5.2.1.10 trans-2-Chloro-4-carboxymethylenebut-2-en-1,4-olide - 979 5.2.1.10 trans-2-Chloro-4-carboxymethylenebut-2-en-1,4-olide enzyme in pathway of 3,5-dichlorocatechol catabolism 369256