Benzoyl glucuronide

Quick26 re-investigated the effect of alkali and hydrocyanic acid on benzoyl glucuronide and found that in 21 hours only 8.9% of the benzoic acid was liberated, while only 3.9% of the original reducing power of the glucuronide remained. 

Disposition in the Body. Readily absorbed after oral administration. It is conjugated with aminoacetic acid to form p-aminohippuric acid which is excreted in the urine together with a small amount of / -aminobenzoyl glucuronide, / -acetamido-benzoyl glucuronide, and traces of / -acetamidohippuric acid, p-acetamidobenzoic acid, and unchanged aminobenzoic acid. Aminobenzoic acid may be detected in the urine as a metabolite of amethocaine, benzocaine, and procaine. 

Benzoic acid 122 50 1.2 Mainly hippuric acid and benzoyl glucuronide... 

A typical glucuronide of type I is benzoyl /3-D-glucuronide (R = CaH5-) and of type II phenyl /3-D-glucuronide (R = C6H5-), which are, respectively, metabolites of benzoic acid and phenol in most species. Glucuronides of types I and II are often designated ester and ether ... 

The NBT-PABA test of pancreatic function is based on the hydrolysis, by chymotrypsin, of a synthetic tripeptide— N-benzoyl-l-tyrosyl-p-aminobenzoic acid. The tripeptide, variously called NBT-PABA, BTP, or bentiromide, is administered orally together with a test meal to stimulate pancreatic secretion. BTP is specifically hydrolyzed by chymotrypsin in the duodenum to release PABA, which is subsequently absorbed in the intestinal tract and metabolized in the liver to hippurate and to PABA glucuronide and PABA acetylate. These arylamines are then excreted by the Iddney. In the presence of low chymotrypsin, as found in pancreatic insufficiency, less peptide is hydrolyzed, and therefore less chromogen is excreted in the urine or found in serum. Thus the amount of PABA detected in serum or urine is an indirect measure of chymotrypsin activity in duodenal content. 

Ketoprofen is rapidly and nearly completely absorbed on oral administration, reaching peak plasma levels within 0.5 to 2 hours. It is highly plasma protein bound (99%) despite a lower acidity (pKa = 5.9) than some other NSAIDs. Wide variation in plasma half-lives has been reported. It is metabolized by glucuronidation of the carboxylic acid, CYP3A4 and CYP2C9 hydroxylation of the benzoyl ring, and reduction of the keto function. 

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