Studies on heterocyclic compounds. 6. Synthesis and analgesic and antiinflammatory activities of 3,4-dimethylpyrano[2,3-c]pyrazol-6-one derivatives

Abstract

A series of new 1- and 2-substituted 3,4-dimethylpyrano[2,3-c]pyrazol-6-one derivatives and 1-substituted 1,6-dihydro-4-methyl-6-oxopyrano[2,3-c]pyrazole-3-acetic acids were synthesized and examined for their analgesic and antiinflammatory activities. Most of these compounds showed more prominent analgesic activities than antiinflammatory activities, and this result was similar to that of aminopyrine. Among these compounds, 1,3,4-trimethylpyrano[2,3-c]pyrazol-6(1H)-one and 2,3,4-trimethylpyrano[2,3-c]pyrazol-6(2H)-one showed more potent analgesic activity than aminopyrine.