The replacement of amide bonds in the backbone of peptides by proteolytically stable 1, 2, 3- triazole isosteres can provide novel peptidomimetics with promising properties for the development of tumor-targeting radiopeptides. On the basis of our previous work with radiolabeled agonistic bombesin (BBN) derivatives of the sequence [Nle14] BBN (7–14), we substituted selected amide bonds of the structurally closely related antagonistic peptide ...