| abstract |
The present invention relates to compounds of formula I: n n n n n n n n n n for use in treating pulmonary arterial hypertension and associated conditions, where R 1 , R 2 and R 3 are the same or different and signify hydrogens, halogens, alkyl, alkylaryl, alkyloxy, hydroxy, nitro, amino, alkylcarbonylamino, alkylamino or dialkylamino group; R 4 signifies hydrogen, alkyl, -alkylaryl or -alkylheteroaryl; X signifies CH 2 , oxygen atom or sulphur atom; n is 1, 2 or 3, with the proviso that when n is 1, X is not CH 2 ; and the individual (R)- and (S)-enantiomers or mixtures of enantiomers and pharmaceutically acceptable salts thereof. |