Two new ent-3,4-seco-labdane diterpenoids from Callicarpa nudiflora

Abstract

Two new ent-3,4-seco-labdane diterpenoids, methylcallicarpate (1) and callicarpic acid (2), were isolated from the leaves of Callicarpa nudiflora Hook et Arn. Their structures and relative configurations were established by analysis of spectroscopic data. Their absolute configurations were assigned by the application of the CD technique for the first time among the ent-3,4-seco-labdane-type diterpenes.

Keywords:

• Callicarpa nudiflora
• ent-3,4-seco-labdane diterpenoid
• methylcallicarpate
• callicarpic acid
• CD

Acknowledgements

This work was financially supported by the following grants: Natural Science Foundation of Hainan Province, China (Grant No. 310048); National Natural Science Foundation of China (Grant No. 81060367); National Key Technology R&D Program during the 12th Five-Year Plan Period (Grant No. 2011BAI01B07); 2010 Key Scientific Technology Plan Project of Hainan Province, China (Grant No. ZDXM20100040).