Combined analgesic/neuroleptic activity in N-butyrophenone prodine-like compounds

Some 4-phenyl-4-piperidinols, corresponding esters, and related compounds with a p-fluorobutyrophenone chain on nitrogen were synthesized and evaluated in in vitro and in vivo tests in order to examine their ability to interact contemporaneously with opioid and dopamine receptors. The propionyloxy derivatives showed a good combination of analgesic and neuroleptic activity. With a 3-methyl substituent on the piperidine ring, the beta-configuration was the more active form not only for analgesic activity, as expected from previous results on prodines, but also for neuroleptic activity. Haloperidol and its propionate were also tested as reference compounds.