9H-Purin-6-amine, 9-[(2ξ)-5-O-[hydroxy[[hydroxy[(3S)-3-hydroxy-2,2-dimethyl-4-oxo-4-[[3-oxo-3-[[2-[(1-oxooctyl)thio]ethyl]amino]propyl]amino]butoxy]phosphinyl]oxy]phosphinyl]-3-O-phosphono-β-D-thr eo-pentofuranosyl]-, ion(4-)