Peptide sweeteners. 7. Taste relationships of trifluoroacetyl-L-aspartylanilides

A series of analogues of trifluoroacetyl-alpha-L-aspartylanilides substituted at various positions on the aromatic ring was synthesized and tasted. The position of the substitution is essential for the nature of the taste response. The results clearly establish the close relationship between sweet and bitter taste for these compounds. Combined electronic and topochemical contributions are discussed.