label: 2-(1-hydroxyethyl)thiamine diphosphate + 2-oxobutanoate = (S)-2-ethyl-2-hydroxy-3-oxobutanoate + thiamine diphosphate
label_lc: 2-(1-hydroxyethyl)thiamine diphosphate + 2-oxobutanoate = (s)-2-ethyl-2-hydroxy-3-oxobutanoate + thiamine diphosphate