3d image of levodopa skeletal formula

l-dopa levodopa l-3 4-dihydroxyphenylalanine amino acid tyrosine precursor neurotransmitters dopamine norepinephrine noradrenaline epinephrine adrenaline catecholamines psychoactive drug treatment parkinson's disease dopamine-responsive dystonia chirality isomer enantiomeric purity levodopa parkinson medicament thin-layer chromatography blood-brain barrier parkinson-plus syndrome parkinsonism bradykinesia rigidity tremors swallowing disorders central nervous system dopa decarboxylase tyrosine hydroxylase dietary supplement marine adhesion adhesive protein mussels age-related macular degeneration amd rendering metabolite metabolism neuroscience medication side effect pathway path biosynthetic intermediate