Derivatives of 3-aminopropane-1,2-diol

A compound of the formula ##STR32## in which Ar is unsubstituted or substituted phenyl, naphthyl, 1,2,3,4-tetrahydro-5-naphthyl, pyridyl, pyridazinyl, pyrimidinyl, pyrazinyl, thienyl, thiazolyl, thiadiazolyl, indolyl, quinolinyl, isoquinolinyl, [3,4-dihydro-2-(1H)-quinolinolyl,][2-oxo-benzimidazol-4-yl,]naphthyridinyl or benzofuranyl, and where said group Ar is substituted there are one or at most three substituents selected from lower alkyl, lower alkenyl or lower alkoxy, lower alkenyloxy, lower alkynyl, lower alkynyloxy, cyano and/or nitro, and/or, as substituents bonded directly or to the above-mentioned lower alkyl, lower alkenyl or lower alkoxy, one or more of lower alkanoyl, cycloalkyl, lower alkoxycarbonyl, carbamoyl, lower alkylcarbamoyl, di-lower alkylcarbamoyl or (hydroxy-lower alkyl)-carbamoyl, lower alkylsulphinyl, lower alkylsulphonyl, sulphamoyl or lower alkylsulphamoyl;

• or halogen bonded directly to said group Ar, or halogen bonded to said lower alkyl or, in a position higher than the 1-position, halogen bonded to said lower alkoxy;
• or hydroxy, bonded directly or bonded to said lower alkyl;
• as substituents not bonded directly to said group Ar, lower alkoxy, cycloalkyl-lower alkoxy, phenyl-lower alkoxy, lower alkanoyloxy, lower alkylthio, amino, lower alkylamino, di-lower alkylamino, alkyleneamino or oxa-alkyleneamino, pyrrol-1-yl, lower alkanoylamino, lower alkoxycarbonylamino, ureido, ureido substituted by one or two lower alkyl, by hydroxy-lower alkyl or by cycloalkyl or lower alkylsulphonylamino, n is the number 0 or 1;
• alk is alkylene having from 2 to 4 carbon atoms, the nitrogen atom and the oxygen atom or, if n is zero, the phenyl radical being separated from one another by 2 or 3 carbon atoms, and R.sub.1 and R.sub.2 independently represent hydrogen or lower alkyl, or together represent piperidino, or pharmaceutically acceptable, non-toxic acid addition salts thereof.