New phthalimide derivatives with potent analgesic activity: II

Seven new phthalimide derivatives (9a~g) with 1,2,4-oxadiazol-5-yl methyl group attached to nitrogen have been synthesized from N-phthaloyglycine 6 and arylamidoximes 7a~g. All of these showed potent analgesic effect with acetic acid induced “writhing” test in mice. One of the better compounds (ID50 = 2.2. mg/Kg ip) has been found to be 9a which also demonstrates analgesic activity against inflammatory pain.