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Synthesis of two mono-deoxy β-cyclodextrin derivatives as useful tools for confirming DIBAL-H promoted bis-de-O-methylation mechanism

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Chinese Chemical Letters 2012年第12期23卷 1315-1318页

作者： Su Long Xiao De Min Zhou Ming Yang Fei Yu Li He Zhang Pierre sinay Yong Min Zhang State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical SciencesPeking University Institut Parisien de Chimie Moleculaire UMR CNRS 7201Universite Pierre et Marie Curie-Paris 64 Place Jussieu Institute for Interdisciplinary Research Jianghan UniversityWuhan Economic and Technological Development Zone

Diisobutylaluminium hydride （DIBAL-H） promotes secondary rim regioselective bis-de-O-methylation of permethylated β- cyclodextrin （β-CD） to give diol 2. To gain an insight into the mechanism of this remarkable regioselective behavior, two corresponding permethylated β-CDs with an alcohol function at either 2- or 3-position were synthesized in our previous study. As a step further to this work, the two compounds were subjected to deoxygenation reaction with tributyltin hydride in the present of 2,2＇- azobisisobutyronitrile affording the corresponding 2- and 3-deoxy permethylated β-CD derivatives （19 and 16）. The structures of these two compounds were characterized by 1D and 2D NMR and HRMS. Compounds 16 and 19 were unable to react with DIBAL- H which suggests that O-2A and O-3B are necessary for DIBAL-H promoted bis-de-O-methylation reaction of permethylated β-CD.

关键词： Cyclodextrin (CD) DIBAL-H Deoxy Synthesis Mechanism

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Transient decrease in sound tolerance levels following hearing deprivation in normal-hearing subjects

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Journal of Otology 2022年第4期17卷 232-238页

作者： Eleazar Grateron Tricia Scaglione Shriya Airen Stefania Goncalves sinay a.ceb.llos David Baguley Juan A.Chiossone Fundacion Venezolana de Otología Clinical Research GroupVenezuela University of Miami Department of OtolaryngologyUSA University of Nottingham Hearing ScienceUK

Objective:To determine the circadian influence on sound sensitivity produced by temporal hearing deprivation in healthy normal human ***:Participants underwent bilateral earplugging before completion of anthropometry,the author's developed questionnaire,the Hamilton Anxiety and Depression Inventory,pure tone audiometry(PTA),stapedial reflex thresholds(SRT),distortion products otoacoustic emissions input/output(DPOAE-I/O),and uncomfortable loudness levels(ULLs).Afterward,the participants were randomly divided into group A,starting at 8:00 *** finishing at 8:00 p.m.,and group B,starting at 4:00 *** ending at 4:00 *** cortisol levels and audiological test results were obtained at the beginning and end of the session and 24-h free urinary cortisol levels were *** sample:Thirty healthy ***:PTA was 2.68 and 3.33 dB HL in groups A and B,respectively,with no statistical difference between *** were significantly lower in group A compared to group B,with an average of 8.1 dB SPL in group A and 3.3 dB SPL in group B(p<0.0001).A SRT shift was observed in group A,with no difference in group B,and a night shift in DPOAE-I/O in group ***:Reduced loudness tolerance is demonstrated during daytime hearing deprivation in contrast to nighttime;this may be due to increased central gain in the awake cortex.

关键词： Hyperacusis Central gain Hearing deprivation

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Assessment of Global Fatigue in Multiple Sclerosis: A Spanish Language Version of the CGI and PGI Fatigue Scales

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Neuroscience & Medicine 2013年第3期4卷 140-144页

作者： Steven D. Targum Pablo Richly Vladimiro sinay Daniel Goldberg-Zimring Facundo Manes Clintara LLC Boston USA Institute of Neurosciences at Favaloro University Buenos Aires Argentina

Background: Fatigue is often identified as weakness following muscular exertion in patients with multiple sclerosis (MS) but may be associated with other physical, cognitive and emotional symptoms. Objective: To develop a Spanish language global impression of fatigue scales to evaluate symptoms of fatigue distinct from a particular disease. Methods: 50 ambulatory patients with MS attending a clinical institute in Argentina consented to participate in this reliability study. The Spanish language version of the Clinical and Patient Global Impressions of Fatigue (CGI-S-F and PGI-S-F) instruments were administered with the Massachusetts General Hospital cognitive and physical functioning questionnaire (MGH-CPFQ). Results: The CGI-S-F and PGI-S-F scores were well correlated with each other (p < 0.00005). The mean CGI-S for fatigue was 2.28 ± 1.07 (SD) and PGI-S for fatigue was 2.30 ± 1.16 (p = ns) reflecting borderline to mild perception of fatigue. The total MGH-CPFQ was 16.68 ± 4.32. Both CGI-S-F and PGI-S-F measures were correlated with the MGH-CPFQ: CGI-Severity (r = 0.632;p < 0.00005);PGI-Severity (r = 0.717;p Conclusions: In this study, the Spanish language versions of the CGI-S-F and PGI-S-F were reliable measures in an MS population and can be useful and easily applied metrics in a busy clinical practice.

关键词： Reliability Multiple Sclerosis Spanish Global Assessment Fatigue Psychometrics Treatment Response

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高压和高温条件下金刚石催化合成过程的结构状况

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人工晶体学报 1982年第4期 31-33页

作者： A.A.Yдceb 莫文裔

在文献~〔1〕中我们曾指出,金刚石稳定区内、组分为 KtC(Kt 为触媒)的过渡触煤复合物之产生,会使金刚石与过渡触媒合成物之间界面处的相表面能量显著降低,并使金刚石形成过程的速度提高。下面我们来详细论述此现象的结构状况。触媒通常... 详细信息

在文献~〔1〕中我们曾指出,金刚石稳定区内、组分为 KtC(Kt 为触媒)的过渡触煤复合物之产生,会使金刚石与过渡触媒合成物之间界面处的相表面能量显著降低,并使金刚石形成过程的速度提高。下面我们来详细论述此现象的结构状况。触媒通常在金刚石合成之前先行溶解。触媒流洒在石墨颗粒表面(具有触媒活性的物质可充分湿润石墨~〔2〕,同时触媒原子即扩散到石墨的层间空间中,从而生成金刚石复合物~〔3〕。在高压与接近触媒熔融温度的条件下,

关键词：金刚石晶体触媒碳原子石墨层催化合成

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DIBAL-H促全甲基化-a-环糊精进一步脱甲基的研究(英文)

DIBAL-H促全甲基化-a-环糊精进一步脱甲基的研究(英文)

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2010施慧达杯第十届全国青年药学工作者最新科研成果交流会

作者：肖苏龙周德敏 SOLLOGOUB Matthieu sinay Pierre 张勇民杨铭北京大学药学院天然药物及仿生药物国家重点实验室

以DIBAL-H作"化学手术刀(chemical scalpel)",系统的研究其促全甲基化α-环糊精脱甲基作用,共获得四个新的全甲基化α-环糊精脱甲基衍生物,为进一步探讨DIBAL-H促全甲基化环糊精脱甲基的作用机理提供了依据。

关键词： α-环糊精 DIBAL-H 脱甲基

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