Selective two-dimensional NMR experiments for topological filtration of fragments of coupling networks
Selective two-dimensional NMR experiments for topological filtration of fragments of coupling networks
复制标题
耦合网络片段拓扑过滤的选择性二维核磁共振实验
DOI：
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发表时间：
1991
期刊：
影响因子：
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通讯作者：
G. Bodenhausen
中科院分区：
文献类型：
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作者：
L. Emsley;G. Bodenhausen
在high-resoln。核磁共振，一个标量耦合自旋的网络可以被分解成编码化学信息的片段。描述了一种新的选择性二维核磁共振相关方法（qsoft-COSYq），它允许人们根据它们的拓扑来识别片段。这些新专家。允许人们对复杂的交叉峰多态进行qzoom，并包括qpassive自旋滤波器（psf），由应用于被动耦合伙伴频率的选择性反转脉冲组成，即不直接对象的自旋。交叉峰多胞胎正在调查中。它演示了如何这样的psf可以插入在二维专家的不同点。而这样的专家又是如何。可以用topol来描述。托波尔。一个片段的耦合和位移可以用矩阵M来表示，而一个选择的专家可以用矩阵P来表示。该技术提供了一种新的自旋体系的识别和分配方法，并在环丙烷衍生物上进行了验证。环状非肽环孢素。[在SciFinder（右）]
In high-resoln. NMR, a network of scalar-coupled spins can be broken down into fragments which encode information about the chem. shifts and couplings that are relevant to a cross-peak multiplet in a two-dimensional correlation (qCOSYq) expt. Novel selective two-dimensional NMR correlation methods (qsoft-COSYq) are described which allow one to identify fragments on the basis of their topol. These new expts. allow one to qzoom inq on complicated cross-peak multiplets and include qpassive spin filtersq (PSFs), consisting of selective inversion pulses applied at the frequencies of passive coupling partners, i.e. spins that are not directly obsd. in the cross-peak multiplets under investigation. It is demonstrated how such PSFs can be inserted at various points in two-dimensional expts. and how such expts. can be characterized in terms of topol. The topol., couplings, and shifts of a fragment may be represented by a matrix M, while a selective expt. can be represented by a matrix P. Several degrees of Mand P can be distinguished. The techniques, which provide a novel method of discriminating and assigning spin systems, are demonstrated on a cyclopropane deriv. and the cyclic undecapeptide cyclosporin. [on SciFinder (R)]