817682.fig.003
Figure 3: Chemical structures of RGD tracers. 18F-labeled galacto-RGD [6], NOTA-RGD [7], and cyclic RGD peptide dimers (E [c(RGDfK)]2, E [c(RGDyK)]2, [c(RGDfE)HEG]2-K-Dpr-[18F]FBOA, DOTA-E-[c(RGDfK)]2), and PEG4-dimer) [812].