Acta Phys. -Chim. Sin. ›› 2009, Vol. 25 ›› Issue (09): 1749-1755.doi: 10.3866/PKU.WHXB20090824

• ARTICLE • Previous Articles     Next Articles

Cytotoxic Activity of a Natural ProductWangzaozin A

YANG Xiang-Yan, ZHANG Yi-Heng, DING Lan, WANG Han-Qing   

  1. College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, Shandong Province, P. R. China|International College, Qingdao University of Science and Technology, Qingdao 266061, Shandong Province, P. R. China|College of Life Science, Northwest Normal University, Lanzhou 730070, P. R. China|Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000, P. R. China
  • Received:2009-01-24 Revised:2009-05-30 Published:2009-09-03
  • Contact: ZHANG Yi-Heng E-mail:yhzhang@ustc.edu.cn

Abstract:

Wangzaozin A (1) is an ent-kaurane diterpenoid isolated from Isodon racemosa (Hemsl) Hara. This natural product exhibits significant cytotoxicity against human Bel-7402 and HO-8910 tumor cells. The structural parameters of compound 1 from X-ray diffraction were compared with those from theoretical calculations at B3LYP/6-31G(d) level compound and the theoretical results were found to be in accordance with the experimental data. The 1H and 13C NMR chemical shifts of compound 1 were also calculated using the gauge independent atomic orbital (GIAO) method at the B3LYP level with the 6-31G(d), 6-31G(d,p), 6-31+G(d,p), and 6-31++G(d,p) basis sets. Results showed that the calculated NMR data for the geometrical conformation optimized using the B3LYP/6-31G(d) basis set are the most accurate by comparison to experimental data. The geometrical conformation optimized using the B3LYP/6-31G(d) basis set, therefore, approximates the real geometric structure of compound 1 most accurately. Statistical error analysis for the theoretically predicted δH and δC values versus experimentally observed values for compound 1 was conducted. A molecular electrostatic potential (MEP) map was used in an attempt to identify key features of the diterpenoid Wangzaozin A to account for its anti-tumor activity. MEP investigations reveal that compound 1, which shows anti-tumor activity, possesses electron-rich regions that extend over the hydroxyl and carbonyl groups of compound 1.

Key words: Density functional theory, Protonation, Wangzaozin A, Nuclear magnetic resonance, Molecular electrostatic potential

MSC2000: 

  • O641