Atomic Electronegativity Interaction Vector and Atomic Hybrid State Index Utilized for Spectroscopic Simulation of 13C Nuclear Magnetic Resonance of Amino Acids

A new method of quantitative structure-spectroscopy relationship (QSSR) is developed for expression of local chemical microenvironment and atomic hybrid state based on both novel atomic electronegativity interaction vector (AEIV) and atomic hybrid state index (AHSI). By AEIV and AHSI, some QSSR models are successfully established for 103 13C NMR chemical shift of 20 natural amino acids. The correlation coefficients of modeling fitting, leave-one-out (LOO) cross-validation-predicted value and leave-molecule-out (LMO) cross-validation-predicted value are 0.9948, 0.9940 and 0.9924, respectively. Then, this model is tested by 13C NMR chemical shift of 4 non-natural amino acids with the prediction correlation coefficients being 0.9940.