(3-N-tert-butyloxycarbonyl-2',3'-O-isopropylidene)uridine 6 、
benzyl 3-(2-acetamido-4,6-O-(R)-benzylidene-3-O-tert-butyldimethylsilyl-2-deoxy-α-D-glucopyranosyl)-2-oxopropylphosphonate 以30%的产率得到benzyl (3-N-tert-butyloxycarbonyl-2',3'-O-isopropylidene)uridin-5'-yl 3-(2-acetamido-4,6-O-(R)-benzylidene-3-O-tert-butyldimethylsilyl-2-deoxy-α-D-glucopyranosyl)-2-oxopropylphosphonate