QSAR study of 125I-labeled 2-(4-aminophenyl)benzothiazole derivatives as imaging agents for β-amyloid in the brain with Alzheimer’s disease

Abstract

In order to develop small molecular probes for imaging of Aβ plaques in the brain with Alzheimer’s disease, four benzothiazole derivatives as Aβ probes, 3’-125I-BTA, 3’-125I-CBTA, 3’-125I-BTA-Ac, and 3’-125I-CBTA-Ac were successfully prepared. The four probes displayed the following initial brain uptake: 10.28 %ID/g, 3.62 %ID/g, 3.33 %ID/g and 3.71 %ID/g at 2-minute post iv injection, respectively. The study of quantitative structure-activity relationship (QSAR) indicated that the initial brain uptake was correlated with molecule volume (Vm) and dipole moment (Dp), but the Dp was the main factor. 3’-125I-BTA has the highest initial brain uptake among the four Aβ probes because of the smallest Dp.