Neogenkwanine I from the flower buds of Daphne genkwa with its stereostructure confirmation using quantum calculation profiles and antitumor evaluation

Abstract

Neogenkwanine I (1), a new daphnane-type diterpene with 4,7-ether group, along with four known ones (2–5), were isolated from Daphne genkwa. The structure including absolute configurations of 1 was established on the basis of NMR, ¹³C-NMR and ECD calculations and CD exciton chirality analysis. ¹³C-NMR and ECD calculations of daphnane-type diterpenes were reported here for the first time. All of the diterpenes were screened for their cytotoxic activities against MCF-7 and Hep3B cell lines. The cytotoxicity structure- activity relationship of compounds was illustrated with the absence of ortho-ester group of daphnane-type diterpenes.

Graphical Abstract

Keywords:

• Daphne genkwa
• daphnane-type diterpenes
• 13C-NMR and ECD calculations
• cytotoxicity
• structure-activity relationship

Disclosure statement

No potential conflict of interest was reported by the authors.

Acknowledgments

Financial support from the National Nature Science Foundation of China (81573319, 81673324), the Foundation (L2015518) from the Project of Education Department of Liaoning Province of China, the Liaoning province Natural Science Foundation of China (201602705), the Support Plan for Youth Teacher of Shenyang Pharmaceutical University (ZQN2015031) and Key Laboratory of Computational Chemistry-Based Natural Antitumor Drug Research & Development, Liaoning Province are gratefully acknowledged.