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