M-Hydroxyphenylacetic acids

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. 

Potassium tert-butoxide m-Hydroxyphenylacetic acids from hemiquinolesters... 

Rump [17] has described a cellulose thin layer method for the detection of phenolic acids such as m-hydroxybenzoic acid, m-hydroxyphenylacetic acid and wj-hydroxyphenylpropionic acid, in water samples suspected to... 

Hydroxyphenylacetic acid [614-75-5] M 152.2, m 148-149", b 240-243"/760mm, pKEst(i)-4.3, pKEst(2)-10.1. Crystd from ether or chloroform (m from latter is always lower). 

Metabolites of biogeiuc amines have also been analyzed by GC-ECD. For the simultaneous analysis of 5-hydroxyindole-3-acetic acid (5-HIAA), homovanillic acid (HVA) and m- and p-hydroxyphenylacetic acid (m-, p-HPAA), (metabolites of 5-HT, DA, and m- and p-tyramine acid respectively) in urine, a simple acidic extraction followed by derivatization with PFPA (derivatizes phenols) and hexafluoroisopropanol (deriva-tizes carboxylic acid groups) has been used (Davis et al., 1982 Baker et al., 1987). 

Aura, A.M., O Leary, K.A., Williamson, G., Ojala, M., Bailey, M., Puupponen-Pimia, R., Nuutila, A.M., Oksman-Caldentey, K.M., and Poutanen, K., Quercetin derivatives are deconju-gated and converted to hydroxyphenylacetic acids but not methylated by human fecal flora in vitro, J. Agric. Food Chem., 50, 1725, 2002. 

Aura, A.M. et al.. Quercetin derivatives are deconjugated and converted to hydroxyphenylacetic acids but not methylated by human fecal floral in vitro, J. Agric. Food Chem., 50, 1725, 2002. 

Fig. 3.1.7 Detection of HG by the GC-MS TIC method in the urine of patients with MCAD deficiency collected at different clinical statuses. A, left panel Organic acid profile of an acutely ill patient. The arrow indicates the portion of the chromatogram shown in the middle panel. Peak labeling 1 HG, 2 4-hydroxyphenylacetic acid. Right panel extracted ion chromatograms of the [M-15]+ ion of HG (m/z 230 red) and 4-hydroxyphenylacetic acid (m/z 281). Patient recovering from an acute episode. C Asymptomatic patient. The latter profile represents a situation where there is a high probability that HG may not be detected by a GC-MS TIC method...

Fluoro-4-hydroxyphenylacetic acid [458-09-3] M 170.1, m 33°. Crystd from water. 

Hydroxyphenylacetic acid [621-37-4] M 152.2, m 137°. Crystd from benzene/ligroin. 

Rump [17] has described a cellulose thin layer method for the detection of phenolic acids such as iw-hydroxybenzoic acid, iw-hydroxyphenylacetic acid and m-hydroxyphenylpropionic acid, in water samples suspected to be contaminated with liquid manure. The phenolic acid is extracted with ethyl acetate from a volume of acidified sample equalling lmg of oxygen consumed (measured with potassium permanganate). The ethyl acetate is evaporated and the residue dissolved in ethanol. After spotting of a lpm aliquot on a cellulose plate the chromatogram is developed by capillary ascent with the solvent n-propanol-w-butanol-25% NH3-water (4 4 1 1 by vol). The solvent front is allowed to advance 10cm. The air-dried plate is sprayed with a diazotised p-nitroanilinc reagent to make the phenolic acids visible. 

Synthesis of fluorine-18 labelled fluoro-m-tyrosine, fluoro-m-tyramine and fluoro-3-hydroxyphenylacetic acid... 

HYDROXY-2-PHENOXYETHANE see PEROOO N-(4-HYDROXYPHENYL)ACETAMIDE see HIMOOO m-HAT)ROXYPHENYL ACETATE see RDZ900 a-HYDROXYPHENYLACETIC ACID see MAPOOO HYDROXYTHENYLACETONITRILE see MAP250... 

Oxidative degradation of substituted pyruvic acids is accomplished by treating an aqueous solution of the sodium salt with 30% hydrogen peroxide (Superoxol) at 0-15°. Good descriptions have been published for the preparations of o-hydroxyphenylacetic acid (34%), 3,4-dim.ethoxy-phenylacetic acid (60%), m-chlorophenylacetic acid (57%), and o-nitro-phenylacetic acid. ... 

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