Cycloartane Triterpenes and Ingol Diterpenes Isolated from Euphorbia neriifolia in a Screening Program for Death-Receptor Expression-Enhancing Activity

Abstract

In our screening program for natural products that increase death-receptor 5 expression, seven new cycloartane triterpenes, euphonerins A–G (1–7), and 3-O-acetyl-8-O-tigloylingol (8), a new ingol diterpene, were isolated from the MeOH extract of Euphorbia neriifolia leaves, together with 3,12-di-O-acetyl-8-O-tigloylingol (9), (24R)-cycloartane-3β,24,25-triol (10), and three known flavonols (11–13). The structures of 1–8 were elucidated by spectroscopic analysis. Among these compounds, 1–11 showed death-receptor 5 expression enhancing activity.

Key words

Euphorbia neriifolia - Euphorbiaceae - cycloartane triterpene - ingol diterpene - death receptor - TRAIL

• References

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