Synthesis and Evaluation of Novel Chalcone Derivatives with ^99mTc/Re Complexes as Potential Probes for Detection of β-Amyloid Plaques.

ABSTRACT
Four ^99mTc-labeled chalcone derivatives and their corresponding rhenium analogues were tested as potential probes for imaging β-amyloid plaques. The chalcones showed higher affinity for Aβ(1-42) aggregates than did ^99m Tc complexes. In sections of brain tissue from an animal model of AD, the four Re chalcones intensely stained β-amyloidplaques. Inbiodistributionexperiments using normal mice, ^99mTc-BAT-chalcone ([^99mTc]17) displayed high uptake in the brain (1.48% ID/g) at 2 min postinjection. The radioactivity washed out from the brain rapidly (0.17% ID/g at 60 min), a highly desirable feature for an imaging agent. [^99mTc]17 may be a potential probe for imaging β-amyloid plaques in Alzheimer’s brains.