Phencyclidine (1-(1-phenylcyclohexyl) piperidine, PCP, I) and ketamine (2-O-chlorophenyl-2-methylaminocyclohexan, II) have shown analgesic effects. Some of its derivatives were synthesized and their biological properties have been studied. In this study, a new derivative of PCP, (1-[1-(3-methoxyphenyl) (tetralyl)] piperidine, PCP-OCH3-tetralyl, III) was synthesized and the acute thermal pain of this compound was determined using tail immersion test on rats and the results were compared with Ketamine and PCP. The results indicated a marked anti-nociception 2-25 min after ketamine injection, but the analgesic effect remained for 40 min following PCP-OCH3-tetralyl application in tail immersion test. However, the data obtained from formalin test showed that the chronic anti-nociception effect of ketamine was higher than PCP and PCP-OCH3-tetralyl exhibited almost similar analgesic effect.
Keywords: 1-Tetralone derivatives; Acute and chronic pain; Formalin test; Ketamine; Phencyclidine; Tail immersion test.