Disclosed here in are compounds and methods of diagnosing Alzheimer's Disease or a predisposition thereto in a mammal, the method comprising administering to the mammal a diagnostically effective amount of a radiolabeled compound, wherein the compound is selected from the group consisting of radiolabeled flavones, coumarins, carbazoles, quinolinones, chromenones, imidazoles and triazoles derivatives, allowing the compound to distribute into the brain tissue, and imaging the brain tissue, wherein an increase in binding of the compound to the brain tissue compared to a normal control level of binding indicates that the mammal is suffering from or is at risk of developing Alzheimer's Disease.