acetic acid,1-cyclopenta-2,4-dien-1-ylideneethanol

1-[5-(1-hydroxyethylidene)cyclopenta-1,3-dien-1-yl]ethanone

螺[2.4]庚-4,6-二烯

4-(hydroxymethylidene)cyclopenta-2,5-diene-1,2-dicarbaldehyde

1,5,5-三甲基环戊二烯