Oxyalkyne compounds corresponding to the formula I ##STR1## in which the substituent Y in the meta- or para-position is R.sup.1 represents CH.sub.3 or NH.sub.2, R.sup.2 represents H or CH.sub.3, R.sup.3 represents H, C.sub.1-3 -alkyl or COCH.sub.3, and Ar represents an aromatic residue selected from the group ##STR2## with the proviso that the substituents R.sup.4, R.sup.5 and R.sup.6 are the same or different and each substituent represents H, F, Cl, Br, C.sub.1-6 -alkyl, CF.sub.3 or C.sub.1-6 -alkoxy, and R.sup.7 represents H, F, Cl, Br, C.sub.1-3 -alkyl or CF.sub.3,in the form of their racemates or mixtures of diastereoisomers or in optically active form, which are suitable active ingredients in pharmaceutical compositions.