The invention relates to novel compounds of the general formula (I), ##STR1## wherein R means hydrogen or a straight or branched chain C.sub.1-6 alkoxy group;R.sup.1 stands for hydrogen or a straight or branched chain C.sub.1-6 alkyl group;R.sup.2 represents hydrogen or a straight or branched chain C.sub.1-6 alkyl group;R.sup.3 means hydrogen, a straight or branched chain C.sub.1-6 alkyl group optionally substituted by one or two hydroxyl and/or one or two straight or branched chain C.sub.1-4 alkoxy group(s); or a C.sub.4-7 cycloalkyl group;R.sup.4 stands for hydrogen or a straight or branched chain C.sub.1-6 alkyl group optionally substituted by one or two hydroxyl and/or one or two straight or branched chain C.sub.1-4 alkoxy group(s); or a C.sub.4-7 cycloalkyl group; orR.sup.3 and R.sup.4 together with the nitrogen atom, to which they are attached form a 4 to 8-membered cyclic group of formula ##STR2## optionally substituted by one or two straight or branched chain C.sub.1-4 alkoxy and/or one or two straight or branched chain C.sub.1-4 alkyl group(s), where optionally an oxygen or sulfur atom or an N-R.sup.5 group may be substituted for a ring carbon atom, where R.sup.5 means hydrogen or a straight or branched chain C.sub.1-6 aliphatic alkyl group, the 4- to 8-membered cycle optionally being condensed with a benzene ring;R.sup.6 stands for hydrogen or a C.sub.1-10 acyl group and the salts and hydrates thereof as well as pharmaceutical compositions containing these compounds.The compounds of the invention antagonize the effects of constrictive mediators, e.g. histamine, acetylcholine or serotonin; they show an antiallergic action and possess an antiinflammatory effect. Thus, these compounds can therapeutically be used as bronchodilators as well as antiallergic or antiinflammatory drugs, particularly in the treatment of bronchial asthma.