Steroidal isomers with uniform mass spectra of their per-TMS derivatives: synthesis of 17-hydroxyandrostan-3-ones, androst-1-, and -4-ene-3,17-diols

New long-standing metabolites of 17α-methyltestosterone are detected in HepG2 cell in vitro metabolic model and in human urine

Novel metabolites of the anabolic androgenic steroid 17α-methyltestosterone have been detected in HepG2 cell in vitro metabolic model and in human urine. Their detection was accomplished through targeted gas chromatography-(tandem) mass spectrometry analysis that has been based on microscale synthesized standards. The related synthesis and the gas chromatography-(tandem) mass spectrometry characterization of the analytical standards are described. All newly presented metabolites have a fully reduced steroid A-ring with either an 17,17-dimethyl-18-nor-Δ13 structure or they have been further oxidized at position 16 of the steroid backbone. Metabolites with 17,17-dimethyl-18-nor-Δ13 structure may be considered as side products of phase II metabolic sulfation of the 17β-hydroxy group of methyltestosterone or its reduced tetrahydro-methyltestosterone metabolites 17α-methyl-5β-androstane-3α,17β-diol and 17α-methyl-5α-androstane-3α,17β-diol that produce the known epimeric 17β-methyl-5β-androstane-3α,17α-diol and 17β-methyl-5α-androstane-3α,17α-diol metabolites. The prospective of these new metabolites to increase detection time windows and improve identification was investigated by applying the World Anti-doping Agency TD2021IDCR criteria. The new metabolites, presented herein, complement the current knowledge on the 17α-methyltestosterone metabolism and in some cases can be used as additional long-term markers in the frame of sport doping drug testing.

Biotransformation of anabolic androgenic steroids in human skin cells

In comparison to well-known drug-metabolizing organs such as the liver, the metabolic capacity of human skin is still not well elucidated despite the widespread use of topical drug application. To gain a comprehensive insight into anabolic steroid metabolism in the skin, six structurally related anabolic androgenic steroids, testosterone, metandienone, methyltestosterone, clostebol, dehydrochloromethyltestosterone, and methylclostebol, were applied to human keratinocytes and fibroblasts derived from the juvenile foreskin. Phase I metabolites obtained from incubation media were analyzed by gas chromatography-mass spectrometry. The 5α-reductase activity was predominant in the metabolic pathways as supported by the detection of 5α-reduced metabolites after incubation of testosterone, methyltestosterone, clostebol, and methylclostebol. Additionally, the stereochemistry structures of fully reduced metabolites (4α,5α-isomers) of clostebol and methylclostebol were newly confirmed in this study by the help of inhouse synthesized reference materials. The results provide insights into the steroid metabolism in human skin cells with respect to the characteristics of the chemical structures.

Stereoselective Reduction of Steroidal 4-Ene-3-ketones in the Presence of Biomass-Derived Ionic Liquids Leading to Biologically Important 5β-Steroids

The stereoselective reduction of the steroidal 4-ene-3-ketone moiety (enone) affords the 5β-steroid backbone that is a key structural element of biologically important neuroactive steroids. Neurosteroids have been currently studied as novel and potent central nervous system drug-like compounds for the treatment of, e.g., postpartum depression. As a green methodology, we studied the palladium-catalyzed hydrogenation of steroidal 4-ene-3-ketones in the presence of ionic liquids derived from natural carboxylic acids. The hydrogenation proceeds with improved 5β-selectivity in the presence of tetrabutylammonium carboxylates as additives compared to the exclusive use of an organic solvent. Under optimal conditions, using tetrabutylammonium d-mandelate, the reduction of testosterone led to 5β-dihydrotestosterone in high yield and stereoselectivity and no byproduct formation was observed. Moreover, the catalyst could be recycled. The presence of additional substituents on the steroid backbone showed a significant effect on the 5β-selectivity.

Metabolomics workflow as a driven tool for rapid detection of metabolites in doping analysis. Development and validation

RATIONALE

This work demonstrates the high potential of combining high-resolution mass spectrometry with chemometric tools, using metabolomics as a guided tool for anti-doping analysis. The administration of 7-keto-DHEA was studied as a proof-of-concept of the effectiveness of the combination of knowledge-based and machine-learning approaches to differentiate the changes due to the athletic activities from those due to the recourse to doping substances and methods.

METHODS

Urine samples were collected from five healthy volunteers before and after an oral administration by identifying three time intervals. Raw data were acquired by injecting less than 1 μL of derivatized samples into a model 8890 gas chromatograph coupled to a model 7250 accurate-mass quadrupole time-of-flight analyzer (both from Agilent Technologies), by using a low-energy electron ionization source; the samples were then preprocessed to align peak retention times with the same accurate mass. The resulting data table was subjected to multivariate analysis.

RESULTS

Multivariate analysis showed a high similarity between the samples belonging to the same collection interval and a clear separation between the different excretion intervals. The discrimination between blank and long excretion groups may suggest the presence of long excretion markers, which are particularly significant in anti-doping analysis. Furthermore, matching the most significant features with some of the metabolites reported in the literature data demonstrated the rationality of the proposed metabolomics-based approach.

CONCLUSIONS

The application of metabolomics tools as an investigation strategy could reduce the time and resources required to identify and characterize intake markers maximizing the information that can be extracted from the data and extending the research field by avoiding a priori bias. Therefore, metabolic fingerprinting of prohibited substance intakes could be an appropriate analytical approach to reduce the risk of false-positive/negative results, aiding in the interpretation of "abnormal" profiles and discrimination of pseudo-endogenous steroid intake in the anti-doping field.

Controlled administration of dehydrochloromethyltestosterone in humans: Urinary excretion and long-term detection of metabolites for anti-doping purpose

Dehydrochloromethyltestosterone (DHCMT) is an anabolic-androgenic steroid that was developed by Jenapharm in the 1960s and was marketed as Oral Turinabol®. It is prohibited in sports at all times; nevertheless, there are several findings by anti-doping laboratories every year. New long-term metabolites have been proposed in 2011/12, which resulted in adverse analytical findings in retests of the Olympic games of 2008 and 2012. However, no controlled administration trial monitoring these long-term metabolites was reported until now. In this study, DHCMT (5 mg, p.o.) was administered to five healthy male volunteers and their urine samples were collected for a total of 60 days. The unconjugated and the glucuronidated fraction were analyzed separately by gas chromatography coupled to tandem mass spectrometry. The formation of the described long-term metabolites was verified, and their excretion monitored in detail. Due to interindividual differences there were several varieties in the excretion profiles among the volunteers. The metabolite M3, which has a fully reduced A-ring and modified D-ring structure, was identified by comparison with reference material as 4α-chloro-17β-hydroxymethyl-17α-methyl-18-nor-5α-androstan-13-en-3α-ol. It was found to be suitable as long-term marker for the intake of DHCMT in four of the volunteers. In one of the volunteers, it was detectable for 45 days after single oral dose administration. However, in two of the volunteers M5 (already published as long-term metabolite in the 1990s) showed longer detection windows. In one volunteer M3 was undetectable but another metabolite, M2, was found as the longest detectable metabolite. The last sample clearly identified as positive was collected between 9.9 and 44.9 days. Furthermore, the metabolite epiM4 (partially reduced A-ring and a modified D-ring structure which is epimerized in position 17 compared to M3) was identified in the urine of all volunteers with the help of chemically synthesized reference as 4-chloro-17α-hydroxymethyl-17β-methyl-18-nor-androsta-4,13-dien-3β-ol. It may serve as additional confirmatory metabolite. It is highly recommended to screen for all known metabolites in both fractions, glucuronidated and unconjugated, to improve identification of cheating athletes. This study also offers some deeper insights into the metabolism of DHCMT and of 17α-methyl steroids in general.

New Insights into the Metabolism of Methyltestosterone and Metandienone: Detection of Novel A-Ring Reduced Metabolites

Metandienone and methyltestosterone are orally active anabolic-androgenic steroids with a 17α-methyl structure that are prohibited in sports but are frequently detected in anti-doping analysis. Following the previously reported detection of long-term metabolites with a 17ξ-hydroxymethyl-17ξ-methyl-18-nor-5ξ-androst-13-en-3ξ-ol structure in the chlorinated metandienone analog dehydrochloromethyltestosterone ("oral turinabol"), in this study we investigated the formation of similar metabolites of metandienone and 17α-methyltestosterone with a rearranged D-ring and a fully reduced A-ring. Using a semi-targeted approach including the synthesis of reference compounds, two diastereomeric substances, viz. 17α-hydroxymethyl-17β-methyl-18-nor-5β-androst-13-en-3α-ol and its 5α-analog, were identified following an administration of methyltestosterone. In post-administration urines of metandienone, only the 5β-metabolite was detected. Additionally, 3α,5β-tetrahydro-epi-methyltestosterone was identified in the urines of both administrations besides the classical metabolites included in the screening procedures. Besides their applicability for anti-doping analysis, the results provide new insights into the metabolism of 17α-methyl steroids with respect to the order of reductions in the A-ring, the participation of different enzymes, and alterations to the D-ring.

Spectral trends in GC-EI-MS data obtained from the SWGDRUG mass spectral library and literature: A resource for the identification of unknown compounds

Rapid identification of new or emerging psychoactive substances remains a critical challenge in forensic drug chemistry laboratories. Current analytical protocols are well-designed for confirmation of known substances yet struggle when new compounds are encountered. Many laboratories initially attempt to classify new compounds using gas chromatography-electron ionization-mass spectrometry (GC-EI-MS). Though there is a large body of research focused on the analysis of illicit substances with GC-EI-MS, there is little high-level discussion of mass spectral trends for different classes of drugs. This manuscript compiles literature information and performs simple exploratory analyses on evaluated GC-EI-MS data to investigate mass spectral trends for illicit substance classes. Additionally, this work offers other important aspects: brief discussions of how each class of drugs is used; illustrations of EI mass spectra with proposed structures of commonly observed ions; and summaries of mass spectral trends that can help an analyst classify new illicit compounds.

Mass spectral fragmentation analyses of isotopically labelled hydroxy steroids using gas chromatography/electron ionization low-resolution mass spectrometry: A practical approach

RATIONALE

Gas chromatography coupled to electron ionization mass spectrometry (GC/EI-MS) is used for routine screening of anabolic steroids in many laboratories after the conversion of polar groups into trimethylsilyl (TMS) derivatives. The aim of this work is to elucidate the origin and formation of common and subclass-specific fragments in the mass spectra of TMS-derivatized steroids. Especially in the context of metabolite identification or analysis of designer drugs, isotopic labelling is helpful to better understand fragment ion generation, identify unknown compounds and update established screening methods.

METHODS

Stable isotope labelling procedures for the introduction of [² H₉ ]-TMS or ¹⁸ O were established to generate perdeuterotrimethylsilylated, mixed deuterated and ¹⁸ O-labelled derivatives for 13 different hydroxy steroids. Fragmentation proposals were substantiated by comparison of the abundances of isotopically labelled and unlabelled fragment ions in unit mass resolution GC/MS. Specific fragmentations were also investigated by high-resolution MS (GC/quadrupole time-of-flight MS, GC/QTOFMS).

RESULTS

Methyl radical cleavage occurs primarily from the TMS groups in saturated androstanes and from the steroid nucleus in the case of enol-TMS of oxo or α,β-unsaturated steroid ketones. Loss of trimethylsilanol (TMSOH) is dependent on steric factors, degree of saturation of the steroid backbone and the availability of a hydrogen atom and TMSO group in the 1,3-diaxial position. For the formation of the [M - 105]⁺ fragment ion, methyl radical cleavage predominates from the angular methyl groups in position C-18 or C-19 and is independent of the site of TMSOH loss. The common [M - 15 - 76]⁺ fragment ion was found in low abundance and identified as [M - CH₃ - (CH₃ )₂ SiH - OH]⁺ . For the different steroid subclasses further diagnostic fragment ions were discussed and structure proposals postulated.

CONCLUSIONS

Stable isotope labelling of oxo groups as well as derivatization with deuterated TMS groups enables the detection of structure-related fragment ion generation in unit mass resolution GC/EI-MS. This may in turn allow us to propose isomeric assignments that are otherwise almost impossible using MS only.

MASS SPECTROMETRIC FRAGMENTATION OF TRIMETHYLSILYL AND RELATED ALKYLSILYL DERIVATIVES

This review describes the mass spectral fragmentation of trimethylsilyl (TMS) and related alkylsilyl derivatives used for preparing samples for analysis, mainly by combined gas chromatography and mass spectrometry (GC/MS). The review is divided into three sections. The first section is concerned with the TMS derivatives themselves and describes fragmentation of derivatized alcohols, thiols, amines, ketones, carboxylic acids and bifunctional compounds such as hydroxy- and amino-acids, halo acids and hydroxy ethers. More complex compounds such as glycerides, sphingolipids, carbohydrates, organic phosphates, phosphonates, steroids, vitamin D, cannabinoids, and prostaglandins are discussed next. The second section describes intermolecular reactions of siliconium ions such as the TMS cation and the third section discusses other alkylsilyl derivatives. Among these latter compounds are di- and trialkyl-silyl derivatives, various substituted-alkyldimethylsilyl derivatives such as the tert-butyldimethylsilyl ethers, cyclic silyl derivatives, alkoxysilyl derivatives, and 3-pyridylmethyldimethylsilyl esters used for double bond location in fatty acid spectra. © 2019 Wiley Periodicals, Inc. Mass Spec Rev 0000:1-107, 2019.

Formation of 5α-dihydrotestosterone from 5α-androstane-3α,17β-diol in prostate cancer LAPC-4 cells - Identifying inhibitors of non-classical pathways producing the most potent androgen

5α-Dihydrotestosterone (5α-DHT) possesses a great affinity for the androgen receptor (AR), and its binding to AR promotes the proliferation of prostate cancer (PC) cells in androgen-dependent PC. Primarily synthesized from testosterone (T) in testis, 5α-DHT could also be produced from 5α-androstane-3α,17β-diol (3α-diol), an almost inactive androgen, following non-classical pathways. We reported the chemical synthesis of non-commercially available [4-¹⁴C]-3α-diol from [4-¹⁴C]-T, and the development of a biological assay to identify inhibitors of the 5α-DHT formation from radiolabeled 3α-diol in LAPC-4 cell PC model. We measured the inhibitory potency of 5α-androstane derivatives against the formation of 5α-DHT, and inhibition curves were obtained for the most potent compounds (IC₅₀ = 1.2-14.1 μM). The most potent inhibitor 25 (IC₅₀ = 1.2 μM) possesses a 4-(4-CF₃-3-CH₃O-benzyl)piperazinyl methyl side chain at C3β and 17β-OH/17α-CCH functionalities at C17 of a 5α-androstane core.

Fine-mapping of the substrate specificity of human steroid 21-hydroxylase (CYP21A2)

Cytochrome P450 enzymes (CYPs) are capable of catalyzing regio- and stereo-specific oxy functionalization reactions, which otherwise are major challenges in organic chemistry. In order to make the best possible use of these biocatalysts it is imperative to understand their specificities. Human CYP21A2 (steroid 21-hydroxylase) acts on the side-chain attached to C-17 in ring D of a steroid substrate, but the configuration of ring A also plays a prominent role in substrate cognition. Here, we comprehensively investigated this relationship using sixteen 17,17-dimethyl-18-nor-13-ene steroids with different arrangements of hydroxy-, oxo-, fluoro- and chloro-groups and in the presence or absence of double bonds (Δ1 and/or Δ4) and heteroatoms in ring A. The results show that presence of a 3-oxo group is a strict requirement for a CYP21A2 substrate, while the other configurations tested were all tolerated. This was also confirmed by control experiments using endogenous steroids. While progesterone and 17-hydroxyprogesterone were hydroxylated at C-21, (17-hydroxy-) pregnenolone did not react. Molecular docking experiments indicate that the interaction of the carbonyl group at C-3 to the side-chain Arg234 of the enzyme is indispensable.

Advances in the detection of designer steroids in anti-doping

The abuse of unknown designer androgenic anabolic steroids (AAS) is considered to be an issue of significant importance, as AAS are the choice of doping preference according to World Anti-doping Agency statistics. In addition, unknown designer AAS are preferred since the World Anti-doping Agency mass spectrometric identification criteria cannot be applied to unknown molecules. Consequently, cheating athletes have a strong motive to use designer AAS in order to both achieve performance enhancement and to escape from testing positive in anti-doping tests. To face the problem, a synergy is required between the anti-doping analytical science and sports anti-doping regulations. This Review examines various aspects of the designer AAS. First, the structural modifications of the already known AAS to create new designer molecules are explained. A list of the designer synthetic and endogenous AAS is then presented. Second, we discuss progress in the detection of designer AAS using: mass spectrometry and bioassays; analytical data processing of the unknown designer AAS; metabolite synthesis; and, long-term storage of urine and blood samples. Finally, the introduction of regulations from sports authorities as preventive measures for long-term storage and reprocessing of samples, initially reported as negatives, is discussed.

A new simple and high-yield synthesis of 5α-dihydrotestosterone (DHT), a potent androgen receptor agonist

We have devised an efficient procedure for the synthesis of 5α-dihydrotestosterone (DHT) (1) starting from 3β-hydroxy-5α-androstan-17-one, providing the product in unprecedented 82% yield. A reported method of using toxic Jones reagent is replaced by milder oxidizing agent (NMO/TPAP) in the synthesis of a key intermediate 17β-[(tert-butyldimethylsilyl)oxy]-5α-androstan-3-one (18). This new procedure is simple, does not require special apparatus/precautions or chromatographic purification in most of the steps.

Endocrine characterization of the designer steroid methyl-1-testosterone: investigations on tissue-specific anabolic-androgenic potency, side effects, and metabolism

Various products containing rarely characterized anabolic steroids are nowadays marketed as dietary supplements. Herein, the designer steroid methyl-1-testosterone (M1T) (17β-hydroxy-17α-methyl-5α-androst-1-en-3-one) was identified, and its biological activity, potential adverse effects, and metabolism were investigated. The affinity of M1T toward the androgen receptor (AR) was tested in vitro using a yeast AR transactivation assay. Its tissue-specific androgenic and anabolic potency and potential adverse effects were studied in a Hershberger assay (sc or oral), and tissue weights and selected molecular markers were investigated. Determination of M1T and its metabolites was performed by gas chromatography mass spectrometry. In the yeast AR transactivation assay, M1T was characterized as potent androgen. In rats, M1T dose-dependently stimulated prostate and levator ani muscle weight after sc administration. Oral administration had no effect but stimulated proliferation in the prostate and modulated IGF-I and AR expression in the gastrocnemius muscle in a dose-dependent manner. Analysis of tyrosine aminotransferase expression provided evidence for a strong activity of M1T in the liver (much higher after oral administration). In rat urine, 17α-methyl-5α-androstane-3α,17β-diol, M1T, and a hydroxylated metabolite were identified. In humans, M1T was confirmed in urine in addition to its main metabolites 17α-methyl-5α-androst-1-ene-3α,17β-diol and 17α-methyl-5α-androstane-3α,17β-diol. Additionally, the corresponding 17-epimers as well as 17β-hydroxymethyl-17α-methyl-18-nor-5α-androsta-1,13-dien-3-one and its 17-epimer were detected, and their elimination kinetics was monitored. It was demonstrated that M1T is a potent androgenic and anabolic steroid after oral and sc administration. Obviously, this substance shows no selective AR modulator characteristics and might exhibit liver toxicity, especially after oral administration.

Seized designer supplement named "1-Androsterone": identification as 3β-hydroxy-5α-androst-1-en-17-one and its urinary elimination

New analogues of androgens that had never been available as approved drugs are marketed as "dietary supplement" recently. They are mainly advertised to promote muscle mass and are considered by the governmental authorities in various countries, as well as by the World Anti-doping Agency for sport, as being pharmacologically and/or chemically related to anabolic steroids. In the present study, we report the detection of a steroid in a product seized by the State Bureau of Criminal Investigation Schleswig-Holstein, Germany. The product "1-Androsterone" of the brand name "Advanced Muscle Science" was labeled to contain 100mg of "1-Androstene-3b-ol,17-one" per capsule. The product was analyzed underivatized and as bis-TMS derivative by GC-MS. The steroid was identified by comparison with chemically synthesized 3β-hydroxy-5α-androst-1-en-17-one, prepared by reduction of 5α-androst-1-ene-3,17-dione with LS-Selectride (Lithium tris-isoamylborohydride), and by nuclear magnetic resonance. Semi-quantitation revealed an amount of 3β-hydroxy-5α-androst-1-en-17-one in the capsules as labeled. Following oral administration to a male volunteer, the main urinary metabolites were monitored. 1-Testosterone (17β-hydroxy-5α-androst-1-en-3-one), 1-androstenedione (5α-androst-1-ene-3,17-dione), 3α-hydroxy-5α-androst-1-en-17-one, 5α-androst-1-ene-3α,17β-diol, and 5α-androst-1-ene-3β,17β-diol were detected besides the parent compound and two more metabolites (up to now not finally identified but most likely C-18 and C-19 hydroxylated 5α-androst-1-ene-3,17-diones). Additionally, common steroids of the urinary steroid profile were altered after the administration of "1-Androsterone". Especially the ratios of androsterone/etiocholanolone and 5α-/5β-androstane-3α,17β-diol and the concentration of 5α-dihydrotestosterone were influenced. 3α-Hydroxy-5α-androst-1-en-17-one appears to be suitable for the long-term detection of the steroid (ab-)use, as this characteristic metabolite was detectable in screening up to nine days after a single administration of one capsule.

Sports-related issues and biochemistry of natural and synthetic anabolic substances

Testosterone is the principal male sex hormone. As with all natural steroids, it is biosynthesized from cholesterol. Phase I metabolism employs some very specific enzymes and pathways. Phase II metabolism and excretion follow more general patterns. The effects of testosterone are twofold: anabolic and androgenic. Because of its anabolic effects, testosterone is frequently abused in sports. Because of its endogenous nature, testosterone doping is difficult to detect. The standard procedure is based on the evaluation of the urinary steroid profile. Conspicuous samples then are submitted to compound-specific (13)C/(12)C analysis. Synthetic and endogenous steroids differ in this measure. Numerous xenobiotic compounds have been derived from testosterone. The modifications typically aim at a reduction of the androgenic properties while maintaining the anabolic potential. Most of these compounds have been withdrawn from the legal market. However, they are found to be illicitly added to otherwise inefficient nutritional supplements. These products represent a major problem to doping control. Recently, clinical trials with selective androgen receptor modulators have been started.

Metabolism of androsta-1,4,6-triene-3,17-dione and detection by gas chromatography/mass spectrometry in doping control

The urinary metabolism of the irreversible aromatase inhibitor androsta-1,4,6-triene-3,17-dione was investigated. It is mainly excreted unchanged and as its 17beta-hydroxy analogue. For confirmation, 17beta-hydroxyandrosta-1,4,6-trien-3-one was synthesized and characterized by nuclear magnetic resonance (NMR) in addition to the parent compound. In addition, several reduced metabolites were detected in the post-administration urines, namely 17beta-hydroxyandrosta-1,4-dien-3-one (boldenone), 17beta-hydroxy-5beta-androst-1-en-3-one (boldenone metabolite), 17beta-hydroxyandrosta-4,6-dien-3-one, and androsta-4,6-diene-3,17-dione. The identification was performed by comparison of the metabolites with reference material utilizing gas chromatography/mass spectrometry (GC/MS) of the underivatized compounds and GC/MS and GC/tandem mass spectrometry (MS/MS) of their trimethylsilyl (TMS) derivatives. Alterations in the steroid profile were also observed, most obviously in the androsterone/testosterone ratio. Even if not explicitly listed, androsta-1,4,6-triene-3,17-dione is classified as a prohibited substance in sports by the World Anti-Doping Agency (WADA) due to its aromatase-inhibiting properties. In 2006 three samples from human routine sports doping control tested positive for metabolites of androsta-1,4,6-triene-3,17-dione. The samples were initially found suspicious for the boldenone metabolite 17beta-hydroxy-5beta-androst-1-en-3-one. Since metabolites of androst-4-ene-3,6,17-trione were also present in the urine samples, it is presumed that these findings were due to the administration of a product like 'Novedex Xtreme', which could be easily obtained from the sport supplement market.

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.