methyl (3aR,4aR,5S,6S,6aR,6bR)-5,6-dichloro-2,2-dimethyltetrahydrocyclobuta[4,5]furo[2,3-d][1,3]dioxole-4a(3aH)-carboxylate

(1R,3R,4R,5R,6S,7S)-methyl 4-acetoxy-6,7-dichloro-3-(2,6-diamino-9H-purin-9-yl)-2-oxabicyclo[3.2.0]heptane-1-carboxylate

(3aR,6aR)-butyl 2,2-dimethyl-3a,6a-dihydrofuro[2,3-d][1,3]dioxole-5-carboxylate

butyl (3aR,4aR,5S,6S,6aR,6bR)-5,6-dichloro-2,2-dimethyltetrahydrocyclobuta[4,5]furo[2,3-d][1,3]dioxole-4a(3aH)-carboxylate