Acyclic purine nucleoside analogue Acyclic purine nucleoside analogue Acyclic purine nucleoside analogue Acyclic purine nucleoside analogue Acyclic purine nucleoside analogue Acyclic purine nucleoside analogue Acyclic purine nucleoside analogue Acyclic purine nucleoside analogue Acyclic purine nucleoside analogue Acyclic purine nucleoside analogue Acyclic purine nucleoside analogue Acyclic purine nucleoside analogue Acyclic purine nucleoside analogue