This article deals with a formal total synthesis of (t)~ quadrone (1), an antitumor sesquiterpene. The cyclopentenone (1) was trans—formed into cyclopropane derivative (g), a regioselective reductive ring opening of which and trapping of the enolate intermediate (lg) by a C—1 unit afforded the diquinaneacetate (11). By a two—step sequence ll was converted into methyl (1R*, 5R*, 6R*)—6—(2—hydroxyethyl)—7, 7-dimethyl—2— ...
