Sichuan Province LuzhouSichuan 646000Chino

Main observation and conclusion Alkoxy radical-mediated carbon-carbon bond cleavages have emerged as a powerful strategy to complement traditional ionic-type ***,carbon-carbon cleavage reaction triggered by alkoxy radical intermediate derived from the combination of alkyl radical and dioxygen,is scarce and ***,we report alkoxy radical,which was generated from alkyl radical and dioxygen,mediated selective cleavage of unstrained carbon-carbon bond for the oxysulfonylation of 1,1-disubstituted alkenes,providing facile access to a variety of valuableβ-keto *** experiments indicated alkoxy radical intermediate that underwent subsequent regioselectiveβ-scission might be involved in the reaction and preliminary computational studies were conducted to provide a detailed explanation on the regioselectivity of the C-C bond ***,the strategy was successfully applied for constructing uneasily obtained architecturally intriguing molecules.

关键词： Carbon-carbon cleavage Alkoxy radical Copper-catalyzed 1,1-Disubstituted alkenes Sulfonyl hydrazides

Metal-Free Photocatalytic[4+2]Annulation of Acrylamides with 2-Benzyl-2-bromocarbonyls to Assemble Tetralin-1-carboxamides

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Chinese Journal of Chemistry 2024年第2期42卷 157-163页

作者： Weicai Li Lu Tan Yijun Chen Rui Liu zhongyu qi Shixuan Yuan Zhanwen Huang Siping Wei Xi Du Dong Yi Nuclear Medicine and Molecular Imaging Key Laboratory of Sichuan Province School of PharmacySouthwest Medical UniversityLuzhouSichuan 646000China Department of Chemistry School of Basic Medical ScienceSouthwest Medical UniversityLuzhouSichuan 646000China Department of Pharmacy Affiliated HospitalSouthwest Medical UniversityLuzhouSichuan 646000China

Tetralin-1-carboxamides are frequently incorporated in myriad medicinally important ***,their existing synthetic routes not only suffer from some drawbacks such as tedious procedures,harsh reaction conditions,narrow substrate scope,low yields,and environmental problems,but are also based upon the elaboration of uneasily available non-linear tetralin ***,we describe a metal-and additive-free visible light-induced[4+2]annulation of two simple linear starting materials,namely acrylamides and 2-benzyl-2-bromocarbonyls,through a cascade C(sp^(3))-Br/C(sp^(2))-H bond cleavage,double C-C bond formation,and aromatization *** developed protocol provides a convenient,efficient,and green approach to a variety of tetralin-1-carboxamide derivatives with good functional group ***,the resulting products could also undergo the Licl-mediated mono-decarboxylative cyclization process to further furnish the architecturally novel bridged polycyclic imides with excellentcis-diastereoselectivities.

关键词： Annulation Metal-free Photoredox catalysis Tetralin-1-carboxamide Cyclic imides Synthetic methods C-C coupling Radical reactions Reaction mechanisms

负荷控制器在PX提纯蒸馏塔平衡控制中的应用

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仪器仪表用户 2015年第3期22卷 56-57,25页

作者：齐忠宇中国石油工程建设公司大连设计分公司辽宁大连116023

本文介绍了负荷控制在1000000t/年芳烃联合装置吸附分离单元的PX提纯蒸馏塔中的成功应用。通过工艺过程分析、热力平衡计算和控制方案实施等方面作应用分析。

关键词：负荷控制器热量平衡重沸器

关于黑龙江省600MW机组定子接地保护时限定值的探讨

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黑龙江电力 1999年第4期21卷 25-26页

作者：齐忠玉郭宏伟王凤蛟黑龙江省电力职工大学大庆石油管理局龙凤热电厂哈尔滨发电厂

通过对黑龙江省６００ＭＷ发电机定子接地保护的分析，并结合国内外发电机定子接地保护选取的原则，对６００ＭＷ发电机定子接地保护减小时限定值的可能性进行了讨论。

关键词：发电机定子接地保护时限

Oxidation reactivity of 1,2-bis(2,4,6-tribromophenoxy)ethane(BTBPE)by CompoundⅠmodel of cytochrome P450s

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Journal of Environmental Sciences 2017年第12期29卷 11-21页

作者： zhongyu Wang Zhiqiang Fu qi Yu Jingwen Chen Key Laboratory of Industrial Ecology and Environmental Engineering(MOE) School of Environmental Science and TechnologyDalian University of TechnologyDalian 116024China

Alternative brominated flame retardants（BFRs） have become prevalent as a consequence of restrictions on the use of polybrominated diphenyl ethers（PBDEs）. For risk assessment of these alternatives, knowledge of their metabolism via cytochrome P450 enzymes is *** have previously proved that density functional theory（DFT） is able to predict the metabolism of PBDEs by revealing the molecular mechanisms. In the current study, the reactivity of 1,2-bis（2,4,6-tribromophenoxy）ethane and structurally similar chemicals with the Compound I model representing the active site of P450 enzymes was investigated. The DFT calculations delineated reaction pathways which lead to reasonable explanations for products that were detected by wet experiments, meanwhile intermediates which cannot be determined were also proposed. Results showed that alkyl hydrogen abstraction will lead to bis（2,4,6-tribromophenoxy）ethanol, which may undergo hydrolysis yielding2,4,6-tribromophenol, a neurotoxic compound. In addition, a general pattern of oxidation reactivity regarding the 2,4,6-tribromophenyl moiety was observed among several model compounds. Our study has provided insights for convenient evaluation of the metabolism of other structurally similar BFRs.

关键词： 1 2-Bis(2 4 6-tribromophenoxy)ethane(BTBPE) Alternative brominated flame retardants Metabolic reactivity P450 Compound Ⅰ

In-depth understanding of transport behavior of sulfided nano zerovalent iron/reduced graphene oxide@guar gum slurry: Stability and mobility

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Journal of Environmental Sciences 2024年第10期144卷 1-14页

作者： Yuheng Ma Wenhui You Zijiang Yang zhongyu Ren qi Jing Faculty of Architecture Civil and Transportation EngineeringBeijing University of TechnologyBeijing 100124China

Nanoscale zero-valent iron(NZVI),which has the advantages of small particle size,large specific surface area,and high reactivity,is often injected into contaminated aquifers in the form of ***,the prone to passivation and agglomeration as well as poor stability andmobility of NZVI limit the further application of this technology in ***,sulfided NZVI loaded on reduced graphene oxide(S-NZVI/rGO)and guar gum(GG)with shearthinning properties as stabilizers were used to synthesize S-NZVI/rGO@GG ***,TEM,and FT-IR confirmed that the dispersion and anti-passivation of NZVI were optimized in the coupled *** stability and mobility of the slurry were improved by increasing the GG concentration,enhancing the pH,and decreasing the ionic strength and the presence of Ca^(2+)ions,respectively.A modified advection-dispersion equation(ADE)was used to simulate the transport experiments considering the strain and physicochemical deposition/***,colloidal filtration theory(CFT)demonstrated that Brownian motion plays a dominant role in themigration of S-NZVI/rGO@GG slurry,and the maximummigration distance can be increased by appropriately increasing the injection ***-Derjaguin-Landau-Verwey-Overbeek(XDLVO)theory showed that the excellent stability and migration of S-NZVI/rGO@GG slurry mainly came from the GG spatial *** study has important implications for the field injection of S-NZVI/rGO@GG *** to the injection parameters,the injection range of S-NZVI/rGO@GG slurry is effectively controlled,which lays the foundation for the promotion of application in actual fields.

关键词： S-NZVI rGO Guar gum Transport Stability

中药通过中性粒细胞胞外诱捕网治疗新型冠状病毒感染研究进展

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实用中医内科杂志 2023年第12期37卷 66-70页

作者：高雷齐中玉关运鹏白长川朱英大连医科大学中西医结合学院辽宁大连116044 大连医科大学附属第一医院辽宁大连116011 大连市中医医院辽宁大连116013

2019年12月底由严重急性呼吸综合征冠状病毒2(Severe acute respiratory syndrome coronavirus 2,SARS-CoV-2)感染引起的新型冠状病毒感染(Corona Virus Disease 2019,COVID-19)爆发,目前仍威胁人类健康。中西医结合治疗COVID-19取得了不错的临床效果。尽管SARS-COV-2疫苗使用以后,疫情得到了一定的控制但是仍不断有变异株的产生,极大的制约了疫苗的作用。为了更好地解决目前仍在困扰人类的COVID-19,探究中医药治疗COVID-19的科学机制仍然至关重要。中性粒细胞胞外诱捕网(Neutrophils extracellular traps,NETs)在COVID-19的疾病发展中起到了十分重要的推动作用,是疾病预后不良的指征之一。病原微生物、活化的血细胞、部分有活性的细胞因子、循环DNA等均是促进NETs形成的因素,NETs对机体的影响具有两面性,一方面是帮助机体杀灭侵入机体的病原微生物,另一方面如果NETs在体内产生过量,会引起广泛组织炎性反应、免疫血栓形成、肺纤维化、肝纤维化、急性肾损伤、心力衰竭等脏器病变。中药可以通过抗病毒、清除氧自由基、抑制中性粒细胞活化、抑制血小板活化、抑制中性粒细胞炎性小体的形成等多途径多靶点降低体内NETs水平治疗COVID-19并改善预后。文章主要综述中医药通过降低循环中NETs水平治疗COVID-19的最新研究进展,为开发中医药价值提供参考。

关键词：中性粒细胞胞外诱捕网新型冠状病毒感染中医药中西医结合严重急性呼吸综合征冠状病毒2

手性环氧醇及其磷酸酯化物的合成及抗肿瘤活性筛选

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西南医科大学学报 2022年第1期45卷 39-43页

作者：张迪陈平王舒戚仲钰詹小燕杜曦西南医科大学药学院药物化学教研室泸州646000 遂宁市中心医院药学部遂宁629000 天府中药城管理委员会彭州611900 西南医科大学基础医学院化学教研室泸州646000

目的寻找基于Sharpless不对称环氧化反应的手性环氧醇及其磷酸酯化物合成的优化条件。方法以烯丙基醇为起始原料,合成炔基、苯基和烷基(3b~8b)取代的手性环氧醇。再用氯磷酸二苯酯处理上述产物,得到相应的磷酸酯化物(3c~5c,8c)。采用1H ... 详细信息

目的寻找基于Sharpless不对称环氧化反应的手性环氧醇及其磷酸酯化物合成的优化条件。方法以烯丙基醇为起始原料,合成炔基、苯基和烷基(3b~8b)取代的手性环氧醇。再用氯磷酸二苯酯处理上述产物,得到相应的磷酸酯化物(3c~5c,8c)。采用1H NMR,13C NMR,31P NMR和MS表征化合物结构,手性HPLC测定产物的对映异构过量(ee)值,并对所得化合物的抗肿瘤活性进行初筛。结果合成了10种不同取代的手性环氧醇及其磷酸酯化物,活性实验结果显示部分化合物对Hela细胞、231细胞和HepG2细胞增殖有一定的抑制作用。结论建立了优化的Sharpless不对称环氧化反应条件及手性环氧醇的磷酸酯化反应条件,对拓展Sharpless法的应用有重要参考意义。

关键词：手性环氧醇磷酸酯化 Hela细胞 231细胞 HepG2细胞

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放射治疗组织补偿物的制作及应用

甘肃医药 2020年第8期39卷 745-746,751页

作者：杜瑞琴郭晴杨进福祁中昱贾怀琳张东强甘肃省肿瘤医院甘肃兰州730050

目的:设计制作合适的组织补偿物,改善病变靶区内人体不平坦部位的剂量均匀度。方法:以与人体密度相似的热塑膜、液体石蜡为材料,分别针对突出皮肤表面的病灶和凹陷部位的病灶设计制作组织补偿物,研究其用于临床的可行性。结果:对人体不... 详细信息

目的:设计制作合适的组织补偿物,改善病变靶区内人体不平坦部位的剂量均匀度。方法:以与人体密度相似的热塑膜、液体石蜡为材料,分别针对突出皮肤表面的病灶和凹陷部位的病灶设计制作组织补偿物,研究其用于临床的可行性。结果:对人体不平坦体表应用自制的热塑膜、液体石蜡等组织补偿物,按需制作成合适的形状、厚度,可提高皮肤及浅层组织放射治疗的吸收剂量。结论:该组织补偿物制作方法简单,个体化程度高,摆位重复性好,值得临床推广应用。

关键词：放射治疗组织补偿物热塑膜、液体石蜡

Structural basis of Zika virus helicase in recognizing its substrates

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Protein & Cell 2016年第8期7卷 562-570页

作者： Hongliang Tian Xiaoyun Ji Xiaoyun Yang Zhongxin Zhang zuoku Lu Kailin Yang Cheng Chen qi Zhao Heng Chi zhongyu Mu Wei Xie Zefang Wang Huiqiang Lou Haitao Yang Zihe Rao School of Life Sciences Tianjin University Tianjin 300072 China Tianjin Intemational Joint Academy of Biotechnology and Medicine Tianjin 300457 China The State Key Laboratory of Pharmaceutical Biotechnology School of Life Sciences Nanjing University Nanjing 210023 China State Key Laboratory of Agro-Biotechnology College of Biological Sciences China Agricultural University Beijing 100193 China College of Life Sciences Nankai University Tianjin 300071 China Cleveland Clinic Lemer College of Medicine of Case Western Reserve University Cleveland OH 44195 USA Department of Molecular Biophysics and Biochemistry Yale University New Haven CT 06520 USA

The recent explosive outbreak of Zika virus （ZlKV） infection has been reported in South and Central America and the Caribbean. Neonatal microcephaly associated with ZIKV infection has already caused a public health emergency of international concern. No specific vaccines or drugs are currently available to treat ZIKV infection. The ZIKV helicase, which plays a pivotal role in viral RNA replication, is an attractive tar- get for therapy. We determined the crystal structures of ZIKV helicase-ATP-Mnz＋ and ZlKV helicase-RNA. This is the first structure of any flavivirus helicase bound to ATP. Comparisons with related flavivirus helicases have shown that although the critical P-loop in the active site has variable conformations among different species, it adopts an identical mode to recognize ATPIMn2＋. The structure of ZlKV helicase-RNA has revealed that upon RNA binding, rotations of the motor domains can cause significant conformational changes. Strikingly, although ZlKV and dengue virus （DENV） apo-helicases share conserved residues for RNA binding, their different manners of motor domain rotations result in distinct individual modes for RNA recognition. It suggests that flavivirus helicases could have evolved a conserved engine to convert chemical energy from nucleoside triphosphate to mechanical energy for RNA unwinding, but different motor domain rotations result in variable RNA recognition modes to adapt to individual viral replication.

关键词： Zika virus helicase ATP crystal structure,flavivirus