2-furancarboxylic acid, tetrahydro-5-oxo- 4344-84-7 5-Oxo-tetrahydro-furan-2-carboxylic acid 5-Oxotetrahydrofuran-2-carboxylic acid InChI=1/C5H6O4/c6-4-2-1-3(9-4)5(7)8/h3H,1-2H2,(H,7,8