Antiproliferative Cassane Diterpenoids of Cordyla madagascariensis ssp. madagascariensis from the Madagascar Rainforest

Abstract

Bioassay-guided fractionation of an ethanol extract of a Madagascar collection of the fruits of Cordyla madagascariensis ssp. madagascariensis led to the isolation of the four new cassane diterpenoids 1−4. The ¹H and ¹³C NMR spectra of all compounds were fully assigned using a combination of 2D NMR experiments, including COSY, HSQC, HMBC, and ROESY sequences. All of the isolates were tested against the A2780 human ovarian cancer cell line, and compounds 1 and 2 showed mild antiproliferative activity with IC₅₀ values of 10 and 36 µM, respectively.