D-DOPA

-DOPA 'dextrodopa') is similar to , but with opposite chirality. Levo- and dextro- rotation refer to a molecule's ability to rotate planes of polarized light in one or the other direction. Whereas is moderately effective in the treatment of Parkinson's disease and dopamine-responsive dystonia by stimulating the production of dopamine in the brain, is biologically inactive.
Avoiding unwanted production of D-DOPA is a goal for commercial synthesis of -based drugs to treat Parkinson's disease.