132723-00-3 2'F-ddA-N-oxide 9-(2',3'-Dideoxy-2'-fluoro-.beta.-D-arabino-furanosyl)adenine-1-oxide 9H-Purin-6-amine, 9-(2,3-dideoxy-2-fluoro-.beta.-D-threo-pentofuranosyl)-, 1-oxide AIDS-002826 AIDS002826 NSC628173