Two new pyranoxanthones from the stem bark of Calophyllum pseudomolle P.F. Stevens

Abstract

Two new pyranoxanthones, calotetrapterins D (1) and E (2), were isolated from the stem bark of Calophyllum pseudomolle P.F. Stevens along with α-mangostin (3). The structures of compounds 1–2 were determined based on 1D NMR (¹H, ¹³C) and 2D NMR (HMQC, HMBC), as well as HRESIMS spectroscopic analysis. Compounds 1–2 showed moderate activity against HeLa and murine leukaemia P-388 cells.

Graphical Abstract

Keywords:

• Calotetrapterins D and E
• pyranoxanthones
• Calophyllum pseudomolle
• cytotoxicity

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

The research is supported by the Research Grant of Penelitian Hibah Mandat, Universitas Airlangga, Indonesia.