1-{[(4S,5S)-5-ethynyl-2,2-dimethyl-1,3-dioxolan-4-yl]methyl}-2-(trimethylsilyl)pyrrolidine

(3aS,8aR,9aS)-2,2-dimethyl-9-methylene-octahydro[1,3]dioxolo[4,5-f]indolizine

2,2-dimethyl-hexahydro-1,3-dioxa-4a-aza-s-indacen-8-one

2,2-dimethyl-octahydro-1,3-dioxa-4a-aza-s-indacen-8-ylamine

(3aS,8aR,9R,9aS)-9-Azido-2,2-dimethyl-hexahydro-1,3,6-trioxa-4a-aza-cyclopenta[b]naphthalene