Ent-trachylobane-3β-hydroperoxide, a new diterpene from the root bark of Chrozophora oblongifolia (Fam.; Euphorbiaceae)

Abstract

New ent-trachylobane-3β-hydroperoxide (5) together with four known compounds, ricinine (1), trimethoxy ellagic acid (2), dimethoxy ellagic acid (3) and aleurotolic acid (4) were isolated from the methylene chloride fraction of the root bark of Chrozophora oblongifolia. The structures of these secondary metabolites were elucidated by using different spectroscopic techniques, ¹H NMR, ¹³C NMR, HSQC, HMBC, ¹H-¹H COSY, NOESY, HR-ESI-MS, EI-MS and comparison with published data. Ent-trachylobane-3β-hydroperoxide showed moderate cytotoxic activity by MTT assay method against human breast cancer cells (MCF-7) and human hepatocyte-derived carcinoma cells (Huh-7) with IC₅₀ values of 24.53 and 34.13 µM, in comparison with IC₅₀ values of 23.47 µM and 15.82 µM for 5-fluorouracil respectively.

Keywords:

• Trachylobane
• diterpene
• Chrozophora oblongifolia
• cytotoxicity and MTT assay

Acknowledgements

We would like to acknowledge the department of Agro-Environmental Sciences, Faculty of Agriculture, Kyushu University, Fukuoka, Japan, for carrying out the spectroscopic analysis and cytotoxicity study. The authors also would like to thanks to Mr. Hossam El-Feky, a pharmacist in Egyptian ambulance Authority in South Sinai for his great efforts in collecting the plant material, which is the base for this work.

Disclosure statement

The authors declare that they don't have any conflict of interest.