Microbial transformation of (+)-androsta-1 ,4-diene-3,17-dione by Cephalosporium aphidicola

Fermentation of (+)-androsta-1,4-diene-3,17-dione ([structure: see text]) with Cephalosporium aphidicola for 8 days yielded oxidative and reductive metabolites, androst-4-ene-3,17-dione ([structure: see text]), 17beta-hydroxyandrosta-1,4-diene-3-one ([structure: see text]), 11alpha-hydroxyandrosta-1,4-diene-3,17-dione ([structure: see text]), 11alpha-hydroxyandrost-4-ene-3,17-dione ([structure: see text]), 11alpha,17beta-dihydroxyandrost-4-ene-3-one ([structure: see text]) and 11alpha,17beta-dihydroxyandrosta-1,4-diene-3-one ([structure: see text]). The fermentation of [structure: see text] with Fusarium lini also yielded metabolites [structure: see text]. The structures of these metabolites were elucidated on the basis of spectroscopic techniques.     

Microbial hydroxylation of pregnenolone derivatives

Pregnenolone and pregnenolone acetate were incubated with the fungi Cunninghamella elegans, Rhizopus stolonifer and Gibberella fujikuroi. Incubation of with C. elegans yielded metabolites, 3beta,7beta,11alpha-trihydroxypreg-5-en-20-one, 3beta,6alpha,11alpha,12beta,15beta-pentahydroxypreg-4-en-20-one and 3beta,6beta,11alpha-trihydroxypreg-4-en-20-one, while incubation with G. fujikuroi yielded two known metabolites, 3beta,7beta-dihydroxypregn-5-en-20-one and 6beta,15beta-dihydroxypreg-4-ene-3,20-dione. Metabolites and were found to be new. Fermentation of by C. elegans yielded four known oxidative metabolites, androsta-1,4-diene-3,17-dione, 6beta,15beta-dihydroxyandrost-4-ene-3,17-dione and 11alpha,15beta-dihydroxypreg-4-ene-3,20-dione. Fermentation of with R. stolonifer yielded two known metabolites, 11alpha-hydroxypreg-4-ene-3,20-dione and. Compounds were screened for their cholinesterase inhibitory activity in a mechanism-based assay.     

Microbial transformation of dehydroepiandrosterone

Transformation of dehydroepiandrosterone (DHEA) (1) was carried out by a plant pathogen Rhizopus stolonifer, which resulted in the production of seven metabolites. These metabolites were identified as 3beta,17beta-dihydroxyanandrost-5-ene (2), 3beta,17beta-dihydroxyandrost-4ene (3), 17beta-hydroxyandrost-4-ene-3-one (4), 3beta,11-dihydroxyandrost-4-ene-17-one (5), 3beta,7alpha-dihydroandrost-5-ene-17-one (6), 3A,7alpha,17beta-trihydroxyandrost-5-ene (7) and 11beta-hydroxyandrost-4,6-diene-3,17-dione (8). The structures of the transformed products were determined by the spectroscopic techniques.     

Testosterone metabolism revisited: discovery of new metabolites

The metabolism of testosterone is revisited. Four previously unreported metabolites were detected in urine after hydrolysis with KOH using a liquid chromatography–tandem mass spectrometry method and precursor ion scan mode. The metabolites were characterized by a product ion scan obtained with accurate mass measurements. Androsta-4,6-dien-3,17-dione, androsta-1,4-dien-3,17-dione, 17-hydroxy-androsta-4,6-dien-3-one and 15-androsten-3,17-dione were proposed as feasible structures for these metabolites on the basis of the mass spectrometry data. The proposed structures were confirmed by analysis of synthetic reference compounds. Only 15-androsten-3,17-dione could not be confirmed, owing to the lack of a commercially available standard. That all four compounds are testosterone metabolites was confirmed by the qualitative analysis of several urine samples collected before and after administration of testosterone undecanoate. The metabolite androsta-1,4-dien-3,17-dione has a structure analogous to that of the exogenous anabolic steroid boldenone. Specific transitions for boldenone and its metabolite 17β-hydroxy-5β-androst-1-en-3-one were also monitored. Both compounds were also detected after KOH treatment, suggesting that this metabolic pathway is involved in the endogenous detection of boldenone previously reported by several authors.     

The anaerobic degradation of deoxycholic acid by PSEUDOMONAS SP. NCIB 10590

The anaerobic metabolism of deoxycholic acid by Pseudomonas sp. NCIB 10590 was studied. The metabolic pathway was similar to that operating under aerobic conditions with 12β-hydroxyandrosta-1,4-dien-3,17-dione as the major neutral product an metabolites which are not produced during aerobic metabolism were isolated and evidence is presented for the following structures: 9α-hydroxyandrost-1-en-3,17-dione, 12α,17)β-dihydroxyandrosta-1,4-dien-3-one; 3β,12β-dihydroxy-5β-androstan-17-one an formation and significance of the phenolic secosteroid is discussed.     

Degradation of deoxycholic acid by Pseudomonas Sp. NCIB 10590

The microbial degradation of deoxycholic acid 1 by Pseudomonas NCIB 10590 has been studied and two major products have been isolated and identified as 12β-hydroxyandrosta-1,4-dien-3,17-dione 2 and 12α-hydroxypregna-1,4-dien-3-one-20-carboxylic acid 9. Three minor products were isolated and evidence is given for the following structures: 12α-hydroxyandrosta-1,4-dien-3,17-dione 4, 12β-hydroxyandrosta-4-en-3,17-dione 7 and 12?, 17?-dihydroxyandrosta-1,4-dien-3-one 8.     

6alpha-Methylandrostenedione: gas chromatographic mass spectrometric detection in doping control

In recent years products containing 6alpha-methylandrost-4-ene-3,17-dione have appeared on the sport supplement market. Scientific studies have proven aromatase inhibition and anabolic and mild androgenic properties; however, no preparation has been approved for medical use up to now. In sports 6alpha-methylandrost-4-ene-3,17-dione has to be classified as a prohibited substance according to the regulations of the World Anti-Doping Agency (WADA). For the detection of its misuse the metabolism was studied following the administration of two preparations obtained from the Internet (Formadrol and Methyl-1-Pro). Several metabolites as well as the parent compounds were synthesized and the structures of 3alpha-hydroxy-6alpha-methyl-5beta-androstan-17-one, 6alpha-methylandrost-4-ene-3,17-dione, and 5beta-dihydromedroxyprogesterone were confirmed by nuclear magnetic resonance (NMR) spectroscopy. The main metabolite, 3alpha-hydroxy-6alpha-methyl-5beta-androstan-17-one, was found to be excreted as glucuronide and was still detectable in microg/mL amounts until urine collection was terminated (after 25 h). Additionally, samples from routine human sports doping control had already tested positive for the presence of metabolites of 6alpha-methylandrost-4-ene-3,17-dione. Screening analysis can be easily performed by the existing screening procedure for anabolic steroids using 3alpha-hydroxy-6alpha-methyl-5beta-androstan-17-one as target substance (limit of detection <10 ng/mL). Its discrimination from the closely eluting drostanolone metabolite, 3alpha-hydroxy-2alpha-methyl-5alpha-androstan-17-one, is possible as the mono-TMS derivative.     

Metabolic studies of methenolone acetate in horses

Methenolone acetate (17β-acetoxy-1-methyl-5α-androst-1-en-3-one), a synthetic anabolic steroid, is frequently abused in human sports. It is preferred for its therapeutic efficiency and lower hepatic toxicity compared with its 17α-alkylated analogs. As with other anabolic steroids, methenolone acetate may be used to enhance performance in racehorses. Metabolic studies on methenolone acetate have been reported for humans, whereas little is known about its metabolic fate in horses. This paper describes the investigation of in vitro and in vivo metabolism of methenolone acetate in racehorses.Studies on the in vitro biotransformation of methenolone acetate with horse liver microsomes were carried out. Methenolone (M1, 1-methyl-5α-androst-1-en-17β-ol-3-one) and seven other metabolites (M2-M8) were detected in vitro. They were 1-methyl-5α-androst-1-ene-3,17-dione (M2), 1-methyl-5α-androst-1-en-6-ol-3,17-dione (M3) and two stereoisomers of 1-methylen-5α-androstan-2-ol-3,17-dione (M4 and M5), 1-methyl-5α-androst-1-en-16-ol-3,17-dione (M6) and monohydroxylated 1-methyl-5α-androst-1-en-17-ol-3-one (M7 and M8). After oral administration of Primobolan^® (80 tablets × 5 mg of methenolone acetate each) to two thoroughbred geldings, the parent steroid ester was not detected in the post-administration urine samples. However, seven metabolites, namely M1, M6-M8, two stereoisomers of M7 (M9 and M10) and 1-methyl-5α-androst-1-en-17α-ol-3-one (M11), could be detected. The metabolic pathway for methenolone acetate is postulated. This study has shown that metabolite M1 could be targeted for controlling the abuse of methenolone acetate in horses.     

Detection of androst-4-ene-3,6,17-trione (6-OXO) and its metabolites in urine by gas chromatography-mass spectrometry in relation to doping analysis

The metabolism and excretion of androst-4-ene-3,6,17-trione after administration of the 'nutritional' supplement 6-OXO was investigated by gas chromatography-mass spectrometry (GC-MS) in full-scan mode. The parent drug androst-4-ene-3,6,17-trione and androst-4-ene-6alpha,17beta-diol-3-one and androst-4-ene-6alpha-ol-3,17-dione were detected in the post-administration urine samples. Because androst-4-ene-3,6,17-trione is an anabolic steroid and an aromatase inhibitor, this substance is regarded as a doping agent. Hence, a selective and sensitive GC-MS method in selected ion monitoring mode for the detection of the TMS-enol-TMS-ether derivatives of these substances was developed and validated for doping control purposes. The limit of detection (LOD) of the investigated compounds ranged from 5 to 10 ng/mL. Using this method, the detection time for androst-4-ene-3,6,17-trione and androst-4-ene-6alpha,17beta-diol-3-one was 24 h, while androst-4-ene-6alpha-ol-3,17-dione could be detected up to 37 h after administration of the dose recommended by the manufacturer.     

Epoxide compounds ofβ,β-dialkyl divinyl ketones and unsaturatedβ-methoxy ketones

By the epoxidation with alkaline hydrogen peroxide of 5-methylhepta-1,4-dien-3-one and 5-ethylhepta-1, 4-dien-3-one and the 3-methyl-7-methoxyhept-3-en-5-one and 3-ethyl-7-methoxyhept-3-en-5-one formed from them, we have obtained the mono- and diepoxy ketones corresponding to them with yields of 48–65%. It has been shown that under the influence of zinc chloride 4, 5-epoxy-3-methyl-7-methoxyheptan-5-one forms 3-methyl-7-methoxyheptane-4,5-dione and 3-methylhept-1-ene-3,4-dione. Under the same conditions, 4,5-epoxy-3-ethyl-7-methoxyheptan-5-one is converted into 3-ethyl-7-methoxyheptane-4,5-dione and 3-ethylhept-1-ene-3, 4-dione. 3-Methyl- and 3-ethylheptene-3,4-diones are also formed in the distillation of the methyl and ethyl methoxy diketones in the presence of p-toluenesulfonic acid. The IR spectra of the compounds synthesized have been recorded.     

Fractionation of free and conjugated steroids for the detection of boldenone metabolites in calf urine with ultra-performance liquid chromatography/tandem mass spectrometry

For over a decade there has been an intensive debate on the possible natural origin of boldenone (androst-1,4-diene-17beta-ol-3-one, 17beta-boldenone) in calf urine and several alternative markers to discriminate between endogenously formed boldenone and exogenously administered boldenone have been suggested. The currently approved method for proving illegal administration of beta-boldenone(ester) is the detection of beta-boldenone conjugates. In the presented method the sulphate, glucuronide and free fractions are separated from each other during cleanup on a SAX column to be able to determine the conjugated status of the boldenone metabolites. The sulphate and glucuronide fractions are submitted to hydrolysis and all three fractions are further cleaned up on a combination of C18/NH2 solid-phase extraction (SPE) columns. Chromatographic separation of the boldenone metabolites was achieved with a Waters Acquity UPLC instrument using a Sapphire C18 (1.7 microm; 2x50 mm) column within 5 min. Detection of the analytes was achieved by electrospray ionisation tandem mass spectrometry. The decision limits of this method, validated according to Commission Decision 2002/657/EC, were 0.08 ng mL(-1) for androsta-1,4-diene-3,17-dione, 0.13 ng mL(-1) for androst-4-ene-3,17-dione, 0.11 ng mL(-1) for 17alpha-boldenone, 0.07 ng mL(-1) for 17beta-boldenone, 0.24 ng mL(-1) for 5beta-androst-1-en-17beta-ol-3-one and 0.58 ng mL(-1) for 6beta-hydroxy-17beta-boldenone. Because of the fractionation approach used in this method there is no need for conjugated reference standards which often are not available. The disadvantage of needing three analytical runs to determine the conjugated status of each of the metabolites was overcome by using fast chromatography.     

The high resolution mass spectra of α,β-unsaturated and α-chloromercuri-α,β-unsaturated steroidal ketones

The high resolution mass spectra (500 eV) of some α,β-unsaturated steroidal ketones have been studied and compared with the spectra of the corresponding α-chloromercuri ketones. In the latter, the carbon-mercury bond frequently remains intact at the expense of the fission of two carbon-carbon bonds. The abundance of mercury-containing ions allows the use of the mercury atom fingerprint in confirming ring B fragmentation of the steroid nucleus at C(6)–C(7) and C(9)–C(10) for 5α-androst-1-ene-3,17-dione, 1,4-androstadiene-3,17-dione and their 2-chloromercuri derivatives; and at C(7)–C(8) and C(9)–C(10) for 1,4,6-androstatriene-3,17-dione, 1,4,6-androstarien-17 β-ol-3-one and their 2-chloromercuri derivatives. 2-Chloromercuri-1,4,6-androstatriene-3,17-dione and 2-chloromercuri-1,4,6-androstatrien-17 β-ol-3-one also give an abundant ion as the result of ring C fragmentation at C(8)–C(14) and C(11)–C(12), the chloromercuri group being replaced by a hydrogen atom. This ring C cleavage gives the only recognizable distinctive fragmentation ion for 1,4,6-pregnatriene-3,20-dione and 2-chloromercuri-1,4,6-pregnatriene-3,20-dione. For most of the mercurated steroids, the low resolution mass spectra (70 eV) are reported. In these spectra, the fragmentation patterns are similar to those obtained using the higher ionization energy employed for the high resolution spectra.     

Norchlorotestosterone Acetate: An Alternative Metabolism Study and GC–MS<Superscript>2</Superscript> Analysis in Kidney Fat,Urine, and Faeces

Norchlorotestosterone acetate (NClTA) is an anabolic steroid which resembles chlorotestosterone acetate. It cannot yet be detected by routine methods used for anabolic steroids, because there is no knowledge of its metabolic pathway. The invertebrate Neomysis integer has been used as an alternative model to study the metabolism of NClTA. The experimental results indicated the presence of 4-norchloroandrost-4-ene-17-ol-3-one (NClT) and 4-norchloroandrost-4-ene-3,17-dione (NorClAD) as possible metabolites of NClTA. Subsequently NClTA and the synthesised metabolites NClT and NorClAD were incorporated into the routine multi-residue method for detection of anabolic steroids in kidney fat, urine, and faeces.     

Epoxidation and reduction of DHEA, 1,4,6-androstatrien-3-one and 4,6-androstadien-3beta,17beta-diol

Dehydroepiandrosterone (DHEA) reacted with m-chloroperoxybenzoic acid(m-CPBA) to form 3beta-hydroxy-5alpha,6alpha-epoxyandrostan-17-one (1), but it did not react with 30% H2O2. 1,4,6-Androstatrien-3,17-dione (2) was obtained from DHEA and 2,3-dichloro-5,6-dicyano-1,4-benzoquinone in dioxane. Compound 2 was reacted with 30%H2O2 and 5% NaOH in methanol to give 1alpha,2alpha-epoxy-4,6-androstadien-3,17-dione (3),which was stereoselectively reduced with NaBH4 to form 1alpha,2alpha-epoxy-4,6-androstadien-3beta,17beta-diol (7) and reacted with Li metal in absolute ethanol-tetrahydrofuran mixture to give 2-ethoxy-1,4,6-androstatrien-3,17-dione (8). Compound 2 was also epoxidized with m-CPBA in dichloromethane to afford 6alpha,7alpha-epoxy-1,4-androstadien-3,17-dione (4),which was reacted with NaBH4 to synthesize 6alpha,7alpha-epoxy-4-androsten-3beta,17beta-diol (9).Compound 4 was reduced with Li metal in absolute ethanol-tetrahydrofuran mixture to form 7beta-ethoxy-6alpha-hydroxy-1,4-androstadien-3,17-dione (10). Compound 2 was reduced with NaBH4 in absolute ethanol to form 4,6-androstadien-3beta,17beta-diol (5), which was reacted with 30% H2O2 to give the original compound, but which reacted with m-CPBAto give 4beta,5beta-epoxy-6-androsten-3beta,17beta-diol (6).     

Microbial transformation of (+)-adrenosterone

The microbial transformation of (+)-adrenosterone (1) by Cephalosporium aphidicola afforded three metabolites identified as androsta-1,4-diene-3,11,17-trione (2), 17beta-hydroxyandrost-4-ene-3,11-dione (3) and 17beta-hydroxyandrosta-1,4-diene-3,11-dione (4). The fermentation of 1 with Fusarium lini also produced metabolites 2 and 4, while the fermentation with Trichothecium roseum afforded metabolite 3. The structures of transformed products were determined by spectroscopic methods.     

Synthesis of deuterium-labeled 16 alpha,19-dihydroxy C19 steroids as internal standards for gas chromatography-mass spectrometry.

[2 beta,7,7,16 beta-2H4]16 alpha,19-Dihydroxyandrost-4-ene-3,17-dione (14) and [7,7,16 beta-2H3]3 beta,16 alpha,19-trihydroxyandrost-5-en-17-one (16), with high isotopic purity, respectively, were synthesized from unlabeled 3 beta-(tert-butyldimethylsiloxy)-androst-5-ene-17 beta-yl acetate (1). The deuterium introduction at C-7 was carried out by reductive deoxygenation of the 7-keto compound 3 with dichloroaluminum deuteride and that at C-2 beta and/or C-16 beta by controlled alkaline hydrolysis of 16-bromo-17-ketone 11 or 12 with NaOD in D2O and pyridine. [7,7-2H2]3 beta-Hydroxyandrost-5-en-17-one (6), obtained from compound 1 by a five-step sequence, was converted to compound 14 or 16 by an eight-step or seven-step sequence, respectively. The labeled steroids 14 and 16 are useful as internal standards for gas chromatography-mass spectrometry analysis of the endogenous levels.     

Studies related to the origin of C18 neutral steroids isolated from extracts of urine from the male horse: the identification of urinary 19-oic acids and their decarboxylation to produce estr-4-en-17beta-ol-3-one (19-nortestosterone) and estr-4-ene-3,17-dione (19-norandrost-4-ene-3,17-dione) during sample processing

For almost two decades we have known that enzymatic hydrolysis of "normal" urine samples from the entire male horse using Escherichia coli (E. coli) followed by solvolysis (ethyl acetate:methanol:sulphuric acid) results in the detection of significant amounts of estr-4-ene-3,17-dione (19-norandrost-4-ene-3,17-dione) along with estr-4-en-17beta-ol-3-one (19-nortestosterone, nandrolone) in extracts of the hydrolysed urine and that both steroids are isolated from the solvolysis fraction. This solvolysis process is targeted at the steroid sulphates. Also we have shown that 19-norandrost-4-ene-3,17-dione and 19-nortestosterone are isolated from testicular tissue extracts. Subsequently, evidence was obtained that 19-nortestosterone detected in extracts of "normal" urine from male horses may not be derived from the 17beta-sulphate conjugate. However, following administration of 19-nortestosterone based proprietary anabolic steroids to all horses (males, females and castrates), the urinary 19-nortestosterone arising from the administration is excreted primarily as the 17beta-sulphate conjugate. Thus, if the 19-nortestosterone-17beta-sulphate conjugate arises only following administration this has interesting implications for drug surveillance programmes to control administration of 19-nortestosterone based anabolic preparations to male horses. These results have led us to consider that the precursors to 19-nortestosterone and 19-norandrost-4-ene-3,17-dione, present in the urine prior to the hydrolysis steps, have the same basic structure except for the functionality at the 17-position. We have used preparative high pressure liquid chromatography (LC) and LC fractionation to separate these precursors from the high amounts of oestrogenic sulphates present in "normal" urine from the entire male horse. Purified fractions have then been studied by liquid chromatography-mass spectrometry (LC-MS) and gas chromatography-mass spectrometry (GC-MS) to identify the precursors.     

Identification of 4-hydroxyandrost-4-ene-3,17-dione metabolites in prostatic cancer patients by liquid chromatography-mass spectrometry.

Liquid chromatography with thermospray mass spectrometry has proved to be an invaluable technique for the study of metabolic degradation of xenobiotics in complex biological fluids. This paper describes the detection of 4-hydroxyandrost-4-ene-3,17-dione and its metabolites in urinary extracts from prostatic cancer patients. Several metabolites were detected including 4 beta,5 alpha-dihydroxyandrostan-3,17-dione, 3,17-dihydroxyandrostan-4-ones and 3 alpha-hydroxy-5 beta-androstan-4,17-dione.     

Microbial transformation of prednisone

The microbial transformation of prednisone (17alpha,21-dihydroxy-pregna-1,4-diene-3,11,20-trione) (1) by Cunninghamella elegans afforded two metabolites, 17alpha,21-dihydroxy-5alpha-pregn-1-ene-3,11,20-trione (2) and 17alpha,20S,21-trihydroxy-5alpha-pregn-1-ene-3,11-dione (3), while the fermentation of 1 with Fusarium lini, Rhizopus stolonifer and Curvularia lunata afforded a metabolite 1,4-pregnadiene-17alpha,20S,21-triol-3,11-dione (4). Compound 3 was found to be a new metabolite. Their structures were elucidated on the basis of spectroscopic techniques. Compound 3 showed inhibitory activity against lipoxygenase enzyme.     

Photochemistry of desonide, a non-fluorinated steroidal anti-inflammatory drug

The photochemistry of anti-inflammatory drug desonide (De, 1) was studied in aerobic as well as in anaerobic condition with different irradiation wavelengths (254, 310 nm) in acetonitrile and 2-propanol. All photoproducts obtained were isolated and characterized on the basis of IR, (1)H-, (13)C-NMR spectroscopy and elemental analysis study. The products were: 11beta,21-dihydroxy-16alpha,17alpha-(1-methylethylidenedioxy)-1,5-cyclopregn-3-ene-2,20-dione 2 (254 nm), 11beta-hydroxy-16alpha,17alpha-(1-methylethylidenedioxy)androsta-1,4-diene-3-one 3 (310 nm/2-propanol), 17beta-hydroperoxy-11beta-hydroxy-16alpha,17alpha-(1-methylethylidenedioxy)androsta-1,4-diene-3-one 4 (310 nm/O(2)/2-propanol). Cyclohexadienone moiety in ring A and keto group at C(17) were found to be deeply modified by UV light therefore, loss of biological activity both during storage and in vivo can not be ruled out.