With access to multigram scale quantities of 1 a series of 4'-thioribo and 4'-thioarabino nucleosides were targeted. A pathway to access these was proposed from 4'-thiouridine 14 (Scheme 3). Comparative literature for the synthesis of 2,'3',5'-tri-O-benzoyl protected uridine involved refluxing the reactants for 3 h in acetonitrile, following silyation of the nucleobase. However, reaction under these conditions for 1 produced low yields of 13 (20-30%). By conducting the reaction just below the boiling point of MeCN, at 75 °C, the yield improved significantly, to 74. The β-anomer of 13 formed preferentially ( 1 H NMR of crude 13 indicated a 10/1, β/α ratio, [ 3 JH1-H2 = 6.8 Hz for β-13]) and the reaction was scalable to 10 g. Global deprotection of 13 was completed using 7 M NH3 in MeOH to obtain 4'-thiouridine 14 in 96% yield. This material was next converted to its cytosine form, first by treatment of 14 with POCl3 and then 1,2,4-triazole to furnish the heterocyclic intermediate, before a final treatment with NH3 in MeOH concomitantly substituted the triazole and removed the benzoyl protecting groups to give 4'thiocytidine 15 in 77% yield over two steps.