5,5'-Dioxo-1,1'-methandiyl-bis-L-prolin, 1,1'-Methylenebis(5-L-oxoproline), 5,5'-dioxo-1,1'-methanediyl-bis-L-proline, 1,1'-methanediylbis(5-oxopyrrolidine-2-carboxylic acid)(non-preferred name), acide L methylene bis N-(oxo-5 pyrrolidine carboxylique-2), L-(+)-1,1'-methylenebis[5-oxo-2-pyrrolidinecarboxylic acid]