New diterpenoids from Sapium discolor

Abstract

Chemical fractionation of the ethanolic extract generated from the twigs and leaves of Sapium discolor led to the isolation and identification of four new macrocyclic diterpenoids including three members of the rare casbane family, sapidisins A-C (1–3), and an analog of the cembrane class, sapidisin D (4), a new 3,4-seco ent-kaurane diterpenoid (5), and 18 known phenolic compounds. Their structures were elucidated by comprehensive spectroscopic analyses especially 1D NMR ¹H-¹H couplings and 2D NMR ROESY data. The discovery of 1–4 from S. discolor provides a clue for further study on the biogenetic evolution of the widely existent tigliane-type diterpenoids in the Sapium species.

Keywords:

• Macrocyclic diterpenoid
• casbane
• cembrane
• ent-kaurane
• Sapium discolor

Acknowledgments

Financial support from the National Natural Science Foundation [No. 81322045] and [No. 81321092] of China is gratefully acknowledged. We thank Prof. S.M. Huang of Hainan University for the identification of the plant material.

Disclosure statement

No potential conflict of interest was reported by the authors.