Piroheptine (brand name Trimol) is an anticholinergic and antihistamine used as an antiparkinsonian agent.
Piroheptine was observed to prevent the reuptake of dopamine and is therefore a DRI.
Piroheptine comes from a family of drugs that includes pridefine and etifelmine.
Piroheptine can be synthesized starting from 5-(3-bromopropylidene)-10,11-dihydro-5H-dibenzo[a,d]cycloheptene (1) and acetonitrile which react via catalysis by stannic chloride (SnCl<sub>4</sub>) to give 2-methyl-3-(10,11-dihydro-5H-dibenzo[a,d] cycloheptene-5-ylidene)-1-pyrroline (2). Quaternization of the product with ethyl iodide affords the alkyl immonium ion (3). Reduction of the Schiff base with sodium borohydride then affords the product, piroheptine (4).