5-(hydroxymethyl)-2,3-dimethylcyclopent-2-en-1-one

ethyl 6-ethyl-3-methyl-1,4-dihydropyridazine-5-carboxylate

2,3-二甲基-5-亚甲基-2-环戊烯-1-酮

2-Ethyl-5-methyl-3-furancarbonsaeure-ethylester

(3,4-Dimethyl-2-oxo-cyclopent-3-enyl)-oxo-acetic acid ethyl ester