Abstract: The invention relates to compounds of the general formula I ##STR1## wherein R.sub.1 represents one up to and including four, the same or different substituents selected from alkyl(1-6 C), alkoxy(1-6 C), hydroxy, halogen, NO.sub.2, CF.sub.3 or the group --NR.sub.5 R.sub.6, whereby two substituents taken together may also represent a methylene-dioxy group,X represents nitrogen or the group ##STR2## n has the value 0, 1 or 2, R.sub.3 represents one of the moieties: ##STR3## the latter meaning of R.sub.3 (amide) only under the condition that for X is nitrogen the meaning of R.sub.1 is limited to substituents selected from hydroxy, alkoxy(1-6 C) and methylenedioxy, and R.sub.4, R.sub.5 and R.sub.6 represent hydrogen or alkyl(1-6 C), and pharmaceutically acceptable salts thereof, suitable in the treatment of heart failure.

Abstract: The invention relates to compounds of the general formula I ##STR1## wherein R.sub.1 represents one up to and including four, the same or different substituents selected from alkyl(1-6 C), alkoxy(1-6 C), hydroxy, halogen, NO.sub.2 CF.sub.3 or the group --NR.sub.5 R.sub.6, whereby two substituents taken together may also represent a methylene-dioxy group,X represents nitrogen or the group ##STR2## n has the value 0, 1 or 2, R.sub.3 represents one of the moieties: ##STR3## the latter meaning of R.sub.3 (amide) only under the condition that for X is nitrogen the meaning of R.sub.1 is limited to substituents selected from hydroxy, alkoxy(1-6 C) and methylenedioxy, and R.sub.4, R.sub.5 and R.sub.6 represent hydrogen or alkyl(1-6 C), and pharmaceutically acceptable salts thereof, suitable in the treatment of heart failure.