Octacyclic and decacyclic ent-abietane dimers with cytotoxic activity from Euphorbia fischeriana steud

A novel Diels-Alder adduct possesses a 6/6/6/5/6/6/6/6 octacyclic skeleton featured with bicyclo[2.2.2]octane moiety, biseupyiheoid A (1), along with another decacyclic 6/6/6/3/5/6/5/6/6/6 fused diterpenoid dimer, bisfischoid C (2), were isolated from Euphorbia fischeriana. Their structures were determined by spectroscopic, X-ray crystallographic approaches, and quantum mechanical calculations. The structural features of 1 and 2 were hypothesized to involve intramolecular Diels-Alder reactions with different coupling patterns. Dimer 1 showed antiproliferative activity through apoptosis activation in LoVo cells. (C) 2022 Published by Elsevier B.V. on behalf of Chinese Chemical Society and Institute of Materia Medica, Chinese Academy of Medical Sciences.

Automated summary

A novel compound with a unique structure was isolated from Euphorbia fischeriana, and its structure was determined using various techniques. It was found to exhibit antiproliferative activity.