Prelog-Djerassi lactone

(+)-Prelog-Djerassi lactonic acid

(2S,3S,5R,αR)-Tetrahydro-α,3,5-trimethyl-6-oxo-2H-pyran-2-acetic acid

(R)-2-[(3R,5S,6S)-3,5-Dimethyltetrahydro-2-oxo-2H-pyran-6-yl]propionic acid

(2R)-2-(3,4,5,6-Tetrahydro-3β,5β-dimethyl-6-oxo-2H-pyran-2α-yl)propionic acid