methyl 2-[(3R)-3-hydroxy-5-oxocyclopenten-1-yl]acetate

[(R)-5-Oxo-3-(tetrahydro-pyran-2-yloxy)-cyclopent-1-enyl]-acetic acid methyl ester

(3S,1'R)-5-(1'-carboxy-3'-methylbutoxy)imino-3-hydroxy-1-cyclopentene-1-acetic acid methyl ester

6-Benzyloxymethyl-7-hydroxy-8-iodo-2-oxabicyclo[3.3.0]octan-3-one