[(3aR,4S,6R,6aR)-6-(tert-Butyl-diphenyl-silanyloxymethyl)-2,2-dimethyl-4-phenyl-tetrahydro-furo[3,4-d][1,3]dioxol-4-yl]-acetaldehyde

(1'S,3'R,4'R,5'R,7'S)-N2-isobutyryl-7-(4'-hydroxy-3'-hydroxymethyl-1'-phenyl-2',6'-dioxabicyclo[3.3.0]oct-7'-yl)guanine

(1'S,3'R,4'R,5'R,7'S)-N2-isobutyryl-9-(4'-hydroxy-3'-hydroxymethyl-1'-phenyl-2',6'-dioxabicyclo[3.3.0]oct-7'-yl)guanine

(1'S,3'R,4'R,5'R,7'R)-N2-isobutyryl-7-{4'-acetoxy-1'-phenyl-3'-(tert-butyldiphenylsilyloxymethyl)-2',6'-dioxabicyclo[3.3.0]oct-7'-yl}guanine