methyl (1R)-{1-methyl-2-[(trimethylsilyl)oxy]cyclopent-2-en-1-yl}propanoate

methyl (1R,E/Z)-3-(3-ethylidene-1-methyl-2-oxocyclopentyl)propanoate

methyl 3-(1-methyl-2-oxocyclopentyl)propanoate