2-methyl-2-(3-oxobutyl)cyclopentane-1,3-dione

2-methyl-3-pyrrolidin-1-ylcyclopent-2-en-1-one

2-methyl-2-phenylsulfanylcyclopentane-1,3-dione

2-methylidenecyclopentane-1,3-dione

3-bromo-2-methylcyclopent-2-en-1-one