Seventeen 2-aryl-3-haloallylamine derivatives were prepared and evaluated as inhibitors of monoamine oxidase (MAO, EC 1.4. 3.4). The synthesis of these compounds was achieved from either a-methylstyrene or ring-substituted phenylacetic acid derivatives. With one exception, these 2-arylallylamines were found to be enzyme-activated, irreversible inhibitors of MAO. The most potent inhibitors were ring-substituted derivatives of (E)-2-phenyl-3- ...