新型香豆素-7，8-环磷酰胺衍生物的合成与NMR研究

以7-羟基香豆素为原料,经过Mannich反应化学选择性地得到了8位的7-羟基香豆素Mannich碱,然后在三乙胺存在的条件下,与磷酰二氯氮芥发生环合反应得到了一种新型的香豆素-7,8-环磷酰胺衍生物. 通过中间产物Mannich碱和目标产物的NMR图谱,都证实了Mannich反应的化学选择性位点是7-羟基香豆素的8位而不是6位;通过DEPT、¹H-¹H COSY,HSQC和HMBC等2D NMR技术对目标化合物的¹H 和¹³C NMR数据进行了全归属和较详细的解析.      

Zn,Cd和Hg—1.4-BDTA金属配合物分子内重排过程的动态NMR研究

本文测定了1.4—BDTA(1.4—J二胺四乙酸)与逆磁性金属zn,Cd和Hg等的配合物随温度变化的~1HNMR谱及其分子内重排过程.实验结果表明,转化在MMR时间标度内为快过程,而N原子反转为慢过程.用全线型分析方法得到了有关热力学参数,并简单地讨论了Hg—1,4BDTA配合物在较低温度时呈现不对称AB谱的原因.     

Platelet Aggregation Inhibitor from Ganoderma lucidum

Lucidenic acid A ( 1 ) and a new lactone, lucidenolactone ( 2 ) were isolated from the fruiting bodies of Ganoderma lucidum. Their structures were elucidated by spectroscopic method and single-crystal X-ray analysis. Lucidenolactone ( 2 ) showed significant antiplatelet aggregation activity. The NMR spectral data of lucidenic acid A were also reassigned.     

3种单酯型乌头碱的NMR研究

利用3种双酯型乌头碱(乌头碱、新乌头碱、次乌头碱)经水解得到3种单酯型乌头碱,即苯甲酰乌头碱(化合物1)、苯甲酰新乌头碱(化合物2)、苯甲酰次乌头碱(化合物3).应用1D和2DNMR(包括1H-1H COSY、HMQC和HMBC)对这3种化合物的结构进行了分析,纠正了文献对化合物1和化合物2的归属错误,对化合物3的1H和13C化学位移进行了全归属.     

Conformational analysis of cis‐3, 5‐dioxa‐bicyclo[5.4.0]undecane and its 4‐substituted derivatives by DNMR,molecular modeling,and GIAO/DFT methods

Temperature‐dependent ¹H and ¹³C‐NMR spectra of the title compounds are presented. Coalescence effects are discussed and assigned to dynamic process—the interconversion of bicyclic system. The free energies of activation covered the range 39–52 kJ/mol. The dioxepane ring adopts twist‐chair (TC) conformation. GIAO/DFT calculation of isotropic shieldings for the set of low‐energy conformations showed that only one conformer is present at 298 K in solution that matched well with experimental data. Copyright © 2010 John Wiley & Sons, Ltd.     

Internal rotation in enaminonitriles: Investigation by dynamic NMR spectroscopy and molecular modeling

Rotational isomerism in enaminonitriles was studied using dynamic NMR spectroscopy and molecular modeling. It was found that the barrier to rotation about C_vinyl-NH bond was higher for enaminonitriles derived from aliphatic amines than that of enaminonitriles derived from aromatic amines. It was also found that the rotational isomerism about the C_ar-C_vinyl bond also exists in enaminonitriles.     

α-山竹黄酮的NMR研究

应用一维¹H NMR、¹³C NMR、DEPT、二维HMBC、HSQC、¹H-¹H COSY、ROESY对1, 3, 6-三羟基-7-甲氧基-2, 8双(3-甲基-2-丁烯)-9-口山酮（α-mangostin、α-MAG）的¹H、¹³C原子进行了指认归属.     

含手性轴的季戊四醇双缩醛的NMR研究

采用1D和2D梯度场NMR技术(包括1D ¹H NMR, ¹³C NMR, DEPT, 2D ¹H-¹H COSY, HSQC, HMBC),对3,3′-二（2,4-二氯苯基）-2,4,2′,4′-四氧杂螺[5.5]十一烷的4个亚甲基呈现的4组裂分峰进行了明确的归属,也对化合物中其它¹H和¹³C NMR谱信号进行了全归属,为四氧杂螺双缩醛类化合物的结构鉴定提供了充分依据.     

多肽IS4溶液构象的进一步NMR研究

利用二维核磁共振技术对多肽IS4中除Ser-1外的所有残基质子进行了指认.积分NOESY谱中的相关峰可得到距离约束.二面角的约束来自偶合常数³J_NHα.由慢交换质子可得到氢键的约束.在进行距离几何程序计算时利用这些约束可得到一组构象,用能量最优化程序优化后的结果表明,多肽IS4在CF₃CD₂OH中的构象为α-螺旋.     

抗变态反应平喘新药氮斯汀~1H和~(13)C NMR谱线的归属

用１Ｄ（ＮＯＥ差谱、ＤＥＰＴ谱）和２ＤＮＭＲ技术（ＨＨＣＯＳＹ、ＨＭＱＣ和ＨＭＢＣ）归属了合成抗变态反应平喘新药氮卓艹斯汀两种异构体的１Ｈ和１３ＣＮＭＲ谱线