2-amino-1,9-dihydro-9-(2-fluoro-3-hydroxy-4-(hydroxymethyl)cyclopentyl)-6H-purin-6-one, (1alpha,2beta,3beta,4alpha)-isomer
2-amino-1,9-dihydro-9-(2-fluoro-3-hydroxy-4-(hydroxymethyl)cyclopentyl)-6h-purin-6-one, (1alpha,2beta,3beta,4alpha)-isomer