methyl 2-[(1S)-4-oxocyclopent-2-en-1-yl]acetate

((1S)-4-oxocyclopent-2-enyl)acetic acid

methyl 2-((1S,2R)-2-((S,E)-6-((tert-butyldimethylsilyl)oxy)hept-1-en-1-yl)-4-oxocyclopentyl)acetate

methyl 2-((1S,2R,4R)-2-((S,E)-6-((tert-butyldimethylsilyl)oxy)hept-1-en-1-yl)-4-hydroxycyclopentyl)acetate

methyl 2-((1S,2R,4R)-2-((S,E)-6-((tert-butyldimethylsilyl)oxy)hept-1-en-1-yl)-4-((2-methoxyethoxy)methoxy)cyclopentyl)acetate