Benztropine
Benztropine, with the chemical formula 3alpha-diphenylmethoxytropane, is a tropane-based dopamine inhibitor used for the symptomatic treatment of Parkinson's disease. It is a combination molecule between a tropane ring, similar to cocaine, and a diphenyl ether from the dialkylpiperazines determined to be a dopamine uptake inhibitor since 1970. The generation of structure-activity relationships proved that benztropine derivatives with the presence of a chlorine substituent in the para position in one of the phenyl rings produces an increased potency for dopamine uptake inhibition as well as a decreased inhibition of serotonin and norepinephrine. Benztropine was developed by USL Pharma and officially approved by the FDA on 1996.