Two new monoterpenoid indole alkaloids from the kernels of Kopsia arborea

Abstract

Two new monoterpenoid indole alkaloids, (2 R, 7 R, 16 R, 20 R, 21S)-12-hydroxypleiocarpine (1) and (2S, 7 R, 16S, 20 R, 21S)-N-methoxycarbonyl-11,12-methylenedioxy-Δ^14,15-kopsinaline (2), along with six known alkaloids were isolated from the methanol extract of the kernels of Kopsia arborea. Their structures including the absolute configurations were elucidated by HRESIMS, NMR spectroscopy, and quantum computational methods. Their cytotoxicity against two human cancer cell lines were also evaluated.

Graphical Abstract

Keywords:

• Apocynaceae
• Kopsia arborea
• kernels
• monoterpene indole alkaloids

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

We are grateful for the National Science Foundation of China (81874295), and Top Young Talent of the Ten Thousand Talents Program of Yunnan (to Y. Zhang) for financial support.