dimethyl 2-((6R,7R,7aS)-3-oxo-6-(prop-1-en-2-yl)tetrahydro-1H,3H-pyrrolo[1,2-c]oxazol-7-yl)malonate

(7S,7aS)-7-[2-(4,4-Dimethyl-2-oxo-oxazolidin-3-yl)-2-oxo-ethyl]-6-[2-hydroxy-1-methyl-eth-(Z)-ylidene]-tetrahydro-pyrrolo[1,2-c]oxazol-3-one

Carbonic acid 2-[(7S,7aS)-7-[2-(4,4-dimethyl-2-oxo-oxazolidin-3-yl)-2-oxo-ethyl]-3-oxo-dihydro-pyrrolo[1,2-c]oxazol-(6Z)-ylidene]-propyl ester methyl ester

[(6S,7S,7aS)-6-(1-Hydroxy-ethyl)-3-oxo-tetrahydro-pyrrolo[1,2-c]oxazol-7-yl]-acetic acid methyl ester

((6S,7S,7aS)-3-Oxo-6-phenylsulfanylmethyl-tetrahydro-pyrrolo[1,2-c]oxazol-7-yl)-acetic acid methyl ester