Synthesis and biological evaluation of 99mTc labeled aryl piperazine derivatives as cerebral radiotracers

Expanding the Cyclopentadienyl Framework: 99mTc/Re Complexes with Orthogonal Functions for Bioconjugation

“…Therefore, they are a class of compounds attractive for the development of biologically compatible imaging agents. Since the early 1990s, [Cp-R 99m Tc­(CO) 3 ]-type complexes have been employed in the development of radiotracers for SPECT imaging. , Cytectrene complexes were employed to image various targets such as the central nervous system, the myocardium, cancer, and infection sites . The Re homologues were developed for therapeutic applications, thereby rendering the employed ligand systems and their complexes theranostic (applicable for both therapy and diagnostics).…”

“…Although several synthetic approaches to cytectrenes were reported, the majority of cytectrenes are still synthesized by the DLT strategy. − The DLT reaction conditions generally include high temperatures, the use of strong Lewis acids, and organic solvents. This strategy is therefore not compatible with most biomolecules, since their functional groups and tertiary protein structures do not tolerate such harsh conditions.…”

Convenient Cyclopentadiene Modifications for Building Versatile (Radio‐)Metal Cyclopentadienyl Frameworks

“…The first derivative ( 7) was inspired by cytectrene [ 99m Tc]5, which was reported by Zenati et al in 2017 for brain imaging. [9] The structure of the second derivative (8) had its origin in cytectrene [ 99m Tc]6, a compound developed by Li et al in 2018 for the imaging of multi-drug resistance (MDR) in cancer cells. [10] Phosphonium compounds also showed application in targeting mitochondria.…”