SYNTHESIS AND REACTIONS OF SOME 2-HYDROXYALKYL ESTERS OF SUBSTITUTED PIPERAZINE-4-CARBOXYLIC ACIDS

This project was undertaken to gain a better under-standing of the synthesis and reactions of some 2-hydrox-alkyl esters of various substituted piperazine-4-carboxylic acids. The reactions were of four types but each involved piperazine or a monosubstituted piperazine, and a cyclic carbonate, The first of these reactions utilized a piper azinyl compound and either ethylene or propylene carbonate in the production of an hydroxyaIkyl eater of the piperazine-4-carboxylic acid. The second portion of the work involved the reaction of the hydroxy group of this ester with a chlorinating agent producing the related 2.dhloroalkyl ester. Subsequently the chloro group was reacted with a primary or a secondary amine to give the corresponding 2-aminoalkyl ester. The formation of derivatives of the 2-hydroxyalkyl esters was the third area of research. The alcoholic comp-ounds produced in the first syntheses were reacted with isocyanates and with various benzoyl chlorides producing the corresponding urethanes and benzoates. The final undertaking was the attempted preparation of hydroxyalkyl substituted piperazines using piperazine and ethylene or propylene carbonate. Although no new compounds resulted, one method did appear to be of value as a starting point for further study. Those new compounds resulting from this project will be submitted for pharmacologic evaluation as it is hoped that at least a few may prove to be of value in some area of thera-peutics