(S)-2-amino-4-(((3R,4S,5R)-3-(6-amino-9H-purin-9-yl)-4,5-dihydroxycyclopent-1-enyl)methoxy)butanoic acid

9-((3aS,4R,6aR)-6-((2-((2S,5R)-3,6-diethoxy-5-isopropyl-2,5-dihydropyrazin-2-yl)ethoxy)methyl)-2,2-dimethyl-4,6a-dihydro-3aH-cyclopenta[d][1,3]dioxol-4-yl)-9H-purin-6-bis(tert-butoxylcarbonyl)amine