Abstract

Aromaticine (systematic name: 4a,8-dimethyl-3-methyl-ene-3,3a,4,4a,7a,8,9, 9a-octa-hydro-azuleno[6,5-b]furan-2,5-dione), C15H18O3, is a natural lactone isolated from Amblyopappus pusillus. The mol-ecular structure and conformation agree with the results of Romo, Joseph-Nathan & Díaz [(1964). Tetra-hedron, 20, 79-85]. The fused-ring system contains a seven-membered ring in a twist-boat conformation and two five-membered rings trans fused in envelope conformations.