1,4-二取代苯基-3-酰氨基-2-吖啶酮类化合物的80兆~1H-NMR谱及构型研究

本文报道了在FT-80A NMR波谱仪上测定的22个新标题化合物的80兆~1H-NMR谱,进行了谱线归属,确定了该系列化合物均为顺式构型,讨论了不同溶剂对谱峰和化学位移的影响。     

二盐酸氟哌噻吨几何异构体的核磁共振研究

采用COSY、NOESY、HSQC、HMBC二维核磁共振技术，首次对二盐酸氟哌噻吨的两种几何异构体的^1H-NMR、^13C-NMR谱信号进行全归属。归属结果表明，二盐酸氟哌噻吨两种几何异构体的部分^1H-NMR、^13C-NMR谱数据差别较大，可作为区分两种异构体的一个指标。     

酚酞芳香酯环状二聚体核磁共振谱

报道了酚酞芳香酯环状二聚体核磁共振氢 和碳谱，通过与模型化合物标准谱图的比较以及化学位移取代基效应的计算，归属了其碳谱和氢谱峰。     

淮安市食管鳞癌患者血清~1 H NMR波谱初步研究

测试了30例正常人血清和60例淮安市食管鳞癌患者血清的氢核磁共振波谱.观察到正常人血清的共振峰主要集中在化学位移δH(ppm)1.00 ～5.00,构建了正常人血清的~1H NMR指纹图谱.同时将食管鳞癌患者血清1H NMR与正常人血清~1H NMR进行比较,发现食管鳞癌患者与正常人血清样品在δ_H 1.0 ～1.2 和δ_H 3.0 ～3.8(如δH 3.25、3.23、3.36、3.41、3.43)存在一定的差异波峰,即食管鳞癌的可能特征峰.表明借助于1H NMR特征峰有助于食管鳞癌的早期诊断.     

原位生成三苄氧基钇催化ε-己内酯可控开环聚合

本文研究了以烷基钇[Y(CH2SiMe3)3(THF)2]与苯甲醇原位反应生成的三苄氧基钇为引发剂的ε-己内酯(CL)可控开环聚合。研究结果表明,随着聚合体系中单体/引发剂摩尔比的增大,由1H-NMR计算和GPC测定得到的产物聚己内酯(PCL)的数均分子量均随之线性增加,且分子量分布(Mw/Mn =1.4～1.1)逐渐变窄;1H-NMR计算所得PCL的数均分子量与由单体/引发剂投料比计算得到的理论值一致,表明该体系催化的CL开环聚合具有很好的可控性。1H-NMR分析显示产物PCL的端基分别为苯甲醇酯和醇羟基,由此提出了可能的开环聚合机理。     

Determination of enantiomer separation factors by nuclear magnetic resonance spectroscopy and by chiral liquid chromatography

The equilibrium constants K+ and K- for formation of the diastereomeric complexes of the two enantiomers of O,O'-dibenzoyltartaric acid (DBTA) with the chiral selector N,N'-diallyltartardiamide bis-(4-tert.-butylbenzoate) (TBB) have been determined by 1H-NMR. The experiments were performed at different temperatures in CDCl3 or in cyclohexane-d12/2-propanol-d8 mixtures. The equilibrium constants from the 1H-NMR results have been compared with the retention factors (k') obtained from the chromatographic resolution of rac. DBTA on a Kromasil CHI-TBB column with the same solvents as mobile phases. A satisfactory correlation between the 1H-NMR data and the chromatographic data was found.     

基于~1H-NMR、~(31)P-NMR的三苯基膦三间磺酸钠定量分析研究

该文建立了三苯基膦三间磺酸钠(TPPTS)的核磁氢谱(~1H-NMR)、核磁磷谱(~(31)P-NMR)、定量分析方法。通过~1H-NMR、~(13)C-NMR、~(31)P-NMR并结合~1H-~1H COSY、~1H-~(13)C、~1H-~(13)C HMBC对TPPTS的氢原子、碳原子以及磷原子的化学位移进行归属;氢谱定量选用三■烷作内标、氘代N,N-二甲基甲酰胺(DMF-D_7)作溶剂,磷谱定量选用KH_2PO_4作内标、氘代水(D_2O-D_2)作溶剂,通过对混合体系中各自旋核纵向弛豫时间(T1)的测定,为弛豫延迟时间(D1)的合理设置提供依据。以上两种方法对体系中TPPTS的定量分析结果分别为(58.72±0.21)%、(58.51±0.21)%,测定结果一致性高、平行性好,且检测过程无需待测组分的标准品,能实现TPPTS含量的快速准确测定。     

Capillary electrophoretic separation of binaphthyl enantiomers with two polymeric chiral surfactants: 1H-nuclear magnetic resonance and fluorescence spectroscopy study

The use of the water-soluble polymeric chiral surfactants (PCS), sodium N-undecanoyl-L-valinate (poly-L-SUV) and sodium undecanoyl-L-isoleucinate (poly-L-SUI) as buffer additives in electrokinetic chromatography (EKC) afforded the separation of racemic mixtures of 2,2'-dihydroxy-1,1'-binaphthyl (BOH) and 1,1'-binaphthyl-2,2'-diyl hydrogen phosphate (BNP). The apparent binding constants of the PCS to the enantiomers of BNP and BOH were obtained through 1H-nuclear magnetic resonance (1H-NMR) titrations and fluorescence spectroscopy, respectively. The 1H-NMR titration studies show that the BNP enantiomers are localized in the hydrophobic micellar pockets of PCS and form complexes of a 1:1 stoichiometry. The binding constants of PCS of BOH were determined from a Benesi-Hildebrand treatment of the fluorescence data. The EKC data corroborate those of the binding constants, supporting the formation of inclusion complexes. A model rationalizing the chiral discrimination of the enantiomers of BNP is proposed based on the intermolecular interactions observed in 1H-NMR data.     

丙烯酸全氟烷基乙基酯嵌段共聚物的组成结构表征

含氟聚合物具有独特的性质 ,使其成为高分子材料领域中的特殊功能材料 .这类聚合物具有高表面活性、高热稳定性、高化学稳定性 ,及既憎水又憎油的“三高”、“两憎”特性[1] ,可用作织物拒水拒油整理剂、防污涂料、流平剂等 .然而含氟单体价格高昂 ,人们希望在满足性能要求的同时 ,尽量减少氟单体的用量 .利用分子设计方法 ,制备结构规整的嵌段共聚物无疑是一种有效的方法 .目前 ,文献中关于含氟嵌段共聚物的制备的方法有负离子聚合法[2 ] 、基团转移聚合法 (GTP) [3 ] 、正离子聚合法[4] 、引发 转移 终止法 (Iniferter) [5] ,以及近年…     

三氟乙氧基取代的吡啶衍生物的核磁氢谱及质谱研究

本文报道了三个由三氟乙氧基取代的氯代三氟甲基吡啶化合物的核磁共振氢谱及电子轰击质谱，结果表明，与乙氧基化合物相对照，在Ｈ－ＮＭＲ中，由于三氟甲基的强吸电子作用，其次甲基移向低场，并给出了一组具有较大偶合常数的四得峰。在ＥＩＭＳ中，均存在较多的架重排离子峰，其中Ｃ－Ｏ，Ｃ－Ｆ，Ｃ－ＣＦ３键断裂及失法ＣＯ形成的五元，四元含氮杂环离子是重要质谱特征。     

Metabolic fingerprinting of Ephedra species using 1H-NMR spectroscopy and principal component analysis

The metabolomic analysis of Ephedra species was performed using 1H-NMR spectroscopy and multivariate data analysis. A broad range of metabolites could be detected by 1H-NMR spectroscopy without any chromatographic separation. The principal component analysis used to reduce the huge data set obtained from the 1H-NMR spectra of the plant extracts clearly discriminated three different Ephedra species. The major differences in Ephedra sinica, Ephedra intermedia and Ephedra distachya var. distachya were found to be due to benzoic acid analogues in the aqueous fraction and ephedrine-type alkaloids in the organic fraction. Based on this metabolomic recognition, one of nine commercial Ephedra materials evaluated was shown to be a mixture of Ephedra species. This method will be a useful tool for chemotaxonomic analysis and authentification of Ephedra species including quality control of plant materials.     

二醋酸纤维素接枝聚己内酯的核磁共振表征

用^1H-NMR和^13C-NMR研究了二醋酸纤维素(CDA)和聚己内酯(PCL)的接枝共聚反应,确定了^1H-NMR和^13C-NMR谱中各谱峰的归属,为证明二醋酸纤维素和己内酯的接枝共聚反应提供了依据。     

1H-NMR Metabolomics as a Tool for Winemaking Monitoring

The chemical composition of wine is known to be influenced by multiple factors including some viticulture practices and winemaking processes. ¹H-NMR metabolomics has been successfully applied to the study of wine authenticity. In the present study, ¹H-NMR metabolomics in combination with multivariate analysis was applied to investigate the effects of grape maturity and enzyme and fining treatments on Cabernet Sauvignon wines. A total of forty wine metabolites were quantified. Three different stages of maturity were studied (under-maturity, maturity and over-maturity). Enzyme treatments were carried out using two pectolytic enzymes (E1 and E2). Finally, two proteinaceous fining treatments were compared (vegetable protein, fining F1; pea protein and PVPP, fining F2). The results show a clear difference between the three stages of maturity, with an impact on different classes of metabolites including amino acids, organic acids, sugars, phenolic compounds, alcohols and esters. A clear separation between enzymes E1 and E2 was observed. Both fining agents had a significant effect on metabolite concentrations. The results demonstrate that ¹H-NMR metabolomics provides a fast and robust approach to study the effect of winemaking processes on wine metabolites. These results support the interest to pursue the development of ¹H-NMR metabolomics to investigate the effects of winemaking on wine quality.     

二次加工柴油中烯烃的分析

采用溴价电子轰击质谱、核磁共报氢谱以及溴加成／场电离质谱等综合分析二次加工柴油中的燃烃。     

Synthesis and conformational properties of 2,6-bis-anilino-3-nitropyridines

The synthesis of 2,6-bis-anilino-3-nitropyridines that are alkylated or acylated at the anilino nitrogen atoms is described. These derivatives show characteristic differences in the 1H-NMR spectra compared with the unsubstituted parent compound. These differences are used to determine structure-conformation relationships of this type of compounds. The conclusions drawn from the 1H-NMR spectra in this respect are supported by X-ray crystallographic data and by 1H-NMR data of conformationally restricted analogues. Preliminary investigations indicate that these relationships can in principle be extended to other diarylamines.     

Analysis of nitrophenols and other polar nitroaromatic compounds in ammunition wastewater by high-field proton nuclear magnetic resonance (1H-NMR) spectroscopy and chromatographic methods

 It is shown that by using high-field proton nuclear magnetic resonance (¹H-NMR) spectroscopy it is possible, without prior separation, to analyse nitrophenols and other acidic nitroaromatic compounds in the “pH 2 extract” of ammunition wastewater. The ¹H-NMR chemical shifts data of a variety of reference compounds are presented. Two groundwater samples from the former ammunition plant in Elsnig (Saxony) were analysed by ¹H-NMR and also by chromatographic methods (GC/MS, HPLC). The results are compared and discussed. Received: 17 January 1996/Revised: 15 May 1996/Accepted: 17 May 1996     

Analysis of nitrophenols and other polar nitroaromatic compounds in ammunition wastewater by high-field proton nuclear magnetic resonance (1H-NMR) spectroscopy and chromatographic methods

 It is shown that by using high-field proton nuclear magnetic resonance (¹H-NMR) spectroscopy it is possible, without prior separation, to analyse nitrophenols and other acidic nitroaromatic compounds in the “pH 2 extract” of ammunition wastewater. The ¹H-NMR chemical shifts data of a variety of reference compounds are presented. Two groundwater samples from the former ammunition plant in Elsnig (Saxony) were analysed by ¹H-NMR and also by chromatographic methods (GC/MS, HPLC). The results are compared and discussed. Received: 17 January 1996/Revised: 15 May 1996/Accepted: 17 May 1996     

乳酸-3-苯甲基-2,5-吗啉二酮共聚物的合成及共聚物组分分析

以苯丙氨酸为原料合成3-苯甲基-2,5-吗啉二酮(PMD),以辛酸亚锡为催化剂,研究PMD与丙交酯(LA)开环共聚得到乳酸-3-苯甲基-2,5-吗啉二酮共聚物,用IR、1H-NMR、DSC对共聚物进行分析表征,表明可得到含有苯丙氨酸的聚乳酸共聚物.利用红外定量分析法替代1H-NMR法测定共聚物中PMD的组分含量,以1671.53cm-1和870.82cm-1两波数处特征峰的吸光度比值,作标准工作曲线Y=0.05567X+0.1091,r=0.9993.比较了催化剂浓度、反应时间、温度对共聚物组分含量、共聚物特性黏数[η]的影响.结果表明,低催化剂浓度条件下(0.025mol%与0.1mol%),产物特性黏数[η]随反应时间的延长先增加然后下降;而在高催化剂浓度(0.2mol%)的条件下,因主链中形成了更多更稳定的酰胺键,产物特性黏数[η]10h内维持不变;随PMD加入量的增多,进入共聚物中的PMD组分也相应地呈线性增加,但因PMD的开环活性低于丙交酯,所以苯丙氨酸引入聚乳酸链段中比较困难,但在低投料比条件下(<20mol%),升高反应温度有利于PMD含量的增加;同样也因为PMD在共聚物中组分含量的增多,苯环的稳定性使共聚物[η]受催化剂浓度及温度的影响逐渐减弱.     

Liquid chromatography-nuclear magnetic resonance spectroscopy.

A general overview of the experimental set-up for performing analytical-scale and nanoliter-scale liquid chromatography-1H nuclear magnetic resonance spectroscopy (LC-1H-NMR) experiments is given. The high power of combining LC with 1H-NMR spectroscopy is demonstrated by two examples, where NMR acquisition was performed either in the continuous-flow mode on the analytical scale or in the stopped-flow mode on the nanoliter scale. Current developments employing the on-line coupling of capillary as well as supercritical fluid separation methods with 1H-NMR spectroscopy together with LC-13C-NMR spectroscopy are discussed.     

A3型Corrole中位取代基对其β位1H-NMR的影响

采用密度泛函(DFT)方法对八个中位有不同取代基的A3型corrole进行了几何结构优化和核磁共振(NMR)理论计算. 几何优化结果显示5,10,15-三苯基corrole的两个环内NH异构体的中位苯环空间排布方向不同. 此外, 虽然A3型corrole两个环内NH异构体A和B的能量相差不大, 但A和B分子的Boltzman分布概率却有较大的不同, 且受取代基影响很大. 因而在计算NMR时必须对A和B异构体的理论化学位移做Boltzman统计平均处理. NMR计算结果表明, 在B3LYP/6-311+G(2d,p)//B3LYP/6-31G(d,p)水平下可以得到较为合理的corrole的1H-NMR化学位移结果. β-位氢的化学位移与取代基Hammett常数σ+P的大小成正比关系. 此外, 由于corrole大环的低对称性, 取代基对不同位置β-位氢的NMR影响程度不同, 其β-位氢化学位移的大小和顺序与中位取代基的电子效应和corrole的立体结构因素有关.