2-amino-3-hydroxycyclopent-2-en-1-one,hydrochloride

2-(dimethylaminomethylidene)cyclopentane-1,3-dione

3-[methyl(3-methylbut-2-enyl)amino]cyclopent-2-en-1-one

3-methoxy-N-methylcyclopent-2-en-1-imine

(3-oxo-5-prop-2-enylcyclopenten-1-yl) acetate