| abstract |
Disclosed are compounds of general formula (I), wherein R1 is H or halogen, such as Cl or F, C1-4 alkyl or C1-4 alkoxyl with linear or branched chain, R2, R3 and R4 independently are H or linear, branched or cyclic C1-4 alkyl and R5 is H, C1-2 alkyl, C1-2 fluoroalkyl, C1-2 perfluoroalkyl, in the form of enantiomers or diastereomers or in the form of mixtures of these various form, including racemic mixtures as well as in the form of additive salts with pharmaceutically acceptable acids. The said derivatives are therapeutically usable. |