1. State Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources
2. School of Chemistry and Pharmaceutical Sciences
3. Guangxi Normal University
4. Guilin 541004
5. P. R. China
6. College of Chemistry and Pharmaceutical Engineering
7. Nanyang Normal University
8. Nanyang 473061
9. MOE Key Laboratory of Synthetic and Natural Functional Molecule Chemistry
10. College of Chemistry and Materials Science
11. Northwest University
12. Xian