New analgesics derived from the phencyclidine analogue thienylcyclidine.

Several derivatives of thienylcyclidine (1-[1-(2-thienyl)cyclohexyl]piperidine, CAS 1867-65-8, TCP) were synthesized and characterized. The compounds were evaluated for analgesic agonism in mice using tail-flick test as a model for antinociceptive activity. The most potent compounds are 7 and 11, which are about twice as active as the standard pethidine. The influence of naloxone on the antinociceptive activity of these compounds is also reported. The present pharmacological data are discussed and compared with those previously reported for structurally related phencyclidine analgesics.