Methyl 2-(1a,4a-dimethyl-2,8-dioxo-2,3,4,4a,5,6,7,8-octahydro-1aH-1- oxacyclopropa[d]naphthalen-7-yl)acrylate

Abstract

The title compound, C 16H 20O 5, was synthesized from ilicic acid [2-(8-hydroxy-4a,8-dimethyldecahydronaphthalen-2- yl)acrylic acid], which was isolated from the chloroform extract of the aerial part of Inula viscose (L) Aiton [or Dittrichia viscosa- (L) Greuter]. The molecule is built up from two fused six-membered rings, the epoxidized six-membered ring adopts a half-chair conformation while the other ring displays a perfect chair conformation. The crystal structure features C - H⋯O hydrogen bonds.