Two azafluoranthene alkaloids and a phytoecdysone from the stems of Cyclea barbata

Abstract

Two new azafluoranthene alkaloids (1 and 2), and a new phytoecdysone (3), were isolated from the stems of Cyclea barbata Miers, together with six known compounds (4–9). Their structures were elucidated by spectroscopic data analysis and comparison with published data. This is the first report of azafluoranthene alkaloids (1 and 2) and phytoecdysones (3, 8, and 9) from Cyclea genus. In in vitro bioassay, four isolates (3, 5, 6, and 9) showed moderate hepatoprotective activity against N-acetyl-p-aminophenol (APAP)-induced toxicity in HepG2 cells.

Keywords:

• Menispermaceae
• Cyclea barbata
• azafluoranthene alkaloid
• phytoecdysone
• hepatoprotective activity

Acknowledgements

We gratefully appreciate Prof. Sun Hua of Institute of Materia Medica for hepatoprotective bioassay, and we are also grateful to the Department of Instrumental Analysis at our institute for the measurements of IR, NMR, and MS spectra.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by grants from the Natural Science Foundations of China (Nos. 21702233 and 21732008), Young Elite Scientists Sponsorship Program by CAST (YESS, No. 2016QNRC001) and CAMS Innovation Fund for Medical Sciences (CIFMS, No. 2016-I2M-3-015).