六氟磷酸二(2,2'-联吡啶)·(4,4'-二甲基-2,2'-联吡啶) 合钌(Ⅱ)的二维核磁共振谱分析

用一维NMR方法研究了电化学发光物质六氟磷酸二(2,2'-联吡啶)·(4,4'-二甲基-2,2'-联吡啶)合钌(Ⅱ)的立体结构,借助二维1H-1H COSY和1H-13C COSY实验技术对其氢谱和碳谱进行了完全的归属,并给出了其氢谱和碳谱的化学位移值.     

六氟磷酸二(2,2’-联吡啶)(2,2’-联吡啶-4,4’-二羧酸)合钌(Ⅱ)的二维核磁共振谱分析

利用核磁共振氢谱和碳谱研究了电化学探针六氟磷酸二(2,2＇-联吡啶)(2,2＇-联吡啶-4,4’-二羧酸)合钌(Ⅱ)的立体结构,并通过二维~1H~1同核相关及~1H-~(13)C异核相关技术对其氢谱和碳谱进行了归属.     

六氟磷酸二(2,2′-联吡啶)(2,2′-联吡啶-4,4′-二羧酸)合钌(Ⅱ)的二维核磁共振谱分析

利用核磁共振氢谱和碳谱研究了电化学探针六氟磷酸二(2,2′-联吡啶)(2,2′-联吡啶-4,4'-二羧酸)合钌(Ⅱ)的立体结构,并通过二维1H-1H同核相关及1H-13C异核相关技术对其氢谱和碳谱进行了归属.     

六氟磷酸二（2,2—联吡啶）（2,2‘—联吡啶—4,4’—二羧酸）合钌（Ⅱ）的二？…

利用核磁共振氢谱和碳谱研究了电化学探讨六氟磷酸二（２,２’－联吡啶）（２,２‘－联吡啶－４,４＝－二羧酸）合钌（Ⅱ）的立体结构,并通过二维’Ｈ－Ｈ同核相关及Ｈ－＾１３Ｃ异相关技术对其氢谱和碳谱进行了归属。     

钯碳催化法合成4,4'-二甲基-2,2'-联吡啶

以4-甲基吡啶为原料, 钯碳催化合成了4,4'-二甲基-2,2'-联吡啶. 通过¹H NMR, GC-MS, 元素分析对产物进行了表征, 对催化反应进行了分析, 并且讨论了钯碳催化反应的机理.     

联吡啶和邻菲咯啉混配的钌配合物的核磁共振氢谱分析

合成了Ru(bpy)2(phen)(PF6)2 和Ru(bpy)(phen)2(PF6)2 (bpy和phen分别为2,2′-联吡啶和1,10 -邻菲咯啉)两种电化学发光物质,以 1HNMR谱研究这两种配合物的立体结构,利用 1H - 1HCOSY(同核相关谱)核磁共振技术详细分析并归属了它们的氢谱峰。     

4,4'-二(对氨基苯乙炔基)-6,6'-二[N,N-二(乙氧基羰甲基)氨甲基]-2,2'-联吡啶的合成与表征

以4,4'-二硝基-2,2'-联吡啶-6,6'-二亚甲基双三氟乙酸酯作为起始原料, 经水解、 溴化、 酯化和对氨基苯乙炔取代4步反应合成了4,4'-二(对氨基苯乙炔基)-6,6'-二[N,N-二(乙氧基羰甲基)氨甲基]-2,2'-联吡啶. 通过红外光谱、 核磁共振波谱、 高分辨质谱等表征了该化合物的结构. 该化合物经水解后与铕离子形成稀土荧光螯合物, 在紫外光激发下, 发射出具有铕离子特征的荧光光谱.     

叠氮二(2,2''-联吡啶)钌(Ⅱ)配合物的光物理和光化学性质

本文研究了叠氮二(2,2'—联吡啶)钌(Ⅱ)配合物在有机溶剂及乙腈—水中的一些光物理和光化学性质。在77K的甲醇—乙醇玻璃态时,用245nm等波长激发表现较强的荧光,其最大发射峰在540nm,另一弱带在580nm。在室温甲醇中测得的磷光发射是弱的,且寿命<15us。 在254nm、300nm及514nm照射下,光反应机制及量子产率与溶剂、照射波长有关。在乙腈—水及乙腈中,分别用254nm和514nm照射均发生取代反应,最后的光产物为Ru(bpy)₂(N₃)(CH₃CN)⁺,配合物消失的量子产率分别为0.129±0.008mol einstein^-1及(6.77±0.22)×10^-5mol einstein^-1;在乙腈—水中用514nm照射,生成的光产物先是Ru(bpy)₂(N₃)(CH₃CN)⁺,再生成Ru(bpy)₂(CH₃CN)₂²⁺,配合物消失的量子产率为(5.32±0.13)×10^-4mol einstein^-1。     

叠氮二(2,2′-联吡啶)钌(Ⅱ)配合物的光物理和光化学性质

本文研究了叠氮二(2,2′—联吡啶)钌(Ⅱ)配合物在有机溶剂及乙腈—水中的一些光物理和光化学性质。在77K的甲醇—乙醇玻璃态时,用245nm等波长激发表现较强的荧光,其最大发射峰在540nm,另一弱带在580nm。在室温甲醇中测得的磷光发射是弱的,且寿命<15us。 在254nm、300nm及514nm照射下,光反应机制及量子产率与溶剂、照射波长有关。在乙腈—水及乙腈中,分别用254nm和514nm照射均发生取代反应,最后的光产物为Ru(bpy)_2(N_3)(CH_3CN)~ ,配合物消失的量子产率分别为0.129±0.008mol einstein~(-1)及(6.77±0.22)×10~(-5)mol einstein~(-1);在乙腈—水中用514nm照射,生成的光产物先是Ru(bpy)_2(N_3)(CH_3CN)~ ,再生成Ru(bpy)_2(CH_3CN)_2~(2 ),配合物消失的量子产率为(5.32±0.13)×10~(-4)mol einstein~(-1)。     

2,2'-联吡啶-3,3'-二羧酸锰(Ⅱ)配合物的合成、晶体结构及性能研究

以2,2’-联吡啶-3,3’-二羧酸(H2L)和1,10-邻菲啰啉(Phen)为配体合成了一个新的锰(Ⅱ)配合物[Mn(H2O)(L)(Phen)2]· (H2O)3.该配合物晶体属单斜晶系,空间群P21/c.在配合物中,中心锰(Ⅱ)离子的配位数是6,处于变形的八面体配位环境中.还测定了标题配合物的磁性,荧光和电化学性能,结果表明:在低温下,配合物有反铁磁性;当激发波长为656 nm时,配合物在682 nm附近有一个宽的荧光发射峰;在循环伏安过程中配合物的电子转移是准可逆的,对应的电极反应是Mn(Ⅲ)/Mn(Ⅱ).     

2,2'-二(对胺苯甲酯)-1,1'联萘的核磁共振谱解析

利用~1HNMR,~(13)CNMR谱研究了2,2’-二(对胺苯甲酯)-1,1’联萘的结构,并通过~1H-~1HCOSY,~(13)C-~1H异核相关及~(13)C-~1H异核远程相关谱进一步地确定了~1H谱和~(13)C谱中各谱峰的归属,为同类化合物的表征提供了一个依据.     

4—叠氮—4—脱氧—4‘—去甲基表鬼臼毒素的^1H和^13C核磁共振分析

用＾１Ｈ－＾１ＨＣＯＳＹ，ＨＭＱＣ和ＲＯＥＳＹ二维核磁共振等技术对标题化合物的氢谱和碳谱进行了完全归属。     

Quality Control of Krill Oil by Nuclear Magnetic Resonance (NMR) Spectroscopy: Composition and Detection of Foreign Species

Krill oil is currently among the most highly promoted products in the dietary supplement market, which, due to its high price, can be potentially adulterated with fish species and artificial oil. For a holistic control of krill oil quality, ¹H, ¹³C, and ³¹P nuclear magnetic resonance (NMR) spectroscopies were used. The fatty acid and phospholipid composition as well as secondary ingredients, such as homarine, amino acids, and chitin, were examined. The following phospholipid species were detected: phosphatidylcholine (75–85?mol %), phosphatidylethanolamine (4–7?mol%) and their lyso derivatives 1-lysophosphatidylcholine (1–2?mol%)–2-lysophosphatidylcholine (10–16?mol%) and lysophosphatidylethanolamine (1?mol%). In the -2 position of phospholipids, the content of eicosapentaenoic acid (mean 68.23%; relative standard deviation 2.23%) was twice as high as the content of docosahexaenoic acid (mean 31.77%; relative standard deviation 4.79%). ¹³C NMR spectroscopy was used to distinguish between krill and fish oil-based dietary supplements. The adulteration of krill oil can be detected by fatty acid distribution in the sn-2 triacylglycerol position. The sensitivity of the method is about 10% (w/w) of fish content in blends, which is enough to detect deliberate adulteration. The same methodology can be used to recognize synthetically modified krill oil. The method was successfully applied to 30 commercially available krill and fish oil supplements.     

精氨酸甘草次酸的制备及核磁共振谱分析

以18β-甘草次酸为原料,合成了一种新的甘草次酸盐类衍生物——精氨酸甘草次酸,利用1HNMR、13CNMR、DEPT、1H-1HCOSY、HMQC、HMBC等1D和2DNMR技术对其碳和氢质子信号进行了全归属,并通过与两种原料化合物核磁共振谱数据的对比,揭示了该成盐反应的作用机制和产物的结构类型。     

Kinetics of Core‐Shell Nanoparticle Formation by Two‐Dimensional Nuclear Magnetic Resonance

We have studied the kinetics of polymeric nanoparticle formation for poly(styrene‐block‐4‐vinylpyridine) [P(S‐b‐4‐VPy)], chains in a non‐selective solvent using 1,4‐dibromobutane (DBB) as a cross‐linker by means of different nuclear magnetic resonance (NMR) spectroscopy techniques. The kinetic process was followed using ¹H, ¹³C, and 2‐D Heteronuclear Single Quantum Correlation (HSQC) NMR experiments. The kinetic data obtained from 2‐D HSQC and ¹H NMR experiments were in good agreement between them, proving the reliability of the 2‐D HSQC NMR technique for the in situ study of the kinetics of core‐shell nanoparticle formation. A value of 1.5 × 10⁻⁵ s⁻¹ was determined for the apparent kinetic constant of the P(S‐b‐4‐VPy)‐DBB core‐shell nanoparticle formation process.

     

Determination of Linoleic Acid Oxylipins in Chinese Baijiu Using Ultra-Performance Liquid Chromatography with Quadruple-Time-of-Flight Mass Spectrometry (UPLC-QTOF-MS) and Nuclear Magnetic Resonance (NMR)

Linoleic acid oxylipins may adversely affect the quality of food products. To investigate the presence of linoleic acid oxylipins in Chinese Baijiu (distilled spirits), nine representative samples were analyzed using ultra-performance liquid chromatography coupled with quadruple-time-of-flight mass spectrometry (UPLC-TOF-MS) in the negative electrospray ionization (ESI) mode. For the first time, 12 oxylipins were identified in Baijiu via UPLC-TOF-MS and nuclear magnetic resonance spectroscopy (NMR). Moreover, a rapid and accurate internal standard (IS) quantification method was developed to determine these oxylipins in Baijiu by UPLC coupled with triple-quadrupole mass spectrometry. The method demonstrated acceptable precision, accuracy, and recovery, and was successfully applied to analyze the nine Baijiu samples. The afforded results indicated that in the soy sauce and strong aroma-type Baijiu samples, linoleic acid oxylipin was present in concentrations ranging from 1.27 to 104.90?μg/L; these values were significantly higher than those observed in the light aroma samples (P?<?0.01). This study proposes a quantitation method to monitor and control the linoleic acid oxylipin contents in Baijiu and provides new insights into the lipid metabolites of this distilled spirit.     

二萜生物碱的~(13)C核磁共振谱

本文通过对186个二萜生物碱及其衍生物的~(13)C NMR谱数据的分析比较,就以下几方面作了归纳总结:①信号归属的方法;②常见取代基OCH_3、NCH_3、、NCH_2CH_3、OCOCH_3、的化学位移范围;③季碳和某些特定碳的化学位移规律。某些特定结构,如C_(20)二萜生物碱中的噁唑烷环以及C_(20)差向异构体等的~(13)C NMR谱特征;④C_(19)二萜生物碱中不同位置上取代基(H→OH、H→OMe、OH→OAc、OH→OMe、OH→C=O)效应和立体化学效应。这些归纳总结有助于此类化合物结构的阐明。     

配合物Ru(dcbpy)(phen)2(PF6)2的2D-NMR分析

用一维ＮＭＲ方法研究了新型电化学发光探针Ｒｕ（ｄｃｂｐｙ）（ｐｈｅｎ）２（ＰＦ６）２的立体结构,借助二维＾１Ｈ－＾１Ｈ ＣＯＳＹ和＾１Ｈ－＾１３Ｃ ＣＯＳＹ实验对其氢谱和碳谱进行了完全的归属,并给出了其氢谱和碳谱的化学位移值。     

4-氨基-5-[2-(4-氯苯氧甲基)苯并咪唑-1-亚甲基]-1,2,4-三唑-3-硫酮的核磁共振研究

在无水乙醇和KOH存在下,将2-(4-氯苯氧甲基-1-苯并咪唑乙酰肼(1)与CS2反应,合成出了中间体酰肼二硫代甲酸钾盐.此中间体再与过量的水合肼反应,经环化得到一种新化合物4-氨基-5-[2-(4-氯苯氧甲基)苯并咪唑-1-亚甲基]-1,2,4-三唑-硫酮.采用元素分析、IR及NMR技术确定了新化合物的结构,并利用2...