The stereoisomer D-phenylalanine (DPA) may be produced by conventional organic and natural synthesis, either as a single enantiomer or being a part of the racemic combination. It does not get involved in protein biosynthesis although it is found in proteins in modest amounts - particularly aged proteins and foodstuff proteins https://revivalschem.com/product/buy-tropacocaine-hcl-online-near-me/