Peptide sweeteners. 5. Side-chain homologues relating zwitterionic and trifluoroacetylated amino acid anilide and dipeptide sweeteners.

Side-chain homologues of sweet trifluoroacetyl-alpha-L-aspartyl-p-cyanoanilide have been synthesized and tasted. Removal of the trifluoroacetyl group only changes the potency of sweet taste, not the taste property. These results have been compared with the structure-taste relationships of dipeptide sweeteners. An informative discontinuity of taste effects was found to exist with novel aminomalonyl dipeptide derivatives. The results are explained on topochemical grounds.