3-Pyrroline-3-carboxylic acid, 4-hydroxy-1-methyl-5-oxo-, ethyl ester 4450-97-9 Ethyl N-methyl-4-hydroxy-5-oxo-3-pyrroline-3-carboxylate iron chelate Iron chelate, N-methyl-4-hydroxy-5-oxo-3-pyrroline-3-carboxylic acid ethyl ester Opc iron chelate