Patent ID: 8889701

Claim:
A compound selected from a (2R,3R,5R)-3-hydroxy-(5-pyrimidin-1-yl)tetrahydrofuran-2-yl)methyl aryl phosphoramidate of formula 1 or a (5)-(2R,3R,5R)-3-hydroxy-(5-pyrimidin-1-yl)tetrahydrofuran-2-yl)methyl aryl phosphoramidate of formula 2, or a pharmaceutically acceptable salt, a hydrate, a crystalline form or a stereoisomer thereof, wherein: R 1 is (i) hydrogen, (CH 3 ) 2 [(CH 3 ) 3 C]Si, a C 2 -C 6 acyl, optionally substituted with NR 5 R 6 group, wherein R 5 and R 6 are independently hydrogen or a C 1 -C 4 alkyl; or (ii) 1-pyrrole-2-ylcarbonyl, piperidin-3-ylcarbonyl or piperidin-4-ylcarbonyl; R 2 and R 3 are F; or R 3 is CH 3 and R 2 is F or OH; R 4 is hydrogen or methyl; Ar is a phenyl, a pyridyl or a naphthyl, wherein phenyl, pyridyl or naphthyl are optionally substituted with at least one of C 1-3 alkyl, C 2-4 alkenyl, C 2-4 alkynyl, C 1-3 alkoxy, F, Cl, Br, I, nitro, cyano, or —N(C 1-3 alkyl) 2 ; Pm is 2,4-dioxo-3,4-dihydro-2H-pyrimidin-1-yl or 4-(4-amino-2-oxo-2H-pyrimidin-1-yl), in which amino group is optionally substituted with 1-pyrrole-2-ylcarbonyl, piperidin-3-ylcarbonyl, piperidin-4-ylcarbonyl or radical C(O)R 8 , wherein R 8 is (i) a C 1 -C 4 alkyl, optionally substituted with NR 6 R 7 group, wherein R 6 and R 7 are independently hydrogen or C 1 -C 4 alkyl; or (ii) a C 1-3 alkoxy optionally substituted with a phenyl; X is O or N—R 9 , wherein R 9 is a C 1 -C 4 alkyl, optionally substituted with OH or OCH 3 ; n=1, 2 or 3.