N-terminal L-phenylalanyl-L-alpha-amino acid(1+) residue
n-terminal l-phenylalanyl-l-alpha-amino acid(1+) residue
An α-amino-acid cation residue derived from N-terminal <small>L</small>-phenylalanyl-<small>L</small>-α-amino acid residue; major species at pH 7.3.