Cytotoxic Macrocyclic Diterpenoid Esters from Euphorbia cornigera

Abstract

Root extract of Euphorbia cornigera Boiss. (Euphorbiaceae) was separated into seven (compound 1 - 7) isolates through multiple Craig’s distributions and preparative HPLC. The structures and relative configuration of theses compounds were established via spectral analyses as 7,8,12-O-triacetyl-3-O-(2-methylbutanoyl)-ingol (1), 3,8,12-O-triacetyl-7-O-(2-methylbutanoyl = -ingol (2), 3,7,12-O-triacetyl-8-O-(2-methylbutanoyl)-ingol (3), 3,7,8-O-triacetyl-12-O-(2-methylbutanoyl)-ingol (4), 7,12-O-diacetyl-3-O-(2-methylbutanoyl)-8-O-methylingol (5), 3,12-O-diacetyl-7-O-(2-methylbutanoyl)-8-O-methylingol (6) and 3,7-O-diacetyl-12-O-(2-methylbutanoyl)-8-O-methylingol (7). All these compounds, except for 2, are novel metabolites and have not been reported earlier. It has further been demonstrated that all the compounds (1 - 7) are cytotoxic.

Key words

Euphorbia cornigera - Euphorbiaceae - ingol esters - cytotoxicity

References

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