Systematic Optimization of Meta-Halogenated 18 F-Benzylguanidine Derivatives for PET Imaging of Cardiac Sympathetic Innervation

Benzylguanidine, a norepinephrine analogue with high NET affinity, serves as a promising scaffold for visualizing cardiac sympathetic function. This study investigated whether ¹⁸F-labeled benzylguanidine derivatives with systematical <i>meta</i>-halogen substitution could be optimized for PET imaging of cardiac sympathetic innervation. Five derivatives were radiolabeled efficiently with high purity and stability, and aromatic substitution markedly affected in vitro and in vivo. Among