(7aR,8aR,11aR,11bR,11cS)-10,10-dimethyl-1,2,5,7a,8a,11a,11b,11c-octahydro-3H-[1,3]dioxolo[4',5':4,5]furo[3,2-c]pyrrolo[1,2-a]azepin-3-one

(S)-1-Allyl-5-((3aR,5R,6R,6aR)-2,2-dimethyl-5-vinyl-tetrahydro-furo[2,3-d][1,3]dioxol-6-yl)-pyrrolidin-2-one

(S)-4-Azido-4-[(3aR,5S,6R,6aR)-5-((R)-2,2-dimethyl-[1,3]dioxolan-4-yl)-2,2-dimethyl-tetrahydro-furo[2,3-d][1,3]dioxol-6-yl]-butyraldehyde

(S)-4-Azido-4-[(3aR,5S,6R,6aR)-5-((R)-2,2-dimethyl-[1,3]dioxolan-4-yl)-2,2-dimethyl-tetrahydro-furo[2,3-d][1,3]dioxol-6-yl]-butyric acid methyl ester

(S)-1-Allyl-5-[(3aR,5S,6R,6aR)-5-((R)-2,2-dimethyl-[1,3]dioxolan-4-yl)-2,2-dimethyl-tetrahydro-furo[2,3-d][1,3]dioxol-6-yl]-pyrrolidin-2-one