Synthesis of N,N2-Disubstituted DL-β-Asparagines as Potential Hypocholesteremics

By the addition of equivalent amount of appropriate amine on the carbon-carbon double bond of N-substituted maleamic acids under the influence of pyridine, a number of potential hypocholesteremics, N,N²-disubstituted DL-β-asparagines was prepared. For all N-alkyl- and N-arylmaleamic acids, the addition proceeded smoothly and resulted in satisfactory yields, but in the cases of N-heterocyclic analogs, transamidation was observed to occur simultaneously with the addition reactions.