Isolation and characterization of cytotoxic compounds from Euphorbia cornigera Boiss.

Abstract

Methanolic extract of Euphorbia cornigera shoots was separated using HPLC, affording compounds 1–4. Their structures and relative stereochemistry were established after obtaining their spectroscopic (IR, ¹H, ¹³C NMR COSY-45°, HOHAHA, HSQC, HMBC, NOESY, and mass measurement) data. On the basis of these data, the compounds were characterized as 3-O-(2,3-dimethylbutanoyl)-13-O-dodecanoyl-20-O-tetradecanoylingenol (1), 3-O-decanoyl-20-O-hexanoylingenol (2), 3-O-(2,3-dimethylbutanoyl)-13-O-dodecanoyl-20-O-hexadecanoylingenol (3), and 13-O-dodecanoyl-20-O-hexanoylingenol (4); among these compounds, two (1 and 2) were new metabolites while the rest (3 and 4) were known. The MTT cytotoxicity assay was carried out using amrubicin hydrochloride as a positive control. Compound 1 displayed IC₅₀ as 5.0 and 2.9 μM against RAW and HT-29 cell lines, respectively, which is 5- and 1.5-folds stronger than the control with IC₅₀ values of 25 and 4.36 μM, respectively.

Keywords:

• Euphorbia cornigera Boiss.
• Euphorbiaceae
• cytotoxicity
• ingenol