ANALGESICS

摘要

The invention provides an analgesic composition comprising as an active ingredient at least one pyrazoloÄ1,5-aÜpyrimidine derivative of the following formula (1): <CHEM> wherein R<11> represents hydrogen, lower alkyl, pyridyl, furyl, thienyl, phenyl optionally having lower alkyl or phenylthio as a substituent, N-(lower)alkylpyrrolyl or pyrazinyl; R<12> represents hydrogen, halogen, phenyl, phenyl having halogen, phenylthio or trifluoromethyl as a substituent, phenyl having trifluoromethyl and nitro as substituents, or phenyl having lower alkoxy and phenylthio as substituents; R<13> represents hydrogen, lower alkyl optionally having oxo, ethylenedioxy, lower alkanoyloxy, lower alkoxy, lower alkylthio, carboxyl, halogen or thienyl as a substituent, lower alkenyl, cycloalkyl, or phenyl optionally having 1 to 3 substituents selected from the group consisting of lower alkyl, halogen and lower alkoxy, furyl or thienyl; R<14> represents hydrogen, carboxyl, lower alkoxycarbonyl, nitro, halogen, or lower alkyl having lower alkoxycarbonyl or the residue of an alkali metal salt of carboxylic acid as a substituent; R<13> and R<14> may conjointly form lower alkylene; R<15> represents hydrogen, alkali metal, lower alkyl, phenyl optionally having 1 to 3 substituents selected from the group consisting of lower alkyl and lower alkoxy, pyridyl optionally having lower alkyl or halogen as a substituent, quinolyl or isoquinolyl; and A represents a single bond or lower alkylene. This composition exhibits potent analgesic activity and is effective for alleviating various types of pain such as postoperative pain.