3-Hydroxy-piperidinyl-N-benzyl-acyl-arylhydrazone derivatives reduce neuropathic pain and increase thermal threshold mediated by opioid system.

Here in, we report the preparation and evaluation of four 3-hydroxy-piperidine-N-benzyl-aryl-acylhydrazone derivatives (6a-d) for their potential antinociceptive activity. In the tail flick test, compounds 6a and 6d exhibited a significant increase in the latency time of the animals, in comparison to the control group. These two compounds also showed a significant increase in the nociceptive threshold from 1 to 6 h after treatment in the CCI neuropathic pain model. In both cases, the antinociceptive activity was blocked by naloxone, suggesting an opioid mechanism of action, but without sedative or motor coordination effects.