3-(2-Allyloxycarbonyl-ethyl)-5-(allyloxycarbonyl-hydroxy-methyl)-4-methyl-1H-pyrrole-2-carboxylic acid tert-butyl ester

3-(2-Allyloxycarbonyl-ethyl)-5-[allyloxycarbonyl-(triphenyl-λ5-phosphanylidene)-methyl]-4-methyl-1H-pyrrole-2-carboxylic acid tert-butyl ester

3-(2-Allyloxycarbonyl-ethyl)-5-{allyloxycarbonyl-[3-eth-(E)-ylidene-4-methyl-5-oxo-pyrrolidin-(2E)-ylidene]-methyl}-4-methyl-1H-pyrrole-2-carboxylic acid tert-butyl ester