methyl 2,3-dideoxy-3-fluoro-5-O-(4-phenylbenzoyl)-erythro-pentofuranoside

2-amino-6-chloro-9-(2-O-tosyl-β-D-ribofuranosyl)purine

2-amino-6-chloro-9-(2-deoxy-β-D-threo-pentofuranosyl)purine

6-chloro-9-(5-O-trityl-2-deoxy-β-D-threo-pentofuranosyl)-2-tritylaminopurine

6-chloro-9-(5-O-trityl-2,3-dideoxy-3-fluoro-β-D-erythro-pentofuranosyl)-2-tritylaminopurine