Chromatographic-mass spectrometric study of antitumor preparations (oxazaphosphorines) using electron impact and chemical ionization

1983 ◽  
Vol 18 (6) ◽  
pp. 699-702
Author(s):  
Yu. P. Reva ◽  
F. A. Medvedev
Keyword(s):  
Electron Impact ◽  
Chemical Ionization ◽  
Mass Spectrometric Study ◽  
Mass Spectrometric ◽  
Spectrometric Study ◽  
Chromatographic Mass

Gas chromatographic—mass spectrometric study of reactions of halodeoxycelluloses with thiols in aqueous solutions

1995 ◽  
Vol 27 (1) ◽  
pp. 13-21 ◽  
Author(s):  
Nobuyoshi Aoki ◽  
Katsuya Koganei ◽  
Hu-Sheng Chang ◽  
Ken-ichi Furuhata ◽  
Munenori Sakamoto
Keyword(s):  
Aqueous Solutions ◽  
Mass Spectrometric Study ◽  
Mass Spectrometric ◽  
Spectrometric Study ◽  
Chromatographic Mass

scholarly journals Gas chromatographic-mass spectrometric study of metabolites of C21 and C19 steroids in neonatal porcine testicular microsomes

1985 ◽  
Vol 227 (3) ◽  
pp. 909-916 ◽  
Author(s):  
T K Kwan ◽  
N F Taylor ◽  
D Watson ◽  
D B Gower
Keyword(s):  
Mass Spectrometry ◽  
Gas Chromatography ◽  
Mass Spectrometric Study ◽  
Mass Spectrometric ◽  
Spectrometric Study ◽  
Selected Ion Monitoring ◽  
17 Hydroxyprogesterone ◽  
Porcine Testis ◽  
Steroid Pathway ◽  
Chromatographic Mass

Microsomal fractions obtained from testes of 3-week-old piglets have been incubated, separately, with progesterone, 17-hydroxyprogesterone, 5-pregnene-3 beta,20 beta-diol, 16 alpha-hydroxypregnenolone, 5-androstene-3 beta,17 alpha-diol and dehydro-epiandrosterone. The metabolites, after derivatization, have been separated by capillary gas chromatography and identified by mass spectrometry. Quantification was by selected ion monitoring. Progesterone was shown to be 17-hydroxylated and also converted into 4,16-androstadien-3-one (androstadienone). The major metabolite of 17-hydroxyprogesterone was 4-androstene-3,17-dione (4-androstenedione), but little, if any, androstadienone was formed, indicating that this particular biosynthesis did not require 17-hydroxylation. The metabolites of 5-pregnene-3 beta, 20 beta-diol were found to be 17-hydroxypregnenolone, 3 beta-hydroxy-5,16-pregnadien-20-one (16-dehydropregnenolone) and 5,16-androstadien-3 beta-ol. Dehydroepiandrosterone and 5-androstene-3 beta,17 alpha-diol were interconvertible but neither steroid acted as a substrate for 16-androstene formation. However, dehydroepiandrosterone was metabolized to a small quantity of 4-androstenedione. Under the conditions used, no metabolites of 16 alpha-hydroxypregnenolone could be detected. The present results, together with those obtained earlier, indicate that the neonatal porcine testis has the capacity to synthesize weak androgens, mainly by the 4-en-3-oxo steroid pathway. Although 16-androstenes cannot be formed from C19 steroids, progesterone served as a substrate and may be converted directly to androstadienone, without being 17-hydroxylated first. The pathway to 5,16-androstadien-3 beta-ol, however, involves 17-hydroxypregnenolone and 16-dehydropregnenolone as intermediates.

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