(2R)-11syn-hydroxy-3t-trityloxymethyl-2,3-dihydro-1H-2r,5c-methano-pyrimido[1,2-c][1,3,5]oxadiazepin-9-one

2,3'-((methylamino)imino)-1-(5'-O-benzoyl-3'-deoxy-β-D-lyxofuranosyl)uracil

(3aS)-2t-chloromethyl-3c-(toluene-4-sulfonyloxy)-(3ar,9ac)-2,3,3a,9a-tetrahydro-furo[2',3':4,5]oxazolo[3,2-a]pyrimidin-6-one

2,2'-O-anhydro-3'-O-mesyl-5'-trityluridine