reaction mixture for 24 to 48 hours the 2 4 dicyanoglutarimide product v is obtained and is hydrolyzed in strong mineral acid to the dicarboxylic acid product iv dehydration with acetic anhydride yields the dialkylglutaric acid anhydride iia which in turn can be converted to the dialkylglutarimide iib by treating with ammonium hydroxide under dehydrating conditions the n substituted glutarimide iic is readily obtained by treating iib with an appropriate 1 4 disubstituted butane e g 1 4 dibromobutane the piperazine intermediates iii are described in the aforementioned wu et al patents and certain references cited therein although these procedures are applicable to the preparation of other piperazine intermediates not specifically disclosed therein but which are required as intermediates for the present invention a representative synthesis of iiic is given as a working example for further exemplification intermediates iiia and iiib are readily obtainable from iiic using the standard methods shown by wu et al str16 this synthetic scheme begins with a commercially available z substituted uracil and proceeds by known reactions to the desired piperazine intermediate although the route via carbethoxypiperazine is more involved the higher yield of iiic without by products makes it preferred the formula i compounds are useful psychotropic agents which exhibit selective anxiolytic action in particular these improved compounds appear to offer an advantage over buspirone and its close analogs in that antipsychotic or neuroleptic action with its potential adverse side effects appears markedly reduced or absent this realizes one objective of the instant invention i e to increase selectively for this class of anxiolytic agents various in vivo and in.