Antiproliferative cassaine diterpenoid amines from the leaves and twigs of the traditional Thai medicinal plant Erythrophleum teysmannii (Kurz) Craib.

ETHNOPHARMACOLOGICAL RELEVANCE

Erythrophleum teysmannii (Kurz) Craib is a medicinal plant used by traditional healers in Laos and Thailand to treat cancer. Despite ethnopharmacological reports about plant extracts from this genus as cancer drug formulae, there is a knowledge gap about the chemical composition and potential pharmacological effects of E. teysmannii.

AIM OF THE STUDY

The study aimed to investigate the phytochemical constituents of the leaf and twig DCM/MeOH extract of E. teysmannii and their antiproliferative properties, and to support its traditional uses.

MATERIALS AND METHODS

Bioassay-guided phytochemical investigation of the organic solvent extract of the plant led to the isolation of 21 pure compounds. Their structures were determined by extensive spectroscopic and spectrometric analyses, chemical derivatization and hydrolysis approaches, and ECD computational studies. Pure compounds were assessed for their antiproliferative activities against a panel of NCI-60 human tumor cell lines.

RESULTS

Thirteen new cassaine diterpenoid amine monomers erythroteysamines A-M (1, 4-9, 11-14, 16, and 19) and two new dimers erythroteysamines N and O (20 and 21), together with six previously reported analogues (2, 3, 10, 15, 17, and 18) were isolated. Sixteen compounds were tested in the NCI-60 assay, and they all averaged low micromolar antiproliferative potency.

CONCLUSION

The isolated compounds from E. teysmannii showed antiproliferative activities, providing chemical and pharmacological evidence supporting the traditional use of the plant in herbal medicine.