1 FAX [(1r,2s,4r)-4-{[6-amino-5-(formylamino)pyrimidin-4-yl]amino}-2-hydroxycyclopentyl]methyl dihydrogen phosphate 1.000 2 FOX ((1r,2s,4r)-4-{[2-amino-5-(formylamino)-6-oxo-3,6-dihydropyrimidin-4-yl]amino}-2-hydroxycyclopentyl)methyl 5'-phosphate 0.880 3 LWM [(1r,2s,4r)-4-{[2-amino-5-(formylamino)-6-oxo-1,6-dihydropyrimidin-4-yl]amino}-2-hydroxycyclopentyl]methyl dihydrogen phosphate 0.880 4 8NI N-[(5s)-2-amino-5-formamido-6-oxo-5,6-dihydropyrimidin-4-yl]-2-deoxy-5-O-phosphono-beta-D-erythro-pentofuranosylamine 0.808 5 MF7 N-{2-amino-5-[formyl(methyl)amino]-6-hydroxypyrimidin-4-yl}-2-deoxy-5-O-phosphono-beta-D-erythro-pentofuranosylamine 0.778