PREDICTION OF ANTI AND GAUCHE VICINAL PROTON-PROTON COUPLING-CONSTANTS IN CARBOHYDRATES - A SIMPLE ADDITIVITY RULE FOR PYRANOSE RINGS
PREDICTION OF ANTI AND GAUCHE VICINAL PROTON-PROTON COUPLING-CONSTANTS IN CARBOHYDRATES - A SIMPLE ADDITIVITY RULE FOR PYRANOSE RINGS
复制标题
DOI：
10.1002/mrc.1270130606
复制
发表时间：
1980-01-01
期刊：
影响因子：
--
通讯作者：
HAASNOOT, CAG
中科院分区：
文献类型：
--
作者：
ALTONA, C;HAASNOOT, CAG
取代基的相对取向和电负性对3J(Aa)、3J(Ae)和3J(Ee)的大小的影响可以用一组简单的加法常数来很好地预测，这对碳水化合物中的吡喃糖环是有效的。所提出的一组参数被用来计算各种吡喃糖苷和相关化合物中的327个偶合常数[3J(HH)]。与文献中的实验值的比较表明，构象纯和未形成的分子中的耦合可以以令人惊讶的准确性被预测。对于选定的305个耦合值的组，总体均方根一致性为0.29赫兹。ΔJ(Aa)和ΔJ(Ae)[ΔJ=J(Exp)-J(Calc)]沿吡喃糖体系中每个碳-碳键的统计分解揭示了出乎意料的几何均匀度。
The effect of the relative orientation and electronegativity of substituents on the magnitude of3J(aa),3J(ae) and3J(ee) is well predicated by a simple set of additivity constants, valid for pyranose rings in carbohydrates. The proposed set of parameters is used to calculate 327 coupling constants [3J(HH)] in a variety of pyranosides and related compounds. A comparison with experimental values taken from the literature shows that couplings in molecules which are conformationally pure and underformed can be predicted with a surprising accuracy. An overall root‐mean‐square agreement of 0.29 Hz is attained for a selected group of 305 coupling values. A statistical breakdown of ΔJ(aa) and ΔJ(ae) [ΔJ=J(exp)‐J(calc)] along each carbon‐carbon bond in the pyranose systems reveals an unexpected degree of geometrical homogeneity.