The synthesis of some 5-substituted 4-isoxazoleacetic acids starting f
rom 5-substituted 4-isoxazolemethanols via their conversion to 4-(brom
omethyl)isoxazoles, 4-isoxazoleacetonitriles and acid hydrolysis of th
e latter is described. 5-Ethyl- and 5-propyl-4-isoxazoleacetic acids s
howed in the writhing test an analgesic activity comparable to that of
aspirin.