A process for the preparation of a compound of formula ##STR21## wherein R.sub.1 is H, CH.sub.3, OCH.sub.3, NO.sub.2, NH.sub.2, CN, CF.sub.3, CHF.sub.2, CH.sub.2 F or halogen, R.sub.2 is 1,2,4-triazolyl R.sub.6 is methylene or ethylene;
- or a stereoisomer;
- or a non-toxic pharmaceutically acceptable acid addition salt thereof which comprises reacting a compound of formula ##STR22## wherein R.sub.7 is CN or a functional group which may be converted to CN, with an ester of formula ##STR23## wherein R' is lower alkyl and n is 1 or 2, in the presence of a strong base, to give a compound of formula ##STR24## and further reducing this compound to give a compound of formula ##STR25## and converting R.sub.7 when not CN to CN and deprotecting the optional N-protection of the heterocyclyl group, and if desired separating and/or isolating stereoisomers thereof and/or converting the compounds of the invention to their non-toxic pharmaceutically acceptable acid addition salts or converting the acid addition salts to free compounds.