Synthesis and determination of acute and chronic pain activities of 1-1-(3-methylphenyl) (tetralyl)piperidine as a new derivative of phencyclidine via tail immersion and formalin tests.
Phencyclidine (1-(1-phenylcyclohexyl)piperidine, CAS 956-90-1, PCP, 1) and ketamine (2-O-chlorophenyl-2-methylaminocyclohexan, CAS 1867-66-9, II) revealed some analgesic effects. Some of their derivatives have been synthesized for biological properties studies. Utilizing 1-tetralone as a starting material, 1-1-(3-methylphenyl)(tetralyl)piperidine, (PCP-CH3-tetralyl, III) was synthesized and its analgesic effects were studied on rats via tail immersion (as a model of acute thermal pain) and formalin (as a model of acute chemical and chronic pain) tests and compared with those of ketamine and PCP. The results indicated a marked anti-nociception 2-25 min after ketamine injection, but this analgesic effect lasted for 40 min following PCP-CH3-tetralyl application in the tail immersion test. However, the data obtained from the formalin test showed that chronic pain could be significantly attenuated by ketamine, PCP and PCP-CH3-tetralyl.