Synthesis and characterization of 6ß-hydroxyandrosterone and 6ß-hydroxyetiocholanolone conjugated with glucuronic acid.

The detection of testosterone (T) misuse by doping control laboratories is mainly based on monitoring urinary T phase I metabolites released after enzymatic hydrolysis of the corresponding phase II glucuronide metabolites by gas chromatography (tandem) mass spectrometry (GC-MS(/MS)) methods. However, this strategy fails to properly determine two recently reported phase II metabolites of T conjugated with glucuronic acid that remained mostly conjugated after the hydrolysis step. These metabolites were identified as glucuronides of 6ß-hydroxyandrosterone (6ß-OH-And) and 6ß-hydroxyetiocholanolone (6ß-OH-Etio) but their exact conjugation site remained undetermined. In this study, the four possible glucuronides of 6ß-OH-And and 6ß-OH-Etio were synthesized and characterized by nuclear magnetic resonance (NMR) spectroscopy. Moreover, their chromatographic properties and MS spectra were compared to those obtained for the urine samples collected after administration of T. Results confirmed that the recently reported metabolites were the 3α-glucuronides of 6ß-OH-And and 6ß-OH-Etio. The synthesis and the elucidation of the exact structure of the metabolites presented in this study are crucial steps for the development of analytical methods in order to explore their role in T metabolism and their potential usefulness as biomarkers of T misuse.

The regio- and stereo-selective reduction of steroidal 4-en-3-ones using Na2S2O4/NaHCO3 and CuCl/NaBH4.

This paper describes the regio- and stereoselective reduction of △4-3-keto moiety in certain steroids using Na2S2O4/NaHCO3 and CuCl/NaBH4, respectively. Using either one of the two reduction agents in the reaction, the 17-substituents in the D ring were observed to have clearly influenced the stereoselective reduction of 4-ene in the A ring by the so-called conformational transmission effect. Na2S2O4/NaHCO3 regioselectively reduced CC at 4-position of 17-substituted-androst-4-en-3-one derivatives to 5α-H-3-one as the main isomer. And as an extended application, Epiandrosterone (11) was further synthesized from androst-4-en-3,17-dione (AD) via four steps. The total yield from this was about 45%. In the presence of CuCl/NaBH4, △4-3-keto conjugated reduction of 17-spirocyclic ethylene ketal protected androst-4-en-3-one derivatives mainly produced 3α-hydroxy-5ß-H isomers, at a yield around 81%. Considering the scaffold configuration of 3α-hydroxy-5ß-H moiety coincided with that of bile acid analogs, this selective reduction could also be used as an alternative method for the synthetic study of bile acids using AD and its derivatives, which are from the microorganism degradation of natural sterols, as the potential materials. Meanwhile, configurations of the reductive compounds 5b, 6b, 9, 10 and 17e were identified by X-ray diffraction.

Synthesis of 3-spiromorpholinone androsterone derivatives as inhibitors of 17ß-hydroxysteroid dehydrogenase type 3.

Spiromorpholinone derivatives were synthesized from androsterone or cyclohexanone in 6 or 3 steps, respectively, and these scaffolds were used for the introduction of a hydrophobic group via a nucleophilic substitution. Non-steroidal spiromorpholinones are not active as inhibitors of 17ß-hydroxysteroid dehydrogenase type 3 (17ß-HSD3), but steroidal morpholinones are very potent inhibitors. In fact, those with (S) stereochemistry are more active than their (R) homologues, whereas N-benzylated compounds are more active than their non substituted precursors. The target compounds exhibited strong inhibition of 17ß-HSD3 in rat testis homogenate (87-92% inhibition at 1 µM).

Synthesis of novel 16-spiro steroids: spiro-7'-(aryl)tetrahydro-1H-pyrrolo[1,2-c][1,3]thiazolo-trans-androsterone hybrid heterocycles.

The 1,3-dipolar cycloaddition of azomethine ylide derived in situ from the reaction of acenaphthylene-1,2-dione and 1,3-thiazolane-4-carboxylic acid to various exocyclic dipolarophiles synthesized from trans-androsterone and trans-dehydroandrosterone afforded a library of novel spiro[5'.2″]acenaphthylene-1″-one-spiro[16.6']-(7'-aryl)-tetrahydro-1H-pyrrolo [1,2-c][1,3]thiazolo-trans-androsterone/dehydroandrosterone hybrid heterocycles respectively. These reactions proceeded stereo-specifically affording a single isomer of the 16-spiro steroids in excellent yields.

Synthesis and preliminary bioevaluation of 99mTc(CO)3-17α-triazolylandrost-4-ene-3-one derivative prepared via click chemistry route.

Azolyl steroids are known to manifest antiprostate cancer and antiandrogenic activities. These azolyl steroids have been shown to express affinity toward androgen receptors (ARs) overexpressed on LNCaP (human prostate adenocarcinoma) cell line. Hence, suitably derivatized azolyl steroids can be envisaged as potential vectors for targeting overexpression of ARs in prostate cancer. In the present study, testosterone has been derivatized to 17α-azidoandrost-4-ene-3-one using microwave-mediated azidation of the mesylate. Subsequently, a facile one-pot Cu(I)-catalyzed Click reaction was carried out to synthesize (99m)Tc(CO)(3)-labeled 17α-triazolylandrost-4-ene-3-one, which was characterized by HPLC. The chemical characterization of (99m)Tc(CO)(3)-17α-triazolylandrost-4-ene-3-one was carried out by preparing its corresponding rhenium complex using [NEt(4)](2)[Re(CO)(3)Br(3)] precursor. The radiolabeled complex could be prepared in >95% radiochemical yield as determined by HPLC. In vitro studies of (99m)Tc(CO)(3)-17α-triazolylandrost-4-ene-3-one complex in LNCaP cell lines overexpressing ARs showed binding of 4.95%±1.2%, with inhibition of 8%±0.9%. In vivo biodistribution studies in male Wistar rats have shown uptake in the prostate to the extent of 0.48%±0.19% injected dose/g at 1 hpi and retention therein till 3 hpi. The present study demonstrates a novel and facile one-pot reaction for preparation of (99m)Tc-labeled 17α-triazolylandrost-4-ene-3-one complex using Click chemistry. The corresponding Re-analog has been prepared for purpose of comparative characterization with the (99m)Tc-labeled complex. The radiosynthetic strategy described in this article can be further extended toward preparation of radiolabeled complexes of other triazolyl steroidal derivatives.

The reaction of azoles with 17-chloro-16-formylandrosta-5,16-dien-3ß-yl-acetate: synthesis and structural elucidation of novel 16-azolylmethylene-17-oxoandrostanes.

The synthesis and structural elucidation, by 1D and 2D NMR and X-ray diffraction techniques, of novel E/Z 16-azolylmethylene-17-oxoandrostanes 2-9 prepared from the Vilsmeier-Hack reaction product 17-chloro-16-formylandrosta-5,16-dien-3ß-yl acetate 1 is reported. The reaction proceeds with pyrrole and pyrrole-alike nitrogen heterocycles such as 7-azaindole, indole, and 3-methylindole, in DMF, at 80°C, in the presence of K(2)CO(3), and allowed the attachment of privileged heterocyclic moieties, through the nitrogen atom to the steroid core at C16 via a methine carbon bridge, which is unprecedented in the literature and of potential synthetic and biological interest. Considerations on the possible reaction mechanism are included. All the synthesized compounds are new and are currently being tested for biological activities.

Synthesis of 7ß-hydroxy-epiandrosterone.

The synthesis of 7ß-hydroxy-epiandrosterone (6) possessing strong anti-inflammatory properties was achieved starting from 3ß-acetoxy-17,17-(ethylenedioxy)-5-androsten (1). This approach involved as a main step an allylic oxidation of the C-7 followed by two reduction reactions of the double bond and of the carbonyl group. This stereoselective synthesis in 5 steps gave 7ß-hydroxy-epiandrosterone in 63% overall yield.

Genotoxic, cytostatic, antineoplastic and apoptotic effects of newly synthesized antitumour steroidal esters.

In this study, we have investigated the genotoxic, cytostatic, antineoplastic and apoptotic effects of three newly synthesized modified steroidal esters, having as alkylating agent p-N,N-bis(2-chloroethyl) aminophenyl butyrate (CHL) or p-N,N-bis(2-chloroethyl) aminophenyl acetate (PHE) esterified with the steroidal nucleus modified in the B- and D-ring. The genotoxic and cytotoxic effects of the compounds were investigated both in vitro, in lymphocyte cultures obtained from blood samples of healthy donors and in vivo, in ascites cells of P388 leukemia obtained from the peritoneal cavity of DBA/2 mice. Preparations were scored for sister-chromatid exchange (SCE) and proliferation-rate indices (PRI). The newly synthesized compounds were also studied for antineoplastic activity against lymphocytic P388 and lymphoid L1210 leukemias in mice, by calculating the mean of the median survival of the drug-treated animals (T) versus the untreated control (C) (T/C%). The activity of caspase-2 and caspase-3, indicators of apoptosis, was assessed biochemically in primary cultures of human lymphocytes. Our results show that the newly synthesized compounds caused severe genotoxic effects by significantly increasing the frequency of SCE and decreasing the PRI values in cultures of peripheral lymphocytes in vitro and in ascites cells of lymphocytic P388 leukemia in vivo. A significant correlation was also observed in both the in vitro and in vivo experiments: the higher the SCE frequency the lower the PRI value (r=-0.65, P<0.001 and r=-0.99, P<0.01, respectively). The measured antileukemic potency was statistically increased by all test compounds in both types of tumours, while the activity of caspase-2 and caspase-3 showed a statistically significant increase after two periods of exposure. The genotoxic (increase of SCE), cytostatic/cytotoxic (decrease of PRI) and antileukemic effects (increase of T/C%) in combination with the induction of apoptosis (activation of caspase-2 and caspase-3) caused by the newly synthesized compounds, lead us to propose them as agents with potentially antineoplastic properties.

Dehydroepiandrosterone, epiandrosterone and synthetic derivatives inhibit Junin virus replication in vitro.

In the present paper the in vitro antiviral activity of dehydroepiandrosterone (DHEA), epiandrosterone (EA) and 16 synthetic derivatives against Junin virus (JUNV) replication in Vero cells was studied. DHEA and EA caused a selective inhibition of the replication of JUNV and other members of the Arenaviridae family such as Pichinde virus and Tacaribe virus. The compounds were not virucidal to cell-free JUNV. The impairment of viral replication was not due to an inhibitory effect of the steroids on virus adsorption or internalization. An inhibitory effect of the compounds on JUNV protein synthesis and both intracellular and extracellular virus production was demonstrated. A partial inhibitory action on cell surface expression of JUNV glycoprotein G1 was also detected on DHEA- and EA-treated cultures. Like DHEA and EA, three compounds obtained from EA by chemical synthesis showed selectivity indexes higher than ribavirin, the only antiviral compound that has shown partial efficacy against arenavirus infections.

Synthesis and analytics of 2,2,3,4,4-d5-19-nor-5alpha-androsterone--an internal standard in doping analysis.

A short and efficient synthesis of pentadeuterated 2,2,3,4,4-d5-19-nor-5alpha-androsterone 7 starting from 19-norandrost-4-ene-3,17-dione 1 by a d1-L-Selectride mediated stereo- and regioselective reduction of the 3-keto group is presented. The use of compound 7 as internal standard for the detection of anabolic steroids via mass spectrometric techniques such as gas chromatography-mass spectrometry (GC-MS) is discussed.

Enhanced activity of 3alpha-hydroxysteroid dehydrogenase by addition of the co-solvent 1-butyl-3-methylimidazolium (L)-lactate in aqueous phase of biphasic systems for reductive production of steroids.

The enzyme activity of 3alpha-hydrosteroid dehydrogenase (HSDH) was enhanced by the addition of the co-solvent 1-butyl-3-methylimidazolium (L)-lactate ([Bmim][lactate]) to 50 mM Tris-HCl buffer. When utilizing [Bmim][lactate], the reaction velocity of HSDH increased. Also, reductive production of androsterone was investigated in an aqueous-organic solvent biphasic system containing 5% [Bmim][lactate] as the co-solvent of aqueous phase. In a coupled-enzyme system comprising HSDH and formate dehydrogenase (FDH), a two-fold increase in production rate of androsterone was obtained when utilizing [Bmim][lactate] with NADH regeneration.

3Beta-alkyl-androsterones as inhibitors of type 3 17beta-hydroxysteroid dehydrogenase: inhibitory potency in intact cells, selectivity towards isoforms 1, 2, 5 and 7, binding affinity for steroid receptors, and proliferative/antiproliferative activities on AR+ and ER+ cell lines.

Type 3 17beta-hydroxysteroid dehydrogenase (17beta-HSD) is involved in the biosynthesis of the potent androgen testosterone (T), which plays an important role in androgen-sensitive diseases. In an attempt to design compounds to lower the level of T, we designed androsterone (ADT) derivatives substituted at the position 3beta as inhibitors of type 3 17beta-HSD, and then selected the eight most potent ones (compounds 1-8) for additional studies. In an intact cell assay, they inhibited efficiently the conversion of natural substrate 4-androstene-3,17-dione into T, although they were less active in intact cells (IC50 approximately 1 microM) than in homogenated cells (IC50=57-100 nM). A study of the inhibitory potency with four other 17beta-HSDs revealed they were selective, since they do not inhibit reductive types 1, 5 and 7, nor oxidative type 2. Interestingly, they did not show any binding affinity for steroid receptors (androgen, estrogen, glucocorticoid and progestin). Only two inhibitors, 3beta-phenyl-ADT (5) and 3beta-phenylmethyl-ADT (6) showed some proliferative activities on an AR+ cell line and on an ER+ cell line, but their effects were not mediated through the androgen or estrogen receptors. This study identified selective inhibitors of type 3 17beta-HSD acting through a mixed-type inhibition, and devoid of non-suitable androgenic and estrogenic proliferative activities. The more potent inhibitors were 3beta-hexyl-ADT (2), 3beta-cyclohexylethyl-ADT (4) and 3beta-phenylethyl-ADT (7).

Androsterone 3alpha-ether-3beta-substituted and androsterone 3beta-substituted derivatives as inhibitors of type 3 17beta-hydroxysteroid dehydrogenase: chemical synthesis and structure-activity relationship.

Type 3 17beta-hydroxysteroid dehydrogenase (17beta-HSD) is involved in the biosynthesis of androgen testosterone. To produce potent inhibitors of this key steroidogenic enzyme, we prepared a series of androsterone (ADT) derivatives by adding a variety of substituents at position 3. The 3beta-substituted ADT derivatives proved to be good inhibitors (IC(50) = 57-147 nM) with better inhibitory activities obtained for compounds bearing a propyl, s-butyl, cyclohexylalkyl, or phenylalkyl group. With an IC(50) value of 57 nM, the 3beta-phenylmethyl-ADT was 6-fold more potent than ADT, the lead compound, and 13-fold more potent than 4-androstene-3,17-dione, the natural enzyme substrate used itself as inhibitor. The 3alpha-ether-3beta-substituted ADT derivatives had a lower inhibitory activity compared to the 3beta-substituted ADT analogues except for the 3beta-phenylethyl-3alpha-methl-O-ADT (IC(50) = 73 nM), which proved to be a more potent inhibitor than 3beta-phenylethyl-ADT (IC(50) = 99 nM). The results of our study identified potent type 3 17beta-HSD inhibitors for potential use in the treatment of androgen-sensitive diseases.

First synthesis of a pentadeuterated 3'-hydroxystanozolol--an internal standard in doping analysis.

The first synthesis of 16,16,20,20,20-pentadeuterio-3'-hydroxystanozolol (8) in 26% yield over nine steps is described using moderately priced starting materials and economic amounts of reagents. Compound 8 can be used as an internal standard in screening procedures for anabolic steroids as well as for the quantification of stanozolol metabolites via mass spectrometric techniques, such as LC-MS or gas chromatography-mass spectrometry (GC-MS).

A facile and high yielding synthesis of 2,2,3,4,4-d5-androsterone-beta-D-glucuronide--an internal standard in dope.

A facile six-step synthesis of 2,2,3,4,4-d5-androsterone-beta-D-glucuronide (1) starting from epiandrosterone (2) in 63% yield is described and compared with several alternative synthetic pathways. Compound 1 can be used as an internal standard in screening procedures for anabolic steroids to monitor the hydrolysis step of the steroid glucuronides prior to gas chromatography-mass spectrometry (GC-MS) analysis. Thus, a time consuming solid-phase extraction step to remove possible hydrolysis inhibitors can be omitted.

Androsterone derivatives substituted at position 16: chemical synthesis, inhibition of type 3 17beta-hydroxysteroid dehydrogenase, binding affinity for steroid receptors and proliferative/antiproliferative activity on Shionogi (AR+) cells.

A series of androsterone (ADT) derivatives substituted at position 16 were efficiently synthesized in short reaction sequences; the ether analogues were also synthesized in the case of the methyl and allyl derivatives. The aim of this study was to develop inhibitors of the steroidogenic enzyme type 3 17beta-hydroxysteroid dehydrogenase and then evaluate their ability to inhibit this activity in transfected HEK-293 cells. For each compound we measured the percentage of inhibition of the transformation of 4-androstene-3,17-dione, the natural substrate of this steroidogenic enzyme, into the active androgen testosterone. The synthesized compounds proved to be weak inhibitors of this enzyme, but interestingly, these ADT derivatives do not bind to androgen, estrogen, glucocorticoid, and progestin receptors, suggesting no unsuitable receptor-mediated effects. One exception, 16alpha-(3'-bromopropyl)-5alpha-androstane-3alpha,17beta-diol, the only compound bearing a hydroxy group at position 17beta instead of a ketone, showed a strong binding affinity for the androgen receptor (70% at 1 microM) and also exhibited an antiproliferative activity on Shionogi (AR+) cells (86% at 1 microM), which was comparable to that of hydroxyflutamide, a pure antiandrogen (100% at 1 microM).

Syntheses and advanced NMR structure determination of androsteno-[17,16-d]-pyrimidine derivatives.

Reactions of 16-hydroxymethylene- and 16-aminomethylene-3beta-hydroxy-5-androsten-17-one with formamide and guanidine were carried out resulting in the formation of [16,17-d]-pyrimidine rings. Advanced two-dimensional NMR methods were used to investigate the structure of the products. Homonuclear-, and heteronuclear chemical shift correlation experiments yielded the complete 1H-, 13C- and 15N signal assignment for these compounds.

Sultamo-steroid analogues, Part VII: Synthesis of epi-androsterone derivatives with potential activity.

The reaction of epi-androsterone with cyanoacetyl hydrazine (2) gave the hydrazone derivative 3. The reactivity of 3 towards chemical reagents was studied to give pyridine, thiazole and thiophene derivatives.

Vía alternativa para la síntesis del 3-etilencetal-androsta-3, 17-diona / Alternative pathway for the synthesis of 3-ethylencetal-androsta-3, 17 dione

Se reporta una vía alternativa para la síntesis del 3-etilencetal-androsta-3, 17-diona, el cual es un intermedio importante para la obtención de corticoides por construcción de la cadena lateral de 17-ceto esteroides. En nuestro caso, partiendo de la androsta-4-ene-3, 17-diona, se obtuvo el producto deseado en 3 pasos de síntesis con buenos rendimientos

Transformation of epiandrosterone into 3-oxa-, 3-thia-, 3-selena-, and 3-aza-17-oxaandrostanes of the 5 alpha series based on beta-scission of alkoxyl radicals.

3 beta-Hydroxy-5 alpha-androstan-17-one was transformed into 17-oxa-5 alpha-androstan-3 beta-ol in five steps involving conversion of the 17-ketone via the corresponding lactol to its hypoiodite and thence a regioselective beta-scission under irradiation to give ring D seco iodoformate, from which the 17-oxasteroids were derived. Four bisheterosteroids 3,17-dioxa-5 alpha-androstane, 3-thia-17-oxa-5 alpha-androstane, 3-aza-17-oxa-5 alpha-androstane, and 3-selena-17-oxa-5 alpha-androstane) were synthesized from 17-oxa-5 alpha-androstan-3 beta-ol via 5, 8, 8, and 9 steps, respectively, involving a second regioselective beta-scission of an alkoxyl radical as the key step.