InChI=1/C6H12O4/c1-3-10-6(9)5(8)4(2)7/h4-5,7-8H,3H2,1-2H3/t4-,5-/m1/s butanoic acid, 2,3-dihydroxy-, ethyl ester, (2R,3R)- ethyl (2R,3R)-2,3-dihydroxybutanoate