Thiosugars. Part 9: Synthesis and Biological Evaluation of Some 4′-Thio- -arabino Nucleoside Analogues

1-O-Acetyl-2,3,5-tri-O-benzyl-4-thio- -arabinofuranose (10) was transformed into the corresponding cytidine derivative 9 and the adenosine derivative 12. Both nucleosides, as well as the previously reported uridine and thymidine analogues 2 and 3, were tested for their in vitro antiviral activity.