Sc(III) Complexes of Pyclen Derivative Ligands as Probes for Hypoxia: Synthesis, Chemical Characterization, ⁴⁴Sc-Radiolabeling, and Preclinical Assessment.

ABSTRACT: Rigid pyclen derivative ligands bearing hypoxia-sensitive nitroimidazole (NI) pendants, PC2A-Ph-NI (hexadentate) and PC2AM-NI (heptadentate), were synthesized, radiolabeled with ⁴⁴Sc(III), and evaluated under preclinical circumstances. Physicochemical characterization was carried out using the structurally related model ligand, PC2AM^nBu, by multinuclear NMR, UV-Vis spectroscopy, and pH-potentiometry. Sc(III) ion was found to form a stable complex with PC2AM^nBu (log K_ScL = 19.53(4); pSc = 19.32), in a reasonably fast reaction, with outstanding inertness (t_1/2 = 529 hours in 1 M HClO₄). The [Sc(PC2AM^nBu)]⁺ complex can coordinate fluoride (log K_ScLF = 2.5(2)), and the ternary complex is remarkab

SUBMITTER: Csupasz T 

PROVIDER: S-EPMC12731536 | biostudies-literature | 2025 Dec

REPOSITORIES: biostudies-literature