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Design and Synthesis of 1,4-Dihydropyridine and Cinnamic Acid Esters and Their Antioxidant Properties

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Chemical Research in Chinese Universities 2016年第4期32卷 594-599页

作者： GAO Yang WANG Bowei GAO Shang ZHANG Ruhui YANG Chunying SUN Zheng LIU Zhihui School of Stomatology Capital Medical University Beijing 100050 P. R. China The Second Hospital of Jilin University Changchun 130021 P. R. China School of Stomatology Jilin University Changchun 130021 P. R. China

In this study, cinnamic acid derivatives with pyridine ring were synthesized via Hantzsch reaction in order to expand conjugation system and their antioxidant abilities were tested. According to the evaluation results of their antioxidant properties, compounds 2 and 3 have similar antioxidant activity to prevent DNA from ＊OH- and Cu2＋/GSH induced oxidation, demonstrating that 1,4-dihydropyridine and pyridine nucleus exhibit good resistance to oxidation while the substituents have little effect. In the meantime, the AAPH-induced oxidative DNA damage [AAPH=2,2＇-azobis（2-methylpropionamidine）dihydrochloride] and trapping ABTS＋＊ test show that N--H bond and large conjugation systems are the pivotal parts to improve the activities of antioxidant.

关键词： Cinnamic acid 1,4-Dihydropyridine free radical Oxidation Antioxidant DNA

Oxidative damage of primary cultured hippocampal neurons Does androgen have an antagonistic effect?

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Neural Regeneration Research 2010年第5期5卷 358-363页

作者： Zhaohui Li Zhiping Cai Huixian Cui Jinsong Zhu Sha Li Guosheng Xie Lei Xue Department of Neurosurgery Second Affiliated Hospital of Hebei Medical University Shijiazhuang 050000 Hebei Province China Department of Human Anatomy Hebei Medical University Shijiazhuang 050017 Hebei Province China Department of Anatomy Hebei University Basic Medical College Baoding 071000 Hebei Province China

BACKGROUND： Evidence illustrates that androgen has a neuroprotective role. However, whether androgen also has the protective effect on hippocampal neurons during free radical mediated injury remains unclear. OBJECTIVE： To investigate the neuroprotective effect of androgen on hippocampal neurons during free radical damage. DESIGN, TIME AND SETTING： A controlled in vitro experiment was performed at the Department of Human Anatomy, Cell Culture Lab, and Neuroendocrinology Lab, Basic Medical School, Hebei Medical University from February to June 2009. MATERIALS： Testosterone was provided by Tianjin Jinyao Amino Acid Company, China. METHODS： Primary cultured neurons from 24 Sprague Dawley rats were randomly assigned into four groups： control, H202, testosterone, and testosterone （pre-added） plus H2O2 groups. MAIN OUTCOME MEASURES： The positive cell ratio of microtubule associated protein-Ⅱ and neuron specific enolase was determined by immunocytochemistry. Neuronal morphology was observed by hematoxylin-eosin staining and Nissl staining. Cell vitality and viability were determined using an inverted phase contrast microscope. The content of nitric oxide synthase, malondialdehyde, and superoxide dismutase were measured with a spectrophotometer. RESULTS： As compared with the control group, cell vitality and viability, and superoxide dismutase level were significantly decreased in the H202 group （P 〈 0.05）, while nitric oxide synthase and malondialdehyde levels were significantly increased （P 〈 0.05）. Neuronal vitality and viability as well as superoxide dismutase level in the testosterone plus H2O2 group were significantly greater than in the H2O2 group （P 〈 0.05）, and nitric oxide synthase and malondialdehyde levels were significantly less than in the H2O2 group （P〈 0.05）. CONCLUSION： Androgen partially reversed H2O2-induced neuronal damage and protected neurons.

关键词： androgen primary cultured hippocampal neuron free radical nitric oxide synthase superoxide dismutase malondialdehyde oxidative damage

Understanding the Initial Decomposition Pathways of the n-Alkane/Nitroalkane Binary Mixture

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Chinese Journal of Chemistry 2013年第8期31卷 1087-1094页

作者： Yulei Guan Ying Zhang Chunhai Yi Bolun Yang Department of Chemical Engineering State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong University Xi'an Shannxi 710049 China

Addition of nitroalkanes into n-alkanes can lower the activation barriers of free-radical production and acceler- ate the decomposition of n-alkanes at relatively low temperatures. Four initial decomposition mechanisms of the n-butane/nitroethane binary mixture were proposed for the promoting effect and considered theoretically at the B3LYP, BB1K, BMK, MPW1K, and M06-2X levels with MG3S basis set. Energetics above was compared to high-level CBS-QB3 and G4 calculations. Calculated results confirm the feasibility of the four initial decomposition pathways：（I） the C--NO2 bond rupture of nitroethane to produce ethyl and .NO2, （II） HONO elimination from nitroethane followed by decomposition to .OH and .NO, （1II） rearrangement of nitroethane to ethyl nitrite which further dissociates into CH3CH20. and .NO, and （IV） direct hydrogen-abstraction ofnitroethane with n-butane.

关键词： free radical initial decomposition mechanism computational chemistry hydrogen-abstraction bimol-ecular

Design and Synthesis of 3-Triazolo-coumarins and Their Applications in Scavenging radicals and Protecting DNA

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Chemical Research in Chinese Universities 2015年第4期31卷 526-533页

作者： LIU Zhihui WANG Yingnan SUN Jingbo YANG Yang LIU Qingwen LIU Zaiqun SONG Zhiguang Hospital of Stomatology Jilin University Changchun 130021 P R. China Department of Organic Chemistry College of Chemistry Jilin University Changchun 130012 P 1L China

In this study, we synthesized a series of 3-triazolo-coumarins and evaluated their antioxidant activities respectively by two methods： trapping 2,2＇-azinobis（3-ethylbenzothiazoline-6-sulfonate） cationic radical（ABTS＋＋） and oxidation of DNA which was induced by Cu2＋/glutathione（GSH）, ·OH and 2,2＇-azobis（2-amidinopropane hydrochloride）（AAPH）. Among the nine 3-triazolo-coumarins, compounds 6c and 6f-6i were synthesized for the first time, which exhibited the capability of terminating radical propagation-chains in oxidation of DNA induced by AAPH. In this study, we found that phenethylamine moiety, hydroxyl and ortho-methoxy are the key groups to en- hance the antioxidant activities of compounds.

关键词： 3-Triazolo-coumarin Coumarin free radical Oxidation Antioxidant DNA

Role of apoptosis-inducing factor in perinatal hypoxic-ischemic brain injury

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Neural Regeneration Research 2021年第2期16卷 205-213页

作者： Juan Rodriguez Tao Li Yiran Xu Yanyan Sun Changlian Zhu Center for Brain Repair and Rehabilitation Institute of Neuroscience and PhysiologySahlgrenska AcademyUniversity of GothenburgGothenburgSweden Henan Key Laboratory of Child Brain Injury Institute of Neuroscience and Third Affiliated Hospital of Zhengzhou UniversityZhengzhouHenan ProvinceChina Department of Anatomy School of Basic Medical ScienceZhengzhou UniversityZhengzhouHenan ProvinceChina Department of Women’s and Children’s Health Karolinska InstitutetStockholmSweden

Perinatal complications,such as asphyxia,can cause brain injuries that are often associated with subsequent neurological deficits,such as cerebral palsy or mental *** mechanisms of perinatal brain injury are not fully understood,but mitochondria play a prominent role not only due to their central function in metabolism but also because many proteins with apoptosis-related functions are located in the *** these proteins,apoptosis-inducing factor has already been shown to be an important factor involved in neuronal cell death upon hypoxia-ischemia,but a better understanding of the mechanisms behind these processes is required for the development of more effective treatments during the early stages of perinatal brain *** this review,we focus on the molecular mechanisms of hypoxic-ischemic encephalopathy,specifically on the importance of apoptosis-inducing *** relevance of apoptosis-inducing factor is based not only because it participates in the caspase-independent apoptotic pathway but also because it plays a crucial role in mitochondrial energetic functionality,especially with regard to the maintenance of electron transport during oxidative phosphorylation and in oxidative stress,acting as a free radical *** also discuss all the different apoptosis-inducing factor isoforms discovered,focusing especially on apoptosis-inducing factor 2,which is only expressed in the brain and the functions of which are starting now to be ***,we summarized the interaction of apoptosis-inducing factor with several proteins that are crucial for both apoptosis-inducing factor functions(prosurvival and pro-apoptotic)and that are highly important in order to develop promising therapeutic targets for improving outcomes after perinatal brain injury.

关键词： apoptosis apoptosis inducing factor asphyxia cell death free radical hypoxia-ischemia mitochondria neonates oxidative stress

Study and Application of Polarographic Catalytic Wave of Chlordiazepoxide in the Presence of Persulfate

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Chinese Journal of Chemistry 2002年第5期20卷 502-508页

作者： Guo, W Lin, H Liu, LM Guo, ZA Song, JF NW Univ Xian Dept Chem Xian 710069 Peoples R China Yuxi Normal Coll Dept Chem Yunnan 653100 Peoples R China

Polarographic catalytic wave of chlordiazepoxide in the presence of K 2S 2O 8 was studied in aqueous and DMF/H 2O mixed solutions. The results showed that a single reduction wave in alkaline medium was the reduction of the N=C bond in 1,2 position of chlordiazepoxide via an intermediate free radical in two one electron successive additions. When K 2S 2O 8 was present, the free radical of the N=C bond was oxidized to regenerate the original, producing a parallel catalytic wave of chlordiazepoxide. It was determined that the apparent rate constant k f of the oxidation reaction was 3.2×10 3 mol -1 ·L·s -1 . Using the catalytic wave the trace of chlordiazepoxide can be determined by linear potential scan polarography. In NH 3/NH 4Cl (pH 10.2±0.1, 0.12 mol/L)/K 2S 2O 8 (0.016 mol/L) supporting electrolyte, the second order derivative peak current of the catalytic wave was rectilinear to chlordiazepoxide concentration in the range of 3.20×10 -8 -1.60×10 -7 , 1.60×10 -7 -1.44×10 -6 and 1.44 ×10 -6 -1.44×10 -5 mol/L, respectively. The limit of detection was 9.0×10 -9 mol/L.

关键词： chlordiazepoxide persulfate polarographic catalytic wave free radical

Buyang Huanwu decoction enhances cell membrane fluidity in rats with cerebral ischemia/reperfusion

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Neural Regeneration Research 2012年第21期7卷 1605-1610页

作者： Chenxu Li Institute of Brain Sciences Department of Physiology Medical College Datong University Datong 037009 Shanxi Province China

After bilateral carotid artery occlusion for 30 minutes and reperfusion for 2 hours, distinct pathological changes presented in the cerebral cortex and cerebellum of rats. Compared with normal rats, nerve cell membrane fluidity significantly decreased in ischemia/reperfusion rats as detected by spin-labeling electron spin resonance, consistent with order parameter S and rotational correlation time TC measurements. Brain nerve cells from rats with ischemia/reperfusion injury were cultured with 1-100 mg/mL Buyang Huanwu decoction. Results showed that Buyang Huanwu decoction gradually increased membrane fluidity dose-dependently to normal levels, and eliminated hydroxide （OH＇） and superoxide （O2＇） free radicals dose-dependenUy. These findings suggest that Buyang Huanwu decoction can protect against cell membrane fluidity changes in rats with ischemia/ reperfusion injury by scavenging free radicals.

关键词： Buyang Huanwu decoction ischemia/reperfusion electron spin resonance cell membrane fluidity free radical brain neural regeneration

Water Role and Its Influence on Hydrogen Isotopic Composition of Natural Gas during Gas Generation

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Acta Geologica Sinica(English Edition) 2011年第5期85卷 1203-1210页

作者： Jijun LI Shuangfang LU Wei WU Haitao XUE Qingxia XU Jie GENG Yinghua YU College of Earth Sciences Northeast Petroleum University Daqing Heilongjiang 163318 China Luliang Operating District of Xinjiang Oilfield Company Karamay Xinjiang 834000 China Exploration and Development Research Institute Daqing Oilfield Company Ltd. Daqing Heilongjiang 163712 China

In order to discuss the role and influence of water during the generation of natural gas,the participation mechanism of water during the evolution of organic matter and its influences were *** addition,we carried out an anhydrous cracking experiment of oil extracted from the Feixianguan Formation source rock in a closed system,which led to the establishment of the kinetic models for describing carbon and hydrogen isotopic fractionation during gas generation from organic *** models were calibrated and then applied to the northeastern Sichuan *** combining a series of gas generation experiments from octadecane pyrolysis without water or with distilled water in varying mass proportions,several results were proved:(1) the hydrogen isotopic composition of natural gas becomes lighter with the participation of formation water;(2) we can quantitatively study the hydrogen isotopic fractionation with the kinetic model for describing carbon isotopic fractionation; (3) more abundant and reliable geological information can be obtained through the combined application of carbon and hydrogen isotopic indices.

关键词： natural gas formation water free radical carbonium ion carbon and hydrogen isotopic fractionation kinetics

STUDY OF GRAFT SITES IN EPOXY GRAFT COPOLYMERS BY QUANTUM CHEMISTRY CALCULATIONS

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Chinese Journal of Polymer Science 2009年第4期27卷 517-524页

作者：李效玉 College of Materials Science and Engineering Beijing University of Chemical Technology

Exploration and characterization of grafting productions by experimental methods are often cumbersome or sometimes ***,quantum chemistry calculations were performed to characterize the graft sites of epoxy *** to the Gibbs free energy criterion of the second law of thermodynamic,the reported graft sites were confirmed,and more important,some unreported graft sites were *** addition,method of increasing the number of graft sites was studied in this article.

关键词： Epoxy resin free radical Graft site