Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Mass steroids

Oxandrolone was reported to stack well with so -called mass steroids such as testosterone or with high anabolic/moderate androgenic steroids such as Equipoise or Nandrolones. Persons over 40 have reported excellent results by stacking 15-25 mg of Oxandrolone daily with 200-400 mg of Deca. [Pg.28]

Combined with so- called mass steroids, Masteron did aid in a rapid build-up of strength and mass even with its relatively moderate anabolic qualities. However, Masteron was not reported to be the best choice for this purpose by those polled. DHT can promote hair loss and prostate disorders in prone individuals though it is not well documented as to whether or not deviants of the DHT structure can in all case do the same. [Pg.38]

This accurate measurement of the ratio of abundances of isotopes is used for geological dating, estimation of the ages of antiquities, testing athletes for the use of banned steroids, examining fine details of chemical reaction pathways, and so on. These uses are discussed in this book under various headings concerned with isotope ratio mass spectrometry (see Chapters 7, 14, 15, 16, 17, 47, and 48). [Pg.341]

The field of steroid analysis includes identification of steroids in biological samples, analysis of pharmaceutical formulations, and elucidation of steroid stmctures. Many different analytical methods, such as ultraviolet (uv) spectroscopy, infrared (ir) spectroscopy, nuclear magnetic resonance (nmr) spectroscopy, x-ray crystallography, and mass spectroscopy, are used for steroid analysis. The constant development of these analytical techniques has stimulated the advancement of steroid analysis. [Pg.448]

A definitive method for stmctural deterrnination is x-ray crystallography. Extensive x-ray crystal stmcture deterrninations have been done on a wide variety of steroids and these have been collected and Hsted (270). In addition, other analytical methods for steroid quantification or stmcture determination include, mass spectrometry (271), polarography, fluorimetry, radioimmunoassay (264), and various chromatographic techniques (272). [Pg.448]

The general reaction procedure and apparatus used are exactly as described in Procedure 2. Ammonia (465 ml) is distilled into a 2-liter reaction flask and to this is added 165mlofisopropylalcoholandasolutionof30g(0.195 mole) of 17/ -estradiol 3-methyl ether (mp 118.5-120°) in 180 ml of tetrahydrofuran. The steroid is only partially soluble in the mixture. A 5 g portion of sodium (26 g, 1.13 g-atoms total) is added to the stirred mixture and the solid dissolves in the light blue solution within several min. As additional metal is added, the mixture becomes dark blue and a solid (matted needles) separates. Stirring is inefficient for a few minutes until the mass of crystals breaks down. All of the sodium is consumed after 1 hr and 120 ml of methanol is then added to the mixture with care. The product is isolated as in Procedure 4h 2. After being air-dried, the solid weighs 32.5 g (ca. 100% for a monohydrate). A sample of the material is dried for analysis and analyzed as described in Procedure 2 enol ether, 91% unreduced aromatics, 0.3%. The crude product may be crystallized from acetone-water or preferably from hexane. [Pg.50]

It has been reported that exchange of protons activated by enolization can be performed directly in a glass inlet system of the mass spectrometer prior to analysis by heating the sample at about 200° with deuterium oxide vapor for a few minutes. " Exchange has been observed with 2-, 3-, 6-, 11- and 17-keto steroids, but the resulting isotopic purity is usually poor,... [Pg.151]

Under certain conditions surface catalytic deuterations can lead to the exchange of benzylic hydrogens. An example in the steroid field is the exchange of the benzylic hydrogens in estrone methyl ether (42) with deuterium in the presence of palladized charcoal." " According to mass spectrometric analysis, the product (43) contains three deuteriums (83 %), which have been assigned to the 6- and 9a-positions on the basis of NMR evidence." " ... [Pg.157]

During the course of a mass spectrometric study of D-homo-14-hydroxy steroids, it was necessary to prepare the corresponding C-8 deuterium labeled analogs. The preparation of these uncommon steroid derivatives has been achieved by repeating the Torgov total synthesis [(257) (262)] with a deuterium-labeled bicyclic starting material (258). Both of the resulting 14-hydroxy epimers, (261) and (262), exhibited better than 90% isotopic purity. ... [Pg.210]

In gas chromatography/mass spectrometry (GC/MS), the effluent from a gas chromatograph is passed into a mass spectrometer and a mass spectrum is taken every few milliseconds. Thus gas chromatography is used to separate a mixture, and mass spectrometry used to analyze it. GC/MS is a very powerful analytical technique. One of its more visible applications involves the testing of athletes for steroids, stimulants, and other performance-enhancing drugs. These drugs are converted in the body to derivatives called metabolites, which are then excreted in the... [Pg.573]

D. BaiTon, J. Barbosa, J. A. Pascual and J. Segura, Dkect deteimination of anabolic steroids in human urine by online solid-phase extraction/liquid cliromatography/mass specti ometi y , 7. Mass Spectrom. 31 309-319 (1996). [Pg.296]

The positive-ion mass spectrum of somalin, a steroid linked to a 2,... [Pg.213]

B. Characteristic Fragment Ions The most characteristic cleavage is the loss of carbons 15,16, and 17, together with the side chain and one additional hydrogen. It is possible to determine the elemental composition of the side chains of steroids by the difference in the mass between the molecular ion and an intense ion more than 15... [Pg.119]

Anabolic steroids increase muscle mass and strength. They are used by some athletes to enhance performance. [Pg.75]

The use of anabolic steroids to promote an increase in muscle mass and strength has become a serious problem. Anabolic Steroids are not intended for this use. Unfortunately, deathsin young, healthy individuals have been directly attributed to the use of these drugs Nurses should discourage the illegal use of anabolic steroids to increase muscle mass... [Pg.540]

John, a friend of your brother, has started to use anabolic steroids to increase his strength and muscle mass... [Pg.557]

SlEKMANN L (1979) Determination of steroid hormones by the use of isotope dilution mass spectrometry a definitive method in clinical chemistry. J Steroid Biochem 11 117-123. [Pg.152]

Applications APCI-MS is often more widely applicable than ESI-MS to the analysis of classes of compounds with a low molecular weight, such as basic drugs and their metabolites, antibiotics, steroids, oestrogens, benzodiazepines, pesticides, surfactants, and most other organic compounds amenable to El. LC-APCI-MS has been used to analyse PET extracts obtained by a disso-lution/precipitation procedure [147]. Other applications of hyphenated APCI mass spectrometric techniques are described elsewhere LC-APCI-MS (Section 7.33.2) and packed column SFC-APCI-MS (Section 73.2.2) for polar nonvolatile organics. [Pg.383]

An alternative to the rotating disk method in a quiescent fluid is a stationary disk placed in a rotating fluid. This method, like the rotating disk, is based on fluid mechanics principles and has been studied using benzoic acid dissolving into water [30], Khoury et al. [31] applied the stationary disk method to the study of the mass transport of steroids into dilute polymer solutions. Since this method assumes that the rotating fluid near the disk obeys solid body rotation, the stirring device and the distance of the stirrer from the disk become important considerations when it is used. A similar device was developed by Braun and Parrott [32], who used stationary spherical tablets in a stirred liquid to study the effect of various parameters on the mass transport of benzoic acid. [Pg.114]

Mauger et al. [35] used the rotating filter assembly to assess the mass transport kinetics of particle populations of a steroid and demonstrated the applicability of a proposed diffusion model used to interpret the data. [Pg.115]

In view of our results obtained in reactions of the tetrahalogeno-benzynes with aromatic compounds we carried out a reaction of tetra-fluorobenzyne with the A-ring aromatic steroid 3,l7,fl-dimethoxy-oestra-l(10),2,4-triene (119) 154>. As we expected the initially formed enol-ethers were very rapidly hydrolysed and the adducts were isolated as the ketones (120) and (121). The mass spectra of the compounds (120) and (121) did not show molecular ion peaks and as anticipated the ketones were rapidly converted into the naphthalenes (122) and (123) photo-chemically. [Pg.69]

Hanselman TA, Graetz DA, Wilkie AC, Szabo NJ, Diaz CS (2006) Determination of steroidal estrogens in flushed dairy manure wastewater by gas chromatography-mass spectrometry. J Environ Qual 35 695-700... [Pg.107]

Combalbert S, Pype ML, Bemet N, Hemandez-Raquet G (2010) Enhanced methods for conditioning, storage, and extraction of liquid and solid samples of manure for determination of steroid hormones by solid-phase extraction and gas chromatography-mass spectrometry. Anal Bioanal Chem 398 973-984... [Pg.108]

Liquid chromatography-(tandem) mass spectrometry of selected emerging pollutants (steroid sex hormones, drugs and alkyl phenolic surfactants) in the aquatic environment [56]... [Pg.16]


See other pages where Mass steroids is mentioned: [Pg.573]    [Pg.1099]    [Pg.223]    [Pg.578]    [Pg.111]    [Pg.132]    [Pg.146]    [Pg.151]    [Pg.1099]    [Pg.119]    [Pg.119]    [Pg.119]    [Pg.120]    [Pg.956]    [Pg.357]    [Pg.359]    [Pg.112]    [Pg.394]    [Pg.820]    [Pg.142]    [Pg.283]    [Pg.110]    [Pg.44]    [Pg.121]    [Pg.403]    [Pg.228]    [Pg.228]   
See also in sourсe #XX -- [ Pg.384 ]




SEARCH



Genetic Disorders of Steroid Metabolism Diagnosed by Mass Spectrometry

Liquid chromatography-mass spectrometry anabolic steroids

Mass neuroactive steroids

Mass spectra of steroidal

Mass spectroscopy Steroids

Steroidal alkaloids, mass spectra

Tandem mass spectrometry anabolic steroids

© 2024 chempedia.info