Novel 4-benzyl-1-(2H)-phthalazinone derivatives containing an amino acid radical

摘要

Antiasthmatic compounds of the formula <IMAGE> in which R1 denotes hydrogen, fluorine, chlorine, bromine, trifluoromethyl, C1-C6-alkyl or C1-C6-alkoxy, and the radical A represents the group <IMAGE> in which R3 denotes hydrogen, a phenyl radical, an indol-3-ylmethyl radical or imidazol-4-ylmethyl radical, or a C1-C10-alkyl group or in which R3 denotes a C1-C10-alkyl group which is substituted by a carboxyl group, a C1-C6-alkoxycarbonyl group, an aminocarbonyl group, a hydroxyl group, a C1-C6-alkoxy group, a C2-C6-alkanoyloxy group, a mercapto group, a C1-C6-alkylthio group, a C2-C6-alkanoylmercapto group, a phenyl group, a hydroxyphenyl group, a dihydroxyphenyl group, an amino-C1-C6-alkylthio group, an amino-C1-C6-alkoxy group, an amino group, a ureido group (H2NCONH-) or a guanidino group, or in which R3 together with the structural moiety >CH(NHR4) represents the pyrrolidin-2-yl radical (proline radical) or the 4-hydroxypyrrolidin-2-yl radical, R4 denotes hydrogen, benzyl or a C1-C6-alkyl radical, R5 denotes hydrogen, benzyl, a C1-C6-alkyl radical, a C2-C6-alkanoyl radical or the group <IMAGE> and R6 is hydrogen, benzyl or C2-C6-alkanoyl, and processes for their preparation.