title: Peptide sweeteners. 3. Effect of modifying the peptide bond on the sweet taste of L-aspartyl-L-phenylalanine methyl ester and its analogues.
abstract: A series of analogues designed to assess the importance of the amide bond in the dipeptide sweetener L-aspartyl-L-phenylalanine methyl ester has been synthesized and tested. The peptide bond was methylated, replaced by an ester bond, or reversed. all of these modifications produced compounds that did not have a sweet taste. We conclude that the steric, electronic, and directional characteristics of the amide bond are essential for biological activity in the dipeptide sweeteners.
mesh_terms: D001218:Aspartame / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000494:pharmacology; D004151:Dipeptides / Q000031:analogs & derivatives*; D006801:Humans; D007477:Ions; D008968:Molecular Conformation; D013329:Structure-Activity Relationship; D013549:Sweetening Agents / Q000138:chemical synthesis / Q000494:pharmacology*
chemical_list: D004151:Dipeptides; D007477:Ions; D013549:Sweetening Agents; D001218:Aspartame