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Updated: Aug 26, 2026

Microwave-Assisted Preparation of 1-Aryl-1H-pyrazole-5-amines
Published on: June 23, 2019
3-(4-phenoxyphenyl)pyrazoles: a novel class of sodium channel blockers
Ji Yang1, Parviz Gharagozloo, Jiangchao Yao
1Discovery Research, Purdue Pharma L.P., 6 Cedar Brook Drive, Cranbury, New Jersey 08512, Novartis. ji.yang@pharma.com
Abstract:
A series of 3-(4-phenoxyphenyl)-1H-pyrazoles were synthesized and characterized as potent state-dependent sodium channel blockers. A limited SAR study was carried out to delineate the chemical requirements for potency. The results indicate that the distal phenyl group is critical for activity but will tolerate lipophilic (+pi) electronegative (+sigma) substituents at the ortho and/or para position. Substitution at the pyrazole nitrogen with a H-bond donor improves potency. Compound 18 showed robust activity in the rat Chung neuropathy paradigm.
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