Structure–activity relationships of novel iodinated quinoline-2-carboxamides for targeting the translocator protein

Abstract

In an effort to develop a new SPECT imaging agent for the translocator protein (TSPO), a series of novel iodinated quinoline-2-carboxamides have been synthesised and evaluated for binding affinity using rat brain homogenates. The outcome of the biological testing in combination with HPLC determination of the physicochemical properties of these compounds directed the design of new analogues resulting in 4-(2-iodophenyl)quinoline-2-N-diethylcarboxamide, a new TSPO ligand with higher affinity than the widely used clinical imaging agent PK11195.