New neo-clerodane diterpenoids from Scutellaria strigillosa with cytotoxic activities

Abstract

Two new neo-clerodane diterpenoids, named scutestrigillosins D and E (1 and 2), were isolated from the whole plant Scutellaria strigillosa. Their structures were established on the basis of detailed physical data analyses. In vitro, two new compounds exhibited cytotoxic activities against four tumor cell lines (HONE-1, P-388, MCF7, and HT29), and gave IC₅₀ values in the range of 3.4–8.9 μΜ.

Keywords:

• Scutellaria strigillosa
• Labiatae
• neo-clerodane diterpenoid
• scutestrigillosins D–E
• cytotoxic activity

Acknowledgements

The authors are grateful to Mr. Zhen-Duo Shen and Ms. Xiu-Li Yin (School of Pharmaceutical Science, Yantai University) for the measurements of FABMS, HR-FABMS, UV, IR and NMR spectra, respectively. The authors also gratefully acknowledge Mr. Hong-Bo Wang (School of Pharmaceutical Science, Yantai University) for the bioactivity screenings.

Disclosure statement

No potential conflict of interest was reported by the authors.