(2E)-2-(1-hydroxyethyl)but-2-enoic acid 2-butenoic acid, 2-(1-hydroxyethyl)-, (2E)- InChI=1/C6H10O3/c1-3-5(4(2)7)6(8)9/h3-4,7H,1-2H3,(H,8,9)/b5-3