2- Hydroxyhippuric acid

Ginkgo extract has no effect on the hepatic microsomal drug oxidation system, as measured by antipyrine elimination, even at doses of 400 mg per day (Duche et al. 1989). Ginkgo metabolites, the substituted benzoic acids (4-hydroxybenzoic acid conjugate, 4-hydroxyhippuric acid, 3-methoxy-4-hydroxyhippuric acid, 3,4-dihydroxybenzoic acid, 4-hydroxybenzoic acid, hippuric acid and 3-methoxy-4-hydroxybenzoic acid [vanillic acid]), are excreted in urine (Pietta et al. 1997). 

Hydroxybenzoic acid 2-Hydroxyhippuric acid 4-Hydroxybenzoic acid 2,5-Dihydroxyphenylacetic acid 2-Hydroxyphenylacetic acid ... 

Vermeersch and co-workers have reported the case of a 4-month-old girl who presented with agitation, hyperexcitation, fever, dehydration, polypnea and metabolic acidosis. H NMR spectroscopy of the lyophilized urine from the patient showed the presence of 2-hydroxybenzoic acid (salicylic acid), o-hydroxyhippuric acid and 2,5-dihydroxyhippuric acid, which indicated that she had been poisoned with salicylate (aspirin). It is notable that this study was completed at 80 MHz, a relatively low field strength. 

Recently Gallice et al. used high-performance liquid chromatography (HPLC) and nuclear magnetic resonance spectroscopy (NMR) to identify a double conjugate of glucuronidate-o-hydroxyhippuric acid in ultrafiltrates of uremic plasma (G6). This compound had been previously described by Zimmerman et al. as a fraction of the so-called uremic middle molecules (Z7, Z8). So far no data have been reported on the toxicity of this compound. 

The last of these, as well as m-hydroxyhippuric acid, is found in almost all urine samples, whereas the presence of m-hydroxybenzoic and m-hydroxyphenylacetic acids is frequent that of m-hydroxyphenylpro-pionic acid is much less so. 

The normal daily excretion of m-hydroxyhippuric acid by man ranges from 2 to 150 mg, most subjects eliminating 4-6 mg (A15). The excretion of m-hydroxyphenylhydracrylic acid ranges from 2 to 150 mg (All), whereas the values found for m-hydroxybenzoic acid are, respectively, 8.8 mg in human males and 15.0 mg in females (B31), or 10-16 mg (T22). 

Simultaneous diazepam, diphenhydramine, o-hydroxyhippuric acid, MPPH, niacin, toluene... 

AMINO ACIDS L-Proline. Ruthenium tetroxide. a-AMINO ALDEHYDES Diisobutylaluminum hydride. a-AMlNO ALCOHOLS Rhodium on alumina. a-AMINO-7-KETO ACIDS a-Hydroxyhippuric acid. 

Synonyms 0-Hydroxyhippuric acid 0-hydroxy-N-benzoylglycine Trade names ... 

H2S04 added at 0 to a stirred ice-cooled suspension of a-hydroxyhippuric acid and methyl mercaptan in glacial acetic acid, and stirred 2 days at room temp. -methylthiohippuric acid. Y 84%. F. e., also analogous esters by a related process, s. U. Zoller and D. Ben-Ishai, Tetrahedron 31, 863 (1975). 

Hydroxyhippuric acid allowed to react at room temp, with benzene in coned. H2SO4 N-benzoylphenylglycine. Y 91%. F. e. s. D. Ben-Ishai, I. Satati, and Z. Berler, Chem. Commun. 1975, 349 Tetrahedron 32, 1571 (1976) a-acylamino-carboxylic acids from active methylene compds. s. Chem. Commun. 1975, 905. 

Ginkgolic acid is a mixture of several 2-hydroxy-6-alkyIbenzoic acids, two of which (alkyl = 1-octene or 3-decene) were baseline resolved on a 45 C Cjg column (A = 308nm) with a 92/7/1 acetonitrile/water/acetic acid mobile phase [1053]. Elution was complete in 6 min and peaks of interest were well resolved from all extracted material. In a separate study, Pietta et al. [1054] isolated six metabolites (hippuric acid, 4-hydroxy- and 3-methoxy-4-hydroxyhippuric acid, 4-hydroxy-, 3,4-dihydroxy-, and 3-methoxy-4-hydroxybenzoic acid) of Ginkgo biloba leaf extracts from urine and blood samples and analyzed on a Cjg column (photodiode array detector). An 88/5/5/2 water/acetonitrile/methanol/acetic acid mobile phase generated good resolution and complete elution in 15 min. The standard used was at the 1 mg/mL level. 

Hydroxyhippuric Acid Salicyloylamino-aeetic acid, o-hydroxybentoylglycine, salicyloyl-glycine)... 

Hydroxyhippuric Acid ( -Hydroxy-bem lamtnoacetic add, m - hydroxybenxoyl -glycine). 

Hydroxyhippuric Acid (4 Hydroxy -benzotfiaminoaeetic actd,p-hydroxybemoylglydne). 

Some parts are metabolised through enzymes to p-hydroxyhippuric acid, which is excreted in the urine as well. Additionally relatively small quantities of parabens are linked to esters of glucuronic acid and excreted in the urine by this route. Only small concentrations of p-hydroxybenzoic acid are detectable in the blood. 

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