1,4-dimethyl-1H-pyrazole-5-carboxylic acid 1H-pyrazole-5-carboxylic acid, 1,4-dimethyl- InChI=1/C6H8N2O2/c1-4-3-7-8(2)5(4)6(9)10/h3H,1-2H3,(H,9,10