Patent Evaluation: κ-Opioids as Potent Analgesics

Summary

Novelty: A novel series of azacyclic k-agonists are claimed and are said to be of use in the treatment of pain and cerebral ischaemia.

Biology: Data are given for a number of compounds in two analgesic tests, the mouse writhing assay (ED₅₀ values in the range 0.005–0.299 mg/kg sc) and the mouse tail-flick (ED₅₀ values in the range 0.052–10 mg/kg sc).

Biology: Experimental and physical data are given on a number of examples, some of which are optically pure. Sixteen compounds are named within the claims, the most active in the tail-flick model is (2S)-1-(4-trifluoromethylphenyl)acetyl-2-[N-methyl-N-(2-fluoroethyl)]-aminomethyl piperidine hydrochloride.

Structure: