| abstract |
(57) [Summary] Formula (I) Wherein R is a methylene group, N-alkyl, NH or an oxygen atom or a sulfur atom, R 1 and R 2 are the same or different, and are a hydrogen atom or a halogen atom or a hydroxy group, an alkoxy group, an alkyl Group, nitro group, amino group, monoalkylamino group, dialkylamino group, cyano group, polyfluoroalkyl group, polyfluoroalkoxy group or phenoxy group, R 3 and R 4 are the same or different, and a hydrogen atom or a halogen atom or alkyl And tautomeric forms thereof, salts thereof, preparation thereof and drugs containing the above-mentioned derivatives. |