Mass spectral studies of deuterium-labelled picolinyl fatty esters in the determination of double-bond positions

The results of experimental studies of the composition of individual substances migrating from medical rubber plugs produced both in and abroad based on technical bromobutyl rubber are presented. The quantitative content of volatile organic compounds related to species impurities of gasoline was determined by gas chromatography from a standard glass bottle sealed with a sterile stopper based on bromobutyl rubber. The method of atomic emission spectroscopy was used to determine (indirect) the presence of organometallic, organosulfur and metal-inorganic compounds that did not pass through chromatographic columns, and the presence of organometallic, organosulfur and metal-inorganic compounds was determined by the content of metal and non-metal cations. The results of mass spectral studies of extracts of aqueous extracts from plugs based on bromobutyl rubber showed that they contain impurities of bromo-alkanes and bromo-arenes, which are direct-acting carcinogens.

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Mass spectral studies of 3,5-Diamino-1,2,4-thiadiazoles

Australian Journal of Chemistry ◽

10.1071/ch9770563 ◽

1977 ◽

Vol 30 (3) ◽

pp. 563 ◽

Cited By ~ 9

Author(s):

CP Joshua ◽

KN Rajasekharan

Keyword(s):

Electron Impact ◽

Structure Determination ◽

Mass Spectra ◽

Spectral Studies ◽

Mass Spectral ◽

Fragmentation Mechanisms

The mass spectra and fragmentation mechanisms of some 5-alkyl(or aryl)amino-3-amino-, 5-amino-3- arylamino-, 3,5-bis(arylamino)-, 4- aryl-3-arylamino-5-imino-4,5-dihydro-, and 3-alkyl(or aryl)amino-4- aryl-5-arylimino-4,5-dihydro-1,2,4-thiadiazoles and those of a 3-amino- 4-aryl-5-imino-4,5-dihydro-1,2,4-thiadiazole are discussed. The study, based on the behaviour of isomers under electron impact, attempts to evaluate the usefulness of mass spectra in structure determination of variously substituted 3,5-diamino-1,2,4-thiadiazoles.

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THE THYMOLYTIC ACTIVITY OF 6- AND 9-HALOCORTICOIDS AND RELATED STEROIDS

Acta Endocrinologica ◽

10.1530/acta.0.0490262 ◽

1965 ◽

Vol 49 (2) ◽

pp. 262-270 ◽

Cited By ~ 2

Author(s):

Ralph I. Dorfman ◽

P. G. Holton ◽

Fred A. Kind

Keyword(s):

Double Bond ◽

Subcutaneous Injection ◽

Fluocinolone Acetonide ◽

Relative Potency ◽

Subcutaneous Route ◽

Adrenalectomized Rats

ABSTRACT Adrenalectomized rats were used for the determination of the relative potency of various 6- and 9-halo substituted corticoids administered subcutaneously or by gavage using thymus weightas the endpoint. By subcutaneous injection, fluocinolone acetonide was the most active corticoid at 700 times that of cortisol. This compound was also the most active corticoid by the gavage route and was judged to be 570 times as active as the standard cortisol. The introduction of the 16,17-acetonide and 16,17-acetone 21-acetate groups into 17α,21-dihydroxy-9α,11β-dichloropregna-1,4-diene-3,20-dione increased the activity by a factor of 42 and 100, respectively. The introduction of the δ1 double bond into 6α-fluoroprogesterone 16,17-acetonide caused an increase of 10-fold in thymolytic activity assessed by the subcutaneous route

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Combination of programmable temperature vaporizer-large volume injection gas chromatography-mass spectrometry and automated mass spectral deconvolution and identification system for the determination of 32 pesticides in fruits and vegetables

Chinese Journal of Chromatography ◽

10.3724/sp.j.1123.2014.09005 ◽

2014 ◽

Vol 32 (12) ◽

pp. 1390

Author(s):

Zhaoyun CAO ◽

Renxiang MOU ◽

Li WU ◽

Xiaoyan LIN ◽

Zhiwei ZHU ◽

...

Keyword(s):

Mass Spectrometry ◽

Gas Chromatography ◽

Large Volume ◽

Fruits And Vegetables ◽

Gas Chromatography Mass Spectrometry ◽

Identification System ◽

Large Volume Injection ◽

Spectral Deconvolution ◽

Mass Spectral

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Gradient-Enhanced Inverse-Detected NMR Techniquesfor Determination of 1H-15N Coupling Constants in 2,2-Dimethylpenta-3,4-dienal Derivatives

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19971747 ◽

1997 ◽

Vol 62 (11) ◽

pp. 1747-1753 ◽

Cited By ~ 5

Author(s):

Radek Marek

Keyword(s):

Double Bond ◽

Chemical Shifts ◽

Multiple Bond ◽

Coupling Constants ◽

Single Quantum ◽

Nmr Techniques ◽

Phase Sensitive ◽

Heteronuclear Coupling

Determination of 15N chemical shifts and heteronuclear coupling constants of substituted 2,2-dimethylpenta-3,4-dienal hydrazones is presented. The chemical shifts were determined by gradient-enhanced inverse-detected NMR techniques and 1H-15N coupling constants were extracted from phase-sensitive gradient-enhanced single-quantum multiple bond correlation experiments. Stereospecific behaviour of the coupling constants 2J(1H,15N) and 1J(1H,13C) has been used to determine the configuration on a C=N double bond. The above-mentioned compounds exist predominantly as E isomers in deuteriochloroform.

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