(-)-(R)-5-ethyl-2(5H)-furanone

(Z)-(R)-4-(Tetrahydro-pyran-2-yloxy)-hex-2-enoic acid methyl ester

((2R,3R)-2-Ethyl-5-oxo-tetrahydro-furan-3-yl)-ethylsulfanylcarbonyl-acetic acid methyl ester

2-((2R,3R)-2-Ethyl-5-oxo-tetrahydro-furan-3-yl)-3-oxo-propionic acid methyl ester

(3R,4R)-4-Hydroxy-3-{[2-(1H-indol-3-yl)-ethylcarbamoyl]-methyl}-2-[1-methoxy-meth-(E)-ylidene]-hexanoic acid methyl ester