5,5-二甲基-1,3-环己二酮

4,4-dimethyl-2-oxocyclopentane-1-carbaldehyde

2-Diazo-5,5-dimethyl-3-cyclohexen-1-one

4,4-Dimethyl-1-cyclopentene-1-carboxylic anhydride

(Z)-(4,4-dimethyl-2-oxocyclopentylidene)methyl 4,4-dimethylcyclopent-1-ene-1-carboxylate