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To harness radiometals in clinical settings, a chelator forming a stable complex with the metal of interest and targets the desired pathological site is needed. Toward this goal, we previously reported a unique set of chelators that can stably bind to both large and small metal ions, via a conformational switch. Within this chelator class, py‐macrodipa is particularly promising based on its ability to stably bind several medicinally valuable radiometals including large^132/135La³⁺,²¹³Bi³⁺, and small⁴⁴Sc³⁺. Here, we report a 10‐step organic synthesis of its bifunctional analogue py‐macrodipa‐NCS, which contains an amine‐reactive −NCS group that is amenable for bioconjugation reactions to targeting vectors. The hydrolytic stability of py‐macordipa‐NCS was assessed, revealing a half‐life of 6.0 d in pH 9.0 aqueous buffer. This bifunctional chelator was then conjugated to a prostate‐specific membrane antigen (PSMA)‐binding moiety, yielding the bioconjugate py‐macrodipa‐PSMA, which was subsequently radiolabeled with large^132/135La³⁺and small⁴⁷Sc³⁺, revealing efficient and quantitative complex formation. The resulting radiocomplexes were injected into mice bearing both PSMA‐expressing and PSMA‐non‐expressing tumor xenografts to determine their biodistribution patterns, revealing delivery of both^132/135La³⁺and⁴⁷Sc³⁺to PSMA+ tumor sites. However, partial radiometal dissociation was observed, suggesting that py‐macrodipa‐PSMA needs further structural optimization.