(2R,3R,4S,5R)-2-[6-(6-bicyclo[2.2.1]heptanylamino)purin-9-yl]-5-(hydroxymethyl)oxolane-3,4-diol
(2R,3S,4R,5R)-2-(hydroxymethyl)-5-[6-(norbornan-2-ylamino)purin-9-yl]tetrahydrofuran-3,4-diol
(2R,3S,4R,5R)-2-(hydroxymethyl)-5-[6-(2-norbornanylamino)-9-purinyl]tetrahydrofuran-3,4-diol