Determination of natural corticosteroids in urine samples from sportsmen

Rivero-Marabé, J.J; Maynar-Mariño, J.I; Garcı́a-de-Tiedra, M.P; Galán-Martı́n, A.M; Caballero-Loscos, M.J.; Mariño, Marcos Maynar

doi:10.1016/s0378-4347(01)00306-1

Cited by 27 publications

(26 citation statements)

References 6 publications

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“…Of various methods for the reductive allomerization at C-5 of D 4 -3-ketosteroids reported previously, 24,25,29,30) it seemed to us that the most feasible route, starting from the readily available 1b through the inversion of the configuration at C-5, offered a better way to obtain the 3-ethoxy-3,5-diene intermediate (17). 24,25) The procedures employed were (1) the etherification of 1b with triethyl orthoformate in the presence of a catalytic amount of p-toluenesulfonic acid and (2) selective reduction of the D 3,5 -bond in the resulting 17 over 10% Pd/C catalyst, yielding enol ether (18), which after treatment with HCl gave the desired 19a. After chromatographic purification, the allomerized 3-oxo-5a compound (19a) was isolated in a fairly good yield.…”

Section: Resultsmentioning

confidence: 99%

“…To the crude 27b dissolved in a small amount of methanol was added 10% HCl (0.5 ml), and the mixture was left standing at room temperature for 30 min. The resulting solution was loaded onto a Sep-Pack ® tC 18 cartridge. Elution with methanol-water (3 : 7, v/v) gave a homogenous fraction which was then adjusted to pH 8 with 10% methanolic NaOH.…”

Section: -Acetoxy-3amentioning

confidence: 99%

“…Elution with methanol-water (3 : 7, v/v) gave a homogenous fraction which was then adjusted to pH 8 with 10% methanolic NaOH. The resulting solution was passed through a Sep-Pak ® tC 18 cartridge and washed with 5% aqueous methanol. Elution with 25% methanol gave 27c which recrystallized from methanol-EtOAc as colorless amorphous substances: yield, 33 mg (28%); mp 141-144°C.…”

Section: -Acetoxy-3amentioning

confidence: 99%

“…3a a,17a a,21-Trihydroxy-5a a-pregnan-20-one (Allo-THS; 27d) The compound 27a (285 mg), treated with 10% HCl (50 ml) at room temperature for 30 min and processed as described for the preparation of 20d, yielded the desilylation product. The crude residue was dissolved in water was loaded onto a Sep-Pak ® tC 18 cartridge and elution with 80% methanol afforded 27d which recrystallized from methanol as colorless amorphous substances: yield, 215 mg (ca. 100%); mp 188-189°C (lit., mp 225-226°C 24) ; mp 203-213°C 36) ).…”

Section: -Acetoxy-3amentioning

confidence: 99%

“…[14][15][16][17][18] Although these methods are robust and sensitive, sample preparation in these indirect methods is time consuming, and the GC-MS sample throughput is relatively low. Thus the development or more straightforward methods based on the direct analysis of steroid conjugates without the need for a deconjugation process is of great interest.…”

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confidence: 99%

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Potential Corticoid Metabolites: Chemical Synthesis of 3- and 21-Monosulfates and Their Double-Conjugates of Tetrahydrocorticosteroids in the 5.ALPHA.- and 5.BETA.-Series

Okihara

Mitamura

Hasegawa

et al. 2010

CHEMICAL & PHARMACEUTICAL BULLETIN

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As the principal glucocorticoid in humans, cortisol plays a crucial role in modulating the metabolic and homeostatic process that protects against stress, shock, inflammation, etc.3-7) It is synthesized primarily in the zona fasciculata with a small contribution from the zona reticularis.3) While cortisol is essentially secreted by the adrenal glands, cortisone is mainly produced using 11b-hydroxysteroid dehydrogenase isoenzymes, which interconvert cortisol to hormonally inactive cortisone.3) Cortisol and cortisone are extensively metabolized to tetrahydro-reduced derivatives: tetrahydrocortisol (THF) and tetrahydrocortisone (THE), and their 5a-stereoisomer (allo-THF and allo-THE, respectively). 3,[7][8][9] Metabolism decreases the biological activity of hormones and increases their water solubility by converting them to hydrophilic compounds that can be excreted in urine. Unmetabolized cortisol and cortisone comprise only ca. 0.1% of the total urinary cortisol metabolites. At least 90% of the tetrahydro-derivatives of cortisol and cortisone metabolites are excreted into the urine as sulfate or glucuronide conjugates.10-13) Tetrahydro-11-deoxycortisol (THS) and its 5a-stereoisomer (allo-THS) which are tetrahydro-reduced metabolites of 11-deoxycortisol (11-DOC), a biosynthetic precursor of cortisol, are also excreted in urine as conjugated forms. 8,10,12) In order to obtain information regarding the related biochemistry, physiology, and pathophysiology of endocrine disorders, it is necessary to identify all the corticosteroid metabolites found in urine, and determine the exact structure of their conjugates, their concentration, and the dynamics of their formation and disposal.At present, analytical methods for the detection of conjugated tetrahydrocorticosteroids are based on gas chromatography and mass spectrometric determination of hydrolyzed and derivatized compounds.14-18) Although these methods are robust and sensitive, sample preparation in these indirect methods is time consuming, and the GC-MS sample throughput is relatively low. Thus the development or more straightforward methods based on the direct analysis of steroid conjugates without the need for a deconjugation process is of great interest. The application of liquid chromatographic separation interfaced by soft ionization techniques, such as electrospray ionization (ESI) with tandem mass spectrometry and/or ion trap mass spectrometry, offers an effective analytical tool for the direct monitoring of the urinary conjugates of tetrahydrocorticosteroids. 19,20) Recently, we reported a highly sensitive and specific liquid chromatography/ESI-linear ion trap mass spectrometry method for the direct measurement of the glucuronide conjugates of THF, THE, THS, and their 5a-stereoisomer in human urine.21) The authentic glucuronides had been chemically synthesized by Hosoda et al. [22][23][24][25] One significant drawback of sulfate conjugate analysis, however, is still the lack of reference materials, which are essential for the development and application of ...

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Section: Resultsmentioning

confidence: 99%

Section: -Acetoxy-3amentioning

confidence: 99%

Section: -Acetoxy-3amentioning

confidence: 99%

Section: -Acetoxy-3amentioning

confidence: 99%

mentioning

confidence: 99%

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Potential Corticoid Metabolites: Chemical Synthesis of 3- and 21-Monosulfates and Their Double-Conjugates of Tetrahydrocorticosteroids in the 5.ALPHA.- and 5.BETA.-Series

Okihara

Mitamura

Hasegawa

et al. 2010

CHEMICAL & PHARMACEUTICAL BULLETIN

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Electronic and Steric Ligand Effects in the Radical Polymerization of Vinyl Acetate Mediated by β‐Ketoiminate Complexes of Cobalt(II)

Kumar¹,

Li²,

Gnanou³

et al. 2009

Chemistry An Asian Journal

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Complexes Co[OC(Ph)CHC(Me)NAr](2) [Ar=Ph, 1; o,o'-C(6)H(3)Me(2) (Xyl), 2; p-C(6)H(4)CF(3), 3] are tested in the polymerization of vinyl acetate (VAc) initiated by V-70 (0.8 equiv) at 30 degrees C. Polymerization occurs without any notable induction time yielding PVAc with relatively low polydispersity, but with higher than expected M(n) values, which indicates inefficient trapping processes. The apparent polymerization rate constant varies in the order 2>1>3. Controlled polymer growth is also observed when the polymerization is conducted in the presence of a much higher V-70/1 ratio, demonstrating that this system can also function as a transfer agent in a degenerative transfer process. Competition between chain growth and catalyzed chain transfer (CCT) is also observed, the latter prevailing at higher temperatures. Comparison of these results with previous reports on bis(beta-diketonato) complexes allows a separate assessment of ligand electronic and steric effects in the ability to control polymerization.

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Fourier transform ion cyclotron resonance mass spectrometry using atmospheric pressure photoionization for high‐resolution analyses of corticosteroids

Greig

Bolaños

Quenzer

et al. 2003

Rapid Comm Mass Spectrometry

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Fourier transform ion cyclotron resonance mass spectrometry (FTICRMS) was coupled with atmospheric pressure photoionization (APPI) for the first time and used for the analysis of several corticosteroids.1 The analytes showed excellent response using APPI when compared with both electrospray ionization (ESI) and atmospheric pressure chemical ionization (APCI). APPI has the advantage of requiring less heat for desolvation, resulting in less thermal degradation of the analytes and higher signal-to-noise than APCI. In terms of ultimate sensitivity, APPI is more efficient than either ESI or APCI for the analysis of corticosteroids. With some compounds, the high-resolution capability of FTICRMS was necessary to obtain an accurate mass due to contributions of the M(+.) (13)C isotope in the [M+H](+) ion peak.

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Determination of natural corticosteroids in urine samples from sportsmen

Cited by 27 publications

References 6 publications

Potential Corticoid Metabolites: Chemical Synthesis of 3- and 21-Monosulfates and Their Double-Conjugates of Tetrahydrocorticosteroids in the 5.ALPHA.- and 5.BETA.-Series

Potential Corticoid Metabolites: Chemical Synthesis of 3- and 21-Monosulfates and Their Double-Conjugates of Tetrahydrocorticosteroids in the 5.ALPHA.- and 5.BETA.-Series

Electronic and Steric Ligand Effects in the Radical Polymerization of Vinyl Acetate Mediated by β‐Ketoiminate Complexes of Cobalt(II)

Fourier transform ion cyclotron resonance mass spectrometry using atmospheric pressure photoionization for high‐resolution analyses of corticosteroids

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