There is provided an antidiabetic enolic glucoside of phenylpyruvic acid and derivatives thereof for use as medicaments, especially normoglycemic agents, i.e. for lowering blood glucose levels to normal levels in mammals that are obese, pre-diabetic or have diabetes, obesity and/or syndrome X. Hence the compounds of the present invention help to manage blood sugar levels, i.e. helping the body by balancing the blood sugar levels; helping to keep balanced blood glucose levels, particularly in humans with diabetes; aiding by enhancing the glucose uptake by the cells and by reducing sugar levels, thus improving or restoring the glucose tolerance; optimizing the glycemic response; normalizing the glucose tolerance.