(S)-((3aR,5R,6R,6aR)-6-Benzyloxy-2,2-dimethyl-6-vinyl-tetrahydro-furo[2,3-d][1,3]dioxol-5-yl)-methoxy-acetaldehyde

3'-C-acetyloxyethyl-3',5'-di-O-benzyl-5-methyl-4'-C-(p-toluenesulfonyloxymethyl)uridine