(+/-)-2-hydroxy-4-oxopentanedioic acid 1187-99-1 2-Oxo-4-hydroxyglutarate 2-k-4-OH-glutarate 2-keto-4-hydroxyglutarate 4-hydroxy-2-ketoglutarate 4-hydroxy-2-oxoglutarate D-4-HYDROXY-2-KETO-GLUTARATE D-4-hydroxy-2-ketoglutarate