Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:P00790 (PGA)
 2,475 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

1. A number of folates labelles with 14-C were administered orally to rats, at various doses, and urinary, faecal and hepatic folates examined. 2. 10-Formylpteroylmonoglutamic acid ( 10CHO--PGA) entered the folate pool very slowly, and is thought to be relatively ineffective in nutrition. 3. 10-Formyl[2-14-C]tetrahydrofolic acid (10CHO--[2-14-C]THF) entered the folate pool very rapidly. 5-Methyl[2-14-C]tetrahydrofolate (5CH3--[2-14-C]THF) was the major urinary folate. 4. 5-Formyl[2-14-C]tetrahydrofolic acid (5CHO--[2-14-C]THF) entered the folate pool only to a small extent. 5CHO--[2-14-C]THF, given intravenously, produced no urinary 5CH3--[2-14-C]THF in the first 6 h. 5. 5,10-Methylidyne[2-14-C]tetrahydrofolic acid was metabolized to an extent which was dependant on the dose. At doses of 3 and 30 mug/kg body-weight, 5CH3--[2-14-C]THF represented 5-4 and 20% respectively of urinary folates anf for 10CHO--[2-14]PGA, the values were 16% of total urinary folates after the higher dose, and 78-5% after the lower dose. 6. Results obtained for the metabolism of 5CH3--THF varied depending on the position of the labelling: 5-14-CH3-THF gave no labelled urinary folate, the methyl group being lost rapidly. When 5CH3--[2-14-C]THF was given, it appeared as the major urinary folate. 7. Folates found in the liver after oral administration of labelled folates were identified by thin-layer chromatography; only folate monoglutamates were identified.
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PMID:The metabolism of some folates in the rat. 107 38

To construct a new strategy for synthesis of cyclopentanoids, the transition metal-catalyzed coupling reaction of cis 4-cyclopentene-1,3-diol monoacetate 1 with hard nucleophiles, R(T)-m, was investigated (eq 1 in Chart 1). Although preliminary experiments using PhZnCl, PhSnMe(3), [Ph-B(Me)(OCH(Me)CH(Me)O)]-Li(+) (6a) (derived from boronate ester 4a (R(T) = Ph) and MeLi) in the presence of a palladium or a nickel catalyst resulted in production of unidentified compounds, enone 16, and/or ketone 17 or recovery of 1, a new borate 5a (derived from 4a and n-BuLi) in the presence of a nickel catalyst (NiCl(2)(PPh(3))(2)) in THF at room temperature furnished the trans coupling products 2a (R(T) = Ph) and 3a (R(T) = Ph) in high combined yield, but with a low product ratio of 0.9:1. The ratio was improved to 13:1 by addition of t-BuCN and NaI into the reaction mixture. This is the first successful example of the reaction of 1 with a hard nucleophile, and the increase in the ratio, realized with the additives, is unprecedented. This reagent system (borate 5 (1.2-1.8 equiv), NiCl(2)(PPh(3))(2) (5-10 mol %), t-BuCN (2-5 equiv), NaI (0.5-1 equiv), THF, room temp) was further investigated with aryl borates 5b-g and alkenyl borates 5h-n to afford 2b-n in moderate to good yields (52-89%) with practically acceptable levels of the regioselectivity (5 approximately 21:1), thus establishing the generality of the reaction (Table 2, eqs 6 and 7). Starting with the products of the coupling reaction, syntheses of the prostaglandin intermediates 13 and 14 (for 11-deoxy-PGE(2) and PGA(2)) and Delta(7)-PGA(1) methyl ester (15) were accomplished efficiently. During these investigations, LDA, LiCA, and LHMDS were found to be equally efficient bases for aldol reaction at the alpha' (alpha prime) position of cyclopentenones 39, 40, and 41 (Table 3).
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PMID:A new method for installation of aryl and alkenyl groups onto a cyclopentene ring and synthesis of prostaglandins. 1235 6

A new type of double hydrophilic block copolymer, poly(ethylene oxide) (PEO)-block-poly(glycerol monoacrylate) (PGA) have been synthesized via atom transfer radical polymerization of solketal acrylate (SA) using PEO-Br as macro-initiator, and subsequent hydrolysis of the acetal-protecting group in 1N HCl solution in THF. The polymerization is of a "living" nature and the copolymers with controlled molecular weight and narrow polydispersity (M(w)/M(n) = 1.01-1.03) were obtained. The complete hydrolysis of the acetal-protecting group was verified by IR and NMR spectroscopies. A hydrophobic fluorescent compound, 1-pyrenecarboxaldehyde, was used as a model drug, which was covalently bound to the PEO-b-PGA block copolymer via a pH-sensitive acetal linkage. The kinetics of the pyrene release was studied in THF/aqueous buffers at pH 5.0 (close to pH in endosomes) and 7.4 (pH of blood plasma) by fluorescent spectroscopy. The pyrene was released much faster at pH 5.0 than that at pH 7.4. The micelle behavior in solutions at pH 5.0 and 7.4 was studied by dynamic light scattering. All results show that this double hydrophilic PEO-b-PGA is a promising candidate for potential application as drug carrier for those carbonyl-containing hydrophobic drugs.
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PMID:Double hydrophilic block copolymers PEO-b-PGA: synthesis, application as potential drug carrier and drug release via pH-sensitive linkage. 1797 19

The purpose of this research was to determine mandelic, phenylglyoxylic, hippuric, o-, m- and p-methylhippuric acids, the six urinary metabolites of styrene, toluene and xylene by high performance liquid chromatography (HPLC). These metabolites were extracted in an acid medium, transferred into a basic solution and back extracted again using ethyl acetate, and the organic phase was evaporated to dryness under a compressed air flow at room temperature. The residue obtained was dissolved in 1 ml mobile phase solution of 0.01 M potassium orthophosphate in 0.3% acetic acid (adjusted to a pH of 2.5 with orthophosphoric acid):tetrahydrofuran:acetonitrile(87:5:8) and 100 microl was injected into a HPLC equipped with a 4.6 x 250 mm ODS3-C18 reversed phased column and ultraviolet (UV) detector at a wavelength of 254 nm. All metabolites were clearly separated within 21 minutes. The detection limits of the method were 1.1 ng/ml for PGA, 4.9 ng/ml for HA, 17.0 ng/ml for MA, 2.5 ng/ml for o-MHA, 1.7 ng/ml for p-MHA and 2.0 ng/ml for m-MHA. The percent recoveries of the six metabolites were 99.2-101.8% with percent coefficients of variation of less than 2%. The method was applied to the analysis of urine samples of twelve workers exposed to toluene, xylene and styrene in a paint factory. The 5-day post-shift urinary excretions of the six metabolites in these workers are presented. The metabolites were found at levels greater than the Biological Exposure Index (BEI) recommended by the American Conference of Governmental Industrial Hygienists (ACGIH).
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PMID:High performance liquid chromatography for determination of urinary metabolites of toluene, xylene and styrene and its application. 1906 9