Synthesis and biological evaluation of 99mTc, Re-monoamine-monoamide conjugated to 2-(4-aminophenyl)benzothiazole as potential probes for β-amyloid plaques in the brain

The synthesis and biological evaluation of 99mTc, Re-MAMA-BTA were reported here. The benzothiazole aniline (BTA) conjugated with monoamine-monoamide (MAMA) was synthesized and then labeled with 99mTc. Its corresponding rhenium analogue was synthesized, and the fluorescent staining was performed in brain sections of both Tg mouse and Alzheimer’s disease (AD) patient. The fluorescent rhenium complex Re-MAMA-BTA selectively bound to the amyloid aggregates in the brain sections of both APP Tg mouse and AD patient. The analogous 99mTc-MAMA-BTA complex could enter the normal mouse brain with high initial uptake. These results are encouraging for further exploration of their derivatives as imaging agents for Aβ plaques in the brain.