2,4-D and Related Compounds 
2- and 4-Chlorophenoxyacetic Acid (2-CPA and 4-CPA) 
Both compounds were degraded by arthrobacter sp. to their respective 
phenols. Some chloride was also released (894). 
4-Chlorophenol (Il) was metabolized to 4-chlorocatechol (II) and a- 
carboxymethylene-A -butenolide (III) (1679, 1691, 1692). 
0 
Pe OH OH 
CHSC 00n 
ou -OH COOH 
——>> — > ——p~ || ey 
f 1 i Cl 
(1) (II) COOH 
Cal 
0 
<4 
(III) 
4-(2-CPB) [4-(2-Chlorophenoxy) butyric Acid] (I) 
4-(3-CPB) [4-(3-Chlorophenoxy) butyric Acid] (ITI) 
4-(4-CPB) {4-(4-Chlorophenoxy) butyric Acid] (III) 
Using aspergillus niger: 
Metabolism of I gave rise to 4-(2-chlorophenoxy)-3-hydroxybutyric acid, 
4-(2-chloro-4-hydroxyphenoxy) butyric acid, 2-chlorophenoxyacetic acid, 2- 
chloro-4<hydroxyphenoxyacetic acid and 2-chloro~3-hydroxyphenoxyacetic 
acid (441), 
Metabolism of II produced 4-(3-chlorophenoxy)-3-hydroxybutyric acid, 
3-chlorophenoxyacetic acid and 3-chloro-6-hydroxyphenoxyacetic acid (441). 
Metabolism of III produced 4-(4-chlorophenoxybutyric acid, 4- 
chlorophenoxyacetic acid, 4-chloro-2-hydroxyphenoxyacetic acid, 4-chloro- 
3-hydroxyphenoxyacetic acid (441). 
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