The reaction of 3-cyano-2H-cyclohepta[b]furan-2-one with enamines derived from isobutyraldehyde gave 2-amino derivatives of 3-cyano-1,1-dimethyl-1,2-dihydroazulene, which on heating with sulfuric acid underwent the elimination of amines accompanied by the migration of the methyl group to give 1,2-dimethylazulenes.

Aramaki-aza-Aoba, Sendai 9802,6-Diamino-1,3,5,7-tetrazacyclopent[f]azulene, a parent compound of zoanthoxanthins, was synthesized from 5,7-dibromo-2-methoxytropone by two step condensation with guanidine.