Naftopidil (INN, marketed under the brand name Flivas) is a drug used in benign prostatic hyperplasia which acts as a selective ñ<sub>1</sub>-adrenergic receptor antagonist or alpha-1 blocker.
The reaction of 1-naphthol (1) with epichlorohydrin (2) in the presence of alkali gives the epoxide (3). Alkylation of the piperazine derivative (4) yields naftopidil.