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host-guest complexes of cucubit[8]uril with phenanthrolines and some methyl derivatives

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Science China Chemistry 2005年第4期48卷 305-314页

作者： DAY Anthony I Chemistry Discipline School of Physical Environmental and Mathematical SciencesUniversity College UNSWAustralian Defence Force AcademyCanberraACT2600 Australia

The host-guest relationship between cucurbit[8]uril,phenanthrolines and some methyl substituted 1,10-phenanthrolines has been investigated by using 1h NMR spectroscopy and fluorescence spectroscopy.The results showed that phenanthrolines as molecular guests bind in the cavity and portal of cucurbit[8]uril in a ratio of 2:1 (guest to host).The phenanthroline isomers 1,10-,1,7-and 4,7-showed red shifts between 47 and 108 nm and pronounced in-creases in fluorescent intensity.These same isomers produced inclusion complexes with cucur-bit[8]uril which had moderate to fast exchange rates on the 1h NMR time scale.The methyl substituted 1,10-phenanthrolines studied gave stable inclusion complexes in a ratio of 2:1 which showed slow exchange rates.These guests formed p-p stacked pairs which were cavity bound but also partly protruded from only one portal forming unsymmetrical host-guest complexes.In addition,these p-p stacked pairs formed orientation isomers within the confines of the cucur-bit[8]uril cavity.

关键词： 1h NMR technique, fluorescence, cucurbituril, phenanthroline, host-guest, orientation isomers.

3.0T 1h magnetic resonance spectroscopy for assessment ofsteatosis in patients with chronic hepatitis C

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World Journal of Gastroenterology 2015年第21期21卷 6736-6744页

作者： Qian Zhang hui-Mao Zhang Wen-Qian Qi Yong-Gui Zhang Ping Zhao Jian Jiao Jiang-Bin Wang Chun-Yu Zhang Department of Gastroenterology China Japan Union Hospital Affiliated to Jilin University Department of Radiology 1~(st) Hospital Affiliated to Jilin University

AIM To investigate the utility of 1h magneticresonance spectroscopy （1h MRS） as a noninvasivetest for steatosis in patients infected with hepatitis Cvirus.METhODS： Ninety patients with chronic hepatitisC and pathology data underwent 3.0T 1h MRS, andthe results of MRS and pathological analysis werecompared.RESULTS： This group of patients included 26 peoplewith mild fatty liver （28.89%）, 16 people withmoderate fatty liver （17.78%）, 18 people with severefatty liver （20.0%）, and 30 people without fatty liver（33.33%）. The water peak was near 4.7 parts permillion （ppm）, and the lipid peak was near 1.3 ppm.Analysis of variance revealed that differences in thelipid peak, the area under the lipid peak, ratio of thelipid peak to the water peak, and ratio of the areaunder the lipid peak to the area under the waterpeak were statistically significant among the groups.Specifically, as the severity of fatty liver increased, thevalue of each index increased correspondingly. In thepairwise comparisons, the mean lipid peak, area underthe lipid peak, ratio of the lipid peak to the waterpeak, and ratio of the area under the lipid peak to thearea under the water peak were significantly differentbetween the no fatty liver and moderate fatty liver groups, whereas no differences were noted betweenthe severe fatty liver group and the mild or moderatefatty liver group. Area under the ROC curve （AUC） ofarea ratio in lipid and water and ratio in lipid and waterin the no fatty liver group to mild fatty liver group, mildfatty liver group to moderate fatty liver group, andmoderate fatty liver disease group to severe fatty livergroup, were 0.705, 0.900, and 0.975, respectively.CONCLUSION： 1h MRS is a noninvasive techniquethat can be used to provide information on the effectof liver steatosis on hepatic metabolic processes. Thisstudy indicates that the 1h MRS can be used as anindicator of steatosis in patients with chronic hepatitis C.

关键词： 1h Magnetic resonance spectroscopy hepatitisC Antiviral therapy

Microscopic structures of ionic liquids 1-ethyl-3-methylimidazolium tetrafluoroborate in water probed by the relative chemical shift

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Science China Chemistry 2010年第7期53卷 1561-1565页

作者： XU YingJie GAO Yan ZhANG LiQun YAO Jia WANG CongMin LI haoRan Department of Chemistry Zhejiang UniversityHangzhou 310027China Department of Chemistry Shaoxing UniversityShaoxing 312000China

The relative chemical shifts (△δ) △δwere put forward to investigate the microscopic structure of 1-ethyl-3-methyl-imidazolium tetrafluoroborate (EmimBF4) during the dilution process with water.The concentration-dependent △δ(C2)h-(C4)h,△δ(C2)h-(C5)h and △δ(C4)h-(C5)h were analyzed.The results reveal that the variations of the microscopic structures of three aromatic protons are inconsistent.The strength of the h-bond between water and three aromatic protons follows the order:(C2)h···O > (C4)h···O > (C5)h···O.The concentration-dependent △δ(C6)h-(C7)h and △δ(C6)h-(C8)h indicate the formation of the h-bonds of (Calkyl)h···O is impossible,and more water is located around (C6)h than around (C7)h or (C8)h.The concentration-dependent △δ(C2)h-(C4)h and △δ(C2)h-(C5)h both increase rapidly when xwater > 0.9 or so,suggesting the ionic pairs of EmimBF4 are dissociated rapidly.The turning points of concentration-dependent △δ(C2)h-(C4)h and △δ(C2)h-(C5)h indicate that some physical properties of the EmimBF4/water mixtures also change at the corresponding concentration point.The microscopic structures of EmimBF4 in water could be clearly detected by the relative chemical shifts.

关键词： ionic liquids 1h NMR microscopic structure relative chemical shifts 1-ethyl-3-methyl-imidazolium tetrafluoroborate

~1h MAS NMR spectra of kao-linite/formamide intercalation compound

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Chinese Science Bulletin 2002年第6期47卷 504-508页

作者： Linjiang Wang Daqing Wu Peng Yuan Zhiwei Chen Zhong Chen Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China State Key Laboratory for Physical Chemistry of Solid Surfaces Department of Chemistry Xiamen University Xiamen China College of Chemistry and Chemical Engineering Xiamen China

The high spinning speed 1h magic angle spinning nuclear magnetic resonance (1h MAS NMR) technique was employed to distinguish the two groups of surface hy-droxyls of kaolinite and investigate the intercalation mechanism of kaolinite/formamide compound. The proton chemical shifts of the inner hydroxyl and inner surface hydroxyl of kaolinte are in the range of δ-1.3--0.9 and δ 2.4-3.0 respectively. After formamide intercalation three proton peaks were detected. The proton peak of the inner surface hydrox-yls of the intercalation compound shifts to high-field with δ2.3-2.7, which is assigned to the formation of the hydrogen bond between the inner surface hydroxyl and formamide carbonyl group. Whereas, the proton peak of the inner hydroxyl shifts to δ-0.3 toward low-field, that is attributed to van der Waal’s effect between the inner hydroxyl proton and the amino group proton of the formamide which may be keyed into the ditrigonal hole of the kaolinite. The third peak, additional proton peak, is in the

关键词： kaolinite surface hydroxyl formamide intercalation mechanism 1h MAS NMR.

~1h MAS NMR spectra of hy-droxyl species on diatomite surface

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Chinese Science Bulletin 2001年第13期46卷 1118-1121页

作者： Yuan Peng Wu Daqing Chen Zhong Chen Zhiwei Lin Zhongyu Diao Guiyi Peng Jinlian Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China State Key Laboratory for Physical Chemistry of Solid Surfaces College of Chemistry and Chemical Engineering Xiamen University Xiamen China College of Chemistry and Chemical Engineering Xiamen University Xiamen China

high spinning speed 1h magic-angle spinning nuclear magnetic resonance (1h MAS NMR) was used to detect surface hydroxyl groups of diatomite, which include isolated hydroxyl groups and hydrogen-bonded hydroxyl groups, and water adsorbed on diatomite surface that include pore water and hydrogen-bonded water. The corresponding proton chemical shifts of above species are ca. 2.0, 6.0-7.1, 4.9 and 3.0 respectively. Accompanied by thermal treatment temperature ascending, the pore water and hydrogen-bonded water are desorbed successively. As a result, the relative intensities of the peaks assigned to protons of isolated hydroxyl groups and hydrogen-bonded hydroxyl groups increase gradually and reach their maxima at 1000℃. After 1100℃ calcination, the hydroxyl groups that classified to strongly hydrogen-bonded ones and the isolated hydroxyl groups condense basically. But some weakly hydrogen-bonded hydroxyl groups may still persist in the micro-pores.

关键词： diatomite surface hydroxyl groups 1h MAS NMR thermal treatment.

host-guest complexes of a water soluble cucurbit[6]uril derivative with some dications of 1,ω-alkyldipyridines:~1h NMR and X-ray structures

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Science China Chemistry 2009年第4期52卷 475-482页

作者： XIAO Xin ZhANG YunQian ZhU QianJiang XUE SaiFeng TAO Zhu Key Laboratory of Macrocyclic and Supramolecular Chemistry of Guizhou Province Guizhou UniversityGuiyang 550025China Institute of Applied Chemistry Guizhou UniversityGuiyang 550025China

Interactions between a symmetrical tetramethyl-substituted cucurbit[6]uril (host:TMeQ[6]) and 1,ω-alkylenedipyridine (ω = 2,4,6,8,10) dicationic guests were investigated using 1h NMR spectroscopy and single crystal X-ray crystallography. In these inclusion complexes,combined cavity and portal binding in TMeQ[6] were observed,and the length of the bridged alkylene was found to play an important role not only in balancing the overall hydrophilic/hydrophobic interaction between the host and the guest,but also in defining the structure of the resulting inclusion complexes. For the guest 1,2-ethylenedipyridine (Edpy),TMeQ[6] includes a positively charged pyridine ring of Edpy to form an unsymmetrical inclusion complex; for the guest 1,4-butylenedipyridine (Bdpy),TMeQ[6] includes a positively charged pyridine ring of Bdpy,but the different competitive interactions in and between the related inclusion complexes could lead to a fast exchange between the hosts and guests. For the guests with longer bridge chains,such as 1,6-hexamethylenedipyridine (hdpy) or 1,8-octylenedipyridine (Odpy),a stable pseudorotaxane inclusion complex is formed by combining the hydrophobic cavity and the outer portal dipoleion interactions. however,for 1,10-decatylenedipyridine (Ddpy),the two TMeQ[6] host molecules include the two end pyridine rings of Ddpy and form a dumbbell inclusion complex.

关键词： symmetrical tetramethyl-substituted cucurbituril 1 ω-alkylenedipyridine (ω = 2 4 6 8 10) dicationic guests host-guest complex 1h NMR spectroscopy single crystal X-ray crystallography

Interaction Between Cytochrome c and [Ptdien]^(2+)

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Chinese Science Bulletin 1994年第23期39卷 1973-1979页

作者：江丽娟姚亦明朱德煦唐雯霞 State Key Laboratory of Coordination Chemistry Coordination Chemistry Institute Nanjing University Nanjing 210093 PRC

Recently, intramolecular long distance electron transfer has received much attention and chemists are attempting to elucidate the factors that control the rates of metalloprotein electron transfer reactions. One impor... 详细信息

关键词： cytochrome c [Ptdien]2+ modified protein 1h NMR spectrum UV-vis spectrum.

基于~1h NMR代谢组学方法的糖尿病溃疡组织代谢特征和病理机制分析

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化学学报 2011年第19期69卷 2265-2271页

作者：谢丽云宋才勇娄依依徐志张美玲董柏君高红昌李校堃温州医学院药学院温州325035 上海交通大学医学院附属仁济医院泌尿科上海200127

糖尿病溃疡是临床上导致患者截肢的最主要原因,应用基于1h NMR的代谢组学方法研究了链脲佐菌素(STZ)诱导的SD糖尿病大鼠溃疡组织的代谢轮廓,同时结合组织病理和生化分析,阐述了糖尿病溃疡组织的代谢特征和病理机制.结果表明,糖尿病大鼠... 详细信息

糖尿病溃疡是临床上导致患者截肢的最主要原因,应用基于1h NMR的代谢组学方法研究了链脲佐菌素(STZ)诱导的SD糖尿病大鼠溃疡组织的代谢轮廓,同时结合组织病理和生化分析,阐述了糖尿病溃疡组织的代谢特征和病理机制.结果表明,糖尿病大鼠在溃疡组织愈合过程中的成纤维细胞增殖和毛细血管增生都明显弱于对照组;代谢组学分析的散点图表明糖尿病溃疡组和对照组在代谢模式上明显分开,不同愈合时间的糖尿病溃疡组在代谢模式上明显分开;载荷图表明糖尿病溃疡组相对于对照组,亮氨酸、异亮氨酸、丙氨酸、柠檬酸、胆碱和甜菜碱等代谢成分含量降低;而乳酸、醋酸、丙酮酸、肌酸、牛磺酸和甘氨酸等代谢成分含量上升.代谢组学提示的代谢物变化表明糖尿病溃疡组织的三羧酸循环被抑制,能量代谢平衡被破坏,溃疡组织可能通过增加无氧酵解和肌酸代谢来维持自身的能量平衡,并自我修复创伤的皮肤组织.本工作的研究有望为糖尿病溃疡的深入认识和治疗方案选择提供参考.

关键词：糖尿病溃疡 1h NMR 病理机制皮肤组织

基于^1h NMR代谢组学和偏最小二乘法的小柴胡汤证判别研究

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药学学报 2015年第8期50卷 1032-1037页

作者：邢婕原曙春孙慧敏范玛莉李震宇秦雪梅山西大学中医药现代研究中心山西太原030006 山西大学化学化工学院山西太原030006 山西省荣军医院山西太原030031

本文以临床观察选取的小柴胡汤证典型病例为研究对象,采用1h NMR代谢组学技术对小柴胡汤证患者与健康受试者尿液进行对比分析,从尿液核磁图谱中指认出内源性代谢物34种。正交偏最小二乘法-判别分析(OPLS-DA)显示,小柴胡汤证患者与健康... 详细信息

本文以临床观察选取的小柴胡汤证典型病例为研究对象,采用1h NMR代谢组学技术对小柴胡汤证患者与健康受试者尿液进行对比分析,从尿液核磁图谱中指认出内源性代谢物34种。正交偏最小二乘法-判别分析(OPLS-DA)显示,小柴胡汤证患者与健康受试者尿液中的代谢物可明显区分,说明小柴胡汤证患者体内代谢物轮廓发生了明显变化。结合S-plot散点图和VIP值找到15种差异代谢物,其中患者尿液中浓度升高的代谢物有亮氨酸、甲酸、甘氨酸、马尿酸、尿嘧啶,降低的有苏氨酸、2-羟基异丁酸、乙酰胺、2-氧化戊二酸、柠檬酸、二甲胺、丙二酸、甜菜碱、氧化三甲胺、苯乙酰甘氨酸、尿苷。这些代谢物涉及肠道微生物平衡、能量代谢和氨基酸代谢通路,与小柴胡汤证主证具有一定的相关性。应用偏最小二乘法建立小柴胡汤证的数学预测模型,该模型可准确判别小柴胡汤证患者。本研究为小柴胡汤证的客观诊断和合理用药奠定了实验基础。

关键词：小柴胡汤证 PLS分析代谢组学 1h NMR