Chinese Journal of Magnetic Resonance

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ON PRELIMINARY APPROACH TO ESTIMATION AND PREDICTION OF CHEMICAL SHIFT OF 13C NMR SPECTROSCOPY IN FLAVONOIDS ON VECTOR OF
ATOMIC FLECTRONEGATIVE DISTANCE(VAED)

ZHNAG Meng-jun,  LIAO Chun-yang, ZHOU Li-ping, WU Shi-rong,  LI Sheng-shi*   

  1. College of Chemistry and Chemical Engineering (CCCE), Laboratory of Green Chemi stry and Molecular Pharmacy (LGCMP), Chongqing University, Chongqing 400044, China
  • Received:2002-01-14 Revised:2002-04-15 Published:2002-09-05 Online:2002-09-05
  • About author:*Correspondence author
  • Supported by:

    重庆市应用基础项目、国家春晖计划教育部启动基金、霍英东基金及国家新药基金资助项目.

Abstract:

In the present paper, various chemical shifts of 13C NMR for differe nt chemically equivalent carbon atoms in nineteen natural flavonols and twenty one natural flavones were estimated and /or predicted using the atomic electr onegative distance vector(VAED) with 4-element parameter: The sample numbers  N, correlation coefficients R, standard deviation SD, F-statistic value F, regression quadratic sum and residual quadratic sum.are N=285, R=0.796, SD=14.734 , F= 162.315, U=105705.359, Q=60999.156; N=315, R=0.884, SD=12.381, F=369.114, U=1697 45.141, Q=47673.375; N=600, R=0.831, SD=14.122, F=443.449, U=265310.563 and Q=118 859.906, for flavonols, flavones, and flavonoids, respectively. Finally, cross  validation with the leaveone out (LOO) procedure was made by the QSSR equations for all carbon atoms,  with the good results obtained. A relative  reliable correlation model has been developed by the atomic electronegative distance vector , as adjoin structural descriptors. The modelling results were fairly good.

Key words: vector of atomic electronegative distance(VAED), carbon-13 nuclear magnetic resonance spectroscopy, chemical shift, flavonoids

CLC Number: