9,9-dimethyl-endo-tricyclo<5.2.2.02,6>undecan-4,10-dien-8-one; 9,9-dimethyltricyclo<5.2.2.02,6>undeca-4,10-dien-8-one; (+-)-6,6-dimethyl-(3at,7at)-1,3a,4,6,7,7a-hexahydro-4r,7c-etheno-inden-5-one; (+-)-6
,6-Dimethyl-(3at,7at)-1,3a,4,6,7,7a-hexahydro-4r,7c-aetheno-inden-5-on; Addukt von Cyclopentadien an 1.1-Dimethyl-cyclohexadien-(2,4)-on-(6)