A group of heterocyclic compounds generally exhibiting central nervous system activity (such as depressant and anti-convulsant activities) and, in some cases, cardiovascular and/or anti-inflammatory activity are described. The compounds have the formula ##STR1## where A is an ethyl or propyl group which is mono-substituted by defined substituents or a di(loweralkyl)amino (loweralkoxy) carbonyl group and R is a phenyl group which may be substituted by defined substituents.