(3R,3aS,7aS)-N-formal-3-(pivaloyloxy)-3a-[3,4-(methylenedioxy)phenyl]-2,3,3a,6,7,7a-hexahydroindol-6-one

2,2-Dimethyl-propionic acid (3aS,4aS,7R,7aR,7bR)-7a-benzo[1,3]dioxol-5-yl-5-formyl-2,2,3a-trimethyl-octahydro-[1,3]dioxolo[4',5':3,4]cyclopenta[1,2-b]pyrrol-7-yl ester

((4S,5R)-2,2,4-Trimethyl-5-vinyl-[1,3]dioxolan-4-yl)-acetaldehyde

(3S,4R)-3-methyl-3,4-O-isopropylidene-5-hexenal dimethyl acetal

(4S,5S)-5-(2,2-Dimethoxy-ethyl)-2,2,5-trimethyl-[1,3]dioxolane-4-carbaldehyde