3-(((6aR,8R,9R,9aR)-8-(2,4-dioxo-3,4-dihydropyrimidin-1(2H)-yl)-2,2,4,4-tetraisopropyltetrahydro-6H-furo[3,2-f][1,3,5,2,4]trioxadisilocin-9-yl)oxy)propanamide

N3-benzoyl-5'-O-(4,4'-dimethoxytrityl)-2'-O-(2-methoxycarbonylethyl)uridine

N3-benzoyl-2′-O-(2-methoxycarbonylethyl)uridine

2'-O-[2-(methoxycarbonyl)ethyl]-3',5'-O-(1,1,3,3-tetraisopropyldisiloxane-1,3-diyl)uridine

5′-O-(4,4′-dimethoxytrityl)-N3-benzoyl-2′-O-(2-methoxycarbonylethyl)uridine 3′-(2-cyanoethyl N,N-diisopropylphosphoramidite)