Levodopa dopamine synthesis with

Dopamine is the immediate precursor in the synthesis of norepinephrine (see Figure 6-5). Its cardiovascular effects were described above. Endogenous dopamine may have more important effects in regulating sodium excretion and renal function. It is an important neurotransmitter in the central nervous system and is involved in the reward stimulus relevant to addiction. Its deficiency in the basal ganglia leads to Parkinson s disease, which is treated with its precursor levodopa. Dopamine receptors are also targets for antipsychotic drugs. 

Enantioselective synthesis is particularly important in the pharmaceutical industry, because only one enantiomer of a chiral drug is likely to have the desired effect. For example, levodopa [(- )-dopa or Z-dopa] is used in patients with Parkinson s disease to counteract a deficiency of dopamine, one of the neurotransmitters in the brain. Dopamine... 

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