5'-Iodo-N2-isobutyryl-2′-deoxyguanosine

5′-Iodo-N²-isobutyryl-2′-deoxyguanosine is a 5′-halogenated derivative of N²-isobutyryl-2′-deoxyguanosine, in which the 5′-hydroxyl group is formally replaced by iodine to introduce a potential leaving group for downstream functionalization. The parent nucleoside, N²-isobutyrylguanosine, is widely used as a protected guanine building block in cap analog synthesis, where the isobutyryl group masks the exocyclic N²-amino function during multistep modification strategies.¹