1-(2,3-Dideoxy-2-fluoro-.beta.-D-threo-pentofuranosyl)-cytosine 128496-09-3 2',5diF-dd-araC 2'5-Difluoro-2',3'-dideoxyarabinosylcytosine 2(1H)-Pyrimidinone, 4-amino-1-(2,3-dideoxy-2-fluoro-.beta.-D-threo-pentofuranosyl)-5-fluoro- AIDS-001465 AIDS001465