HYDANTOINS MODIFIED WITH CARBOXYLIC ACID ESTER GROUPS

This invention relates to a process for the preparation of a compound of general formula (I) in which R represents an alkyl groups Rl and R2 represent hydrogen or an alkyl group; R3 represents hydrogens an alkyl or cycloalkyl group which is unsubstituted or substituted with halogen, hydroxyl or alkoxy; an aryl group which is unsubstituted or substituted with nitro, halogen, alkyl, alkoxy, haloalkyl or hydroxyl; an aralkyl group or a heterocyclic group derived from furan, pyridine, thiophene, imidasole, pyrimidine or piperazine, R4 represents hydrogen; an alkyl or cycloalkyl group which are unsubstituted or substituted with halogen, hydroxyl or alkoxy; an aryl group which is unsubstituted or substituted with nitro, halogen, alkyl, alkoxy, haloalkyl and/or hydroxyl; an aralkyl group or a heterocyclic group as defined above, X represents oxygen or sulphur and n represents an integer from one to 30 by reaction with a urea with a corresponding 1,2-ethylene-dicar-boxylic acid ester which is either unsubstituted or alkyl substituted in a single stage reaction.