3-4 Hydroxyphenoxy benzoic acid

Hutson and Logan (1986) reported on the metaboUc fate in rats of WL85871, which was a mixture of two isomers of cypermethrin [(IR, cis) aS and (IS, cis) oR]. Approximately 20% of the ingested compound was not absorbed and was eliminated unchanged in the feces. There was no evidence for any racemization of the chiral centers of WL85871 either in the intestine, the feces, or in fat. Approximately 40% of a 2.0 mg/kg dose was eliminated in urine as 3-(4-hydroxyphenoxy) benzoic acid sulfate (CAS no. 58218-91-0). Some hydroxylation occurred before hydrolysis. The small proportion of the dose stored in adipose tissue was eliminated by biphasic kinetics (2-3 days and 17-26 days). 

Humans eliminated conjugates of 3-phenoxybenzoic acid (CAS no. 3739-38-6), 3-(4 -hydroxyphenoxy) benzoic acid (CAS no. 35065-12-4), and cyclopropane-carboxylic acid (DCCA CAS no. 55701-05-8) in urine according to Woollen et al. (1992). In the Woollen et al. study, cypermethrin was administered orally to six male volunteers as a single dose (3.3 mg cis trans 1 1) and dermally to six volunteers at a dose of 31 mg/800 cm (cis trans 56 44) of skin. Cypermethrin was orally absorbed between 27 and 57% (mean of 36%) based on the elimination of DCCA and four times greater based on the recovery of benzoic acid conjugates. In the case of the dermal studies, 1.2% of the appUed dose was recovered in urine as benzoic acid conjugates. 

The degradation pathways of cypermethrin, deltamethrin and fenpropathrin have been smdied. The fenpropathrin metabolism pathway of Achromobacter sp. (Fig. 3.21a) was proposed by Wang et al., it was suggested that fenpropathrin was hydrolyzed to 2,2,3,3-tetramethylcyclopropanecarboxylic add and 3-phenoxybenzaldehyde, which was later converted to 3-phenoxybenzoic acid. The phenoxybenzoic acid was transformed to 3-(4-hydroxyphenoxy)benzoic acid, which was oxidized to 3,4-dihydroxybenzoic acid (protocatechuate) and p-hydroquinone. The protocatechuate was further oxidized through an ortfe>-cleavage pathway, and p-hydroquinone was degraded via the metabolite benzene-1,2,4-triol (Wang etal. 2011). 

On the other hand, the transformation of 3-phenoxybenzoic acid to 3-(4-hydroxyphenoxy)benzoic acid was not detected in the degradation pathway of Sphingobium sp. JZ-2 smdied by Guo et al., where 3-phenoxybenzoic acid spht directly into protocatechuate and phenol (Guo et al. 2(X)9). Similarly, the... 

The oxidative coupling of 2-(4-hydroxyphenoxy)benzoic acid to the spiran (525) is brought about by lead(IV) oxide (61JCS2312). The spiran is converted into 2,3-diacetoxyxanthone on reaction with boron trifluoride in acetic anhydride. 

Diiodo-4-(3-iodo-4-hydroxyphenoxy)benzoic acid Acetic anhydride... 

To 3 parts of 3,5-diiodo-4-(3-iodo-4-hydroxyphenoxy)benzoic acid 10 parts of acetic acid anhydride was added and mixture was heated on oil bath for some hours. In the result of this reaction amorphous precipitate was obtained. After recrystallization from glacial acetic acid 2.4 parts of 3,5-diiodo-4-(3-iodo-4-acetoxyphenoxy)benzoic acid were obtained. 

According to Kaneko (2010), the major metabohc reaction is ester hydrolysis followed by hydroxylation of the alcohol moiety and its subsequent oxidation to an acid. The cyano group of the alcohol, benzeneacetonitrile, a-hydroxy-3-phenoxy (CAS no. 39515-47-4) is converted to an SCN ion. The major metabolites of the acid moiety are cyclopropylcarboxylic acid and its glucuronide, while the alcohol moiety is converted to PB acid (benzoic acid, 3-phenoxy) (CAS no. 3739-38-6), 4 -OH PB acid (benzoic acid, 3-(4-hydroxyphenoxy)) (CAS no. 35065-12-4), and the sulfate of 4 -OH-PB acid (benzoic acid, 3-[4-(sulfooxy)phenoxy]) (CAS no. 58218-91-0). 

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