Dihydroxyphenylalanine - ț̢
A beta-hydroxylated derivative of phenylalanine. The D-form of dihydroxyphenylalanine has less physiologic activity than the L-form and is commonly used experimentally to determine whether the pharmacological effects of LEVODOPA are stereospecific.
Dihydroxytryptamines - ț̢
Tryptamine substituted with two hydroxyl groups in any position. Some are cytotoxic serotonin analogs that are preferentially taken up by serotonergic neurons and then destroy those neurons.