2H-Pyran-5-carboxylic acid, 3-benzyl-4-hydroxy-6-methyl-2-oxo- 3-Benzyl-4-hydroxy-5-carboxy-6-methyl-alpha-pyron [German] 3-Benzyl-4-hydroxy-6-methyl-2-oxo-2H-pyran-5-carboxylic acid UP6930000