The Structure-taste Relationships of Aspartyl Dipeptide Esters

Abstract

The molecular features common to sweet-tasting dipeptide esters are described. The molecular features of sweet amino acids were represented by the Fischer projection formulas and sweet peptides were related to the sweet amino acids through the Fischer projection formulas of the peptides. It was concluded that a peptide is sweet when it takes the formula 5a, whereas when it takes the formula 5 b it is not sweet. It was also concluded that a third binding site (R₁ in 5 a) besides the postulated AH-B system in a sweet molecule is necessary for an intense sweetness potency. The location of the site in the molecule relative to the AH-B system is important, as well as the shape and size of this site, because the third binding site is considered to participate in hydrophobic interaction with a similar binding site on the taste receptor. Increased sweetness is observed when these requirements are satisfied.