Two isomeric di­deoxy­nucleosides

We have synthesized two isomeric di­deoxy­nucleosides. 4(S)‐(6‐Amino‐9H‐purin‐9‐yl)‐3‐methyl­ene‐2,3,4,5‐tetra­hydrofuran‐2(S)‐yl­methanol, C₁₁H₁₃N₅O₂, is an analogue of the anti‐HIV compound (S,S)‐isodi­deoxy­adenosine (isoDDA) with an exocyclic methyl­ene group and is found to be anti‐HIV inactive. The solid‐state comformation is very similar to that of isoDDA. 4(S)‐(6‐Amino‐3H‐purin‐3‐yl)‐3‐methyl­ene‐2,3,4,5‐tetra­hydro­furan‐2(S)‐ylmethanol, C₁₁H₁₃N₅O₂, has an isomeric arrangement of the carbohydrate and base moieties, as confirmed by the crystal structure analysis. The asymmetric unit contains two independent mol­ecules that differ in conformations at the sugar moiety.