A chemoenzymatic process for preparation of highly purified dehydroepiandrosterone in high space-time yield.

Dehydroepiandrosterone (DHEA) is an important neurosteroid hormone to keep human hormonal balance and reproductive health. However, DHEA was always produced with impurities either by chemical or biological method and required high-cost purification before the medical use. To address this issue, a novel chemoenzymatic process was proposed and implemented to produce DHEA. An acetoxylated derivate of 4-androstene-3,17-dione (4-AD) was generated by chemical reaction and converted into DHEA by an enzyme cascade reaction combining a hydrolysis reaction with a reduction reaction. The hydrolysis reaction was catalyzed by a commercial esterase Z03 while the reduction reaction was catalyzed by E. coli cells co-expressing a 3ß-hydroxysteroid dehydrogenase SfSDR and a glucose dehydrogenase BtGDH. After the condition optimization, DHEA was synthesized at a 100 mL scale under 100 mM of substrate loading and purified as white powder with the highest space-time yield (4.80 g/L/h) and purity (99 %) in the biosynthesis of DHEA. The successful attempt in this study provides a new approach for green synthesis of highly purified DHEA in the pharmaceutical industry.

In vitro, ex vivo and in vivo short-term screening of DHEA nitrate derivatives activity over Trypanosoma cruzi Ninoa and TH strains from Oaxaca State, México.

Chagas disease is a health problem that affects millions of persons, currently Nifurtimox (Nfx) and Benznidazole (Bz) are the unique drugs to treat it. However, these drugs produce adverse effects and high toxicity, which has motivated the search for new candidate drugs. Based on reports about the extensive biological activity of steroidal nitrate esters, in this study three nitrate esters steroids (1b, 2b and 4b) were synthetized and characterized from Dehydroepiandrosterone (DHEA, 1a), 19-hydroxy-DHEA (2a), and Androst-5-en-3ß,17ß-diol (4a), respectively. In addition, compounds 3a and 3b were obtained by introducing an α-ethynyl and a ß-hydroxyl groups at position 17 of 2b and further nitration of the hydroxyl group. The trypanocidal activity of these steroids was evaluated in vitro against the epimastigote stage of two T. cruzi strains, Ninoa and TH, and their cytotoxicity over J774.2 macrophage cell line was assayed. Compounds 3a, 3b, and 4a shown higher trypanocidal activity than Bz and Nfx against epimastigotes of Ninoa strain, whereas DHEA (1a) and its nitrate derivative 1b showed higher activity than the reference drugs against the TH strain epimastigote. None of the compounds showed activity in the ex vivo assays against the blood trypomastigote of both strains. Interestingly, the selectivity index of Androst-5-en-3ß,17ß-diol 4a was almost twice the value of Nfx and 50 times more than Bz, against Ninoa and TH strains, respectively. Therefore, compound 4a could represent a valuable starting point toward the optimization of steroid derivatives as trypanocidal agents.

Dehydroepiandrosterone derived imidazolium salts and their antimicrobial efficacy.

Hybrid molecules consisting of steroid-imidazolium salts reveal interesting biological properties, especially regarding antimicrobial activities. Novel dehydroepiandrosterone derived imidazolium salts (11 salts) with side chains of different lengths were obtained in an efficient and straightforward synthetic route. Antimicrobial properties of new salts were examined by determining their minimum inhibitory concentrations (MICs). They were studied against several strains of bacteria, including clinical isolates of MRSA, and fungi. New compounds showed high activity against Gram-positive bacteria and Candida albicans as well as good compatibility with the representatives of the host cells when applied at concentrations corresponding to MIC value. The studies indicated high antimicrobial efficacy of imidazolium salts against the above-mentioned microorganisms with low hemolytic activity at a concentration that restricts the growth of the microorganisms. The interference of salts with the immune defense system, the influence on the biological activity of monocytes/macrophages measured by their viability and metabolic activity was also studied. The new compounds have shown immunoprotective properties.

Steroidal[17,16-d]pyrimidines derived from dehydroepiandrosterone: A convenient synthesis, antiproliferation activity, structure-activity relationships, and role of heterocyclic moiety.

A series of steroidal[17,16-d]pyrimidines derived from dehydroepiandrosterone were designed and prepared by a convenient heterocyclization reaction. The in vitro anticancer activities for these obtained compounds were evaluated against human cancer cell lines (HepG2, Huh-7, and SGC-7901), which demonstrated that some of these heterocyclic pyrimidine derivatives exhibited significantly good cytotoxic activities against all tested cell lines compared with 5-fluorouracil (5-FU), especially, compound 3b exhibited high potential growth inhibitory activities against all tested cell lines with the IC50 values of 5.41 ± 1.34, 5.65 ± 1.02 and 10.64 ± 1.49 µM, respectively, which might be used as promising lead scaffold for discovery of novel anticancer agents.

Peptidomimetics Based On Dehydroepiandrosterone Scaffold: Synthesis, Antiproliferation Activity, Structure-Activity Relationship, and Mechanisms.

A series of novel peptidomimetics bearing dehydroepiandrosterone moiety were designed, synthesized, and evaluated for their inhibition activities against cell proliferation. According to the preliminary studies on inhibitory activities, some of the newly prepared compounds indicated significantly inhibition activities against human hepatoma cancer (HepG2), human lung cancer (A549), human melanoma (A875) cell lines compared with the control 5-fluorouracil. Especially, compounds Ii (IC50 < 14 µM) and Ik (IC50 < 13 µM) exhibited obvious inhibition activities against all tested cell lines. The highly potential compound Ik induced apoptosis in HepG2 cells were analyzed by flow cytometry, and the apoptotic effects of compound Ik were further evaluated using Annexin V-FITC/propidium iodide dual staining assay, which revealed these highly potential compounds induced cell death in HepG2 cells at least partly by apoptosis.

Synthesis of 3α-deuterated 7α-hydroxy-DHEA and 7-oxo-DHEA and application in LC-MS/MS plasma analysis.

7-Oxygenated metabolites of dehydroepiandrosterone (DHEA) are known for their neuroprotective and immunomodulatory properties. These neuroactive steroids are currently predominately analysed by mass spectrometry, for which the use of internal deuterated standards is necessary. The aim of this study was to synthesize the deuterated derivatives of 7α-hydroxy-DHEA and 7-oxo-DHEA and test them in liquid chromatography-tandem mass spectrometry (LC-MS/MS) in order to enhance the performance characteristics of this method. Here we report the synthesis of 3α deuterium-labelled 7α-hydroxy-DHEA and 7-oxo-DHEA. Deuterium was introduced into the 3α position by reduction of the corresponding 3-ketone with a protected 17-carbonyl group using NaBD4. Our new procedure allows the easier synthesis of deuterated steroid labelled compounds. The use of these deuterated steroids enabled us to improve the human plasma LC-MS/MS analysis of 7α-hydroxy-DHEA and 7-oxo-DHEA in terms of sensitivity, precision and recovery.

Novel dehydroepiandrosterone benzimidazolyl derivatives as 5α-reductase isozymes inhibitors.

5α-R isozymes (types 1 and 2) play an important role in prostate gland development because they are responsible for intraprostatic dihydrotestosterone (DHT) levels when the physiological serum testosterone (T) concentration is low. In this study, we synthesized seven novel dehydroepiandrosterone derivatives with benzimidazol moiety at C-17, and determined their effect on the activity of 5α-reductase types 1 and 2. The derivatives with an aliphatic ester at C-3 of the dehydroepiandrosterone scaffold induced specific inhibition of 5α-R1 activity, whereas those with a cycloaliphatic ester (cyclopropyl, cyclobutyl, or cyclopentyl ring) or an alcohol group at C-3 inhibited the activity of both isozymes. Derivatives with a cyclohexyl or cycloheptyl ester at C-3 showed no inhibitory activity. In pharmacological experiments, derivatives with esters having an alcohol or the aliphatic group or one of the three smaller cycloaliphatic rings at C-3 decreased the diameter of male hamster flank organs, with the cyclobutyl and cyclopentyl esters exhibiting higher effect. With exception of the cyclobutyl and cyclopentyl esters, these compounds reduced the weight of the prostate and seminal vesicles.

Synthesis of Denosomin-Vitamin D3 Hybrids and Evaluation of Their Anti-Alzheimer's Disease Activities.

As an extension of previously conducted studies on developing an anti-Alzheimer's disease agent, denosomin (1-deoxy-24-norsominone, an artificial inducer of neurite elongation), derivatives were designed and synthesized based on the hypothesis that our denosomin would exhibit axonal extension activity via a 1,25D(3)-membrane-associated, rapid response steroid-binding protein (1,25D(3)-MARRS) pathway. The biological assay revealed that the hybridization of characteristic δ-lactone in denosomin and the triene moiety in VD(3) was effective to enhance the nerve re-extension activity in amyloid ß (Aß)-damaged neurons.

Cytotoxic effect of novel dehydroepiandrosterone derivatives on different cancer cell lines.

The aim of this study was to determine the cytotoxic effect of human cancer cells on three series of novel dehydroepiandrosterone derivatives containing triazole or pyrazole rings at C-17 and an ester moiety at C-3 of the androstane skeleton. The panel cancer cells used in this study were the following: PC-3, MCF-7 and SKLU-1. The results from this study indicated that the steroidal derivatives 4a-4e and 4f-4k showed the highest cytotoxic potency. This difference in this activity could be attributed to the ability of the triazole (three nitrogen atoms) to form stronger hydrogen bonds with the active site of the cell as compared to the pyrazole group having two nitrogen atoms. Compounds 4f-4k having an aromatic ester at C-3 showed an enhanced cytotoxic activity as compared to their aliphatic counterparts 4a-4e. Apparently the electronegative phenyl ring increased the polarity of the molecule, thus increasing the dipole-dipole association of the steroidal molecule with the reactive site of the cell.

Design and synthesis of novel D-ring fused steroidal heterocycles.

Using dehydroepiandrosterone as the starting material, we have synthesized a series of steroid analogs possessing a D-ring fused with heterocycles which are pyridine, imidazo [2,1-b]thiazoles or substituted thiazole imines. All the final structures are first reported and identified by NMR and MS spectroscopys, the yields of these products are moderate to good and the reaction conditions are mild. The cytotoxicity of the synthesized compounds against EC-109(human esophageal carcinoma), EC-9706(human esophageal carcinoma), MGC-803(human gastric carcinoma) were investigated.

Synthesis of novel steroid derivatives derived from dehydroepiandrosterone as potential anticancer agents.

A series of dehydroepiandrosterone derivatives containing dihydrazone unit was synthesized via a convenient condensation procedure, and which were evaluated for their potential anticancer activities. The preliminary assays indicated that some of the newly synthesized compounds exhibited good antitumor activities against human hepatocellular liver carcinoma (HepG2), heptoma (Huh-7), gastric cancer (BGC-823) and breast adenocarcinoma (MCF-7) cell lines compared with 5-fluorouracil (5-FU), which might be considered as promising lead scaffold for further design and synthesis of potential anticancer agents.

Recoverable Pd/C catalyst mediated dehydrogenation of sterols and an improved synthesis of 1α-hydroxydehydroepiandrosterone.

A novel recyclable Pd/C catalyst mediated dehydrogenation of sterols is developed. The conversion of sterols to 1,4,6-trien-3-ones is best achieved with Pd/C as a catalyst (10%) in the presence of six equivalents of allyl diethyl phosphate (ADP) and excess amount of sodium carbonate in DMF under vigorous reflux conditions. This transformation gives 17,17-ethylenedioxyandrost-1,4,6-trien-3-one in better yield than that of DDQ oxidation and thus provides an improved synthesis of 1α-hydroxydehydroepiandrosterone from DHEA.

Synthesis and antitumor activity of dehydroepiandrosterone derivatives on Es-2, A549, and HepG2 cells in vitro.

A series of dehydroepiandrosterone derivatives containing an acid ester was synthesized and evaluated for their antitumor activity on ES-2, A549, and HepG2 cells by the MTT assay. Most compounds showed antitumor activity, while compounds 1c, 2i, and 2o exhibited more potential inhibitory effects compared with dehydroepiandrosterone on ES-2 cells, A549 cells, and HepG2 cells, respectively.

Photo-DHEA--a functional photoreactive dehydroepiandrosterone (DHEA) analog.

The steroid hormone dehydroepiandrosterone (DHEA) has beneficial effects on vascular function, survival of neurons, and fatty acid metabolism. However, a specific receptor for DHEA has not been identified to date. Here, we describe the synthesis of a photoreactive DHEA derivative (Photo-DHEA). In Photo-DHEA, typical characteristics of DHEA are conserved: (i) a "planar" tetracyclic ring system with a Δ(5) double bond, (ii) a 3ß-hydroxyl group, and (iii) a keto group at C17. In cell-based assays, Photo-DHEA showed the same properties as DHEA. We conclude that Photo-DHEA is suitable for radioiodination to yield a tool for the identification of the elusive DHEA receptor.

Synthesis of dehydroepiandrosterone analogues modified with phosphatidic acid moiety.

Dehydroepiandrosterone (DHEA) and its metabolite 7α-OH DHEA have many diverse physiological, biological and biochemical effects encompassing various cell types, tissues and organs. In in vitro studies, DHEA analogues have myriad biological actions, but in vivo, especially in oral administration, DHEA produces far more limited clinical effects. One of the possible solutions of this problem is conversion of DHEA to active analogues and/or its transformation into prodrug form. In this article, the studies on the conversion of DHEA and 7α-OH DHEA into their phosphatides by the phosphodiester approach are described. In this esterification, N,N-dicyclohexylcarbodiimide (DCC) was the most efficient coupling agent as well as p-toluenesulphonyl chloride (TsCl).

Synthesis and neuromuscular blocking activity of 16-(2- and 3-pyridylmethylene) dehydroepiandrosterone derivatives.

The interonium distance plays a major role in neuromuscular blocking activity of bis-quaternary ammonium compounds. In this study we tried to alter the distance between two quaternary nitrogens in some of the steroidal derivatives synthesized and evaluated them for neuromuscular blocking activity using in vivo (in chicks) and in vitro models (rectus abdominus and chick biventer cervis muscle) for their mechanism of action. All the synthesized compounds have shown to possess good depolarizing, competitive neuromuscular blocking activity, particularly the 17-acetoxy derivative and the increase in the distance between two quaternary nitrogens decreased the activity.

Synthesis and application of a photoaffinity analog of dehydroepiandrosterone (DHEA).

We have synthesized an analog of dehydroepiandrosterone (DHEA, 1) containing both a benzophenone (BP) and a biotin (Bt) group (DHEA-BP-Bt, 8). Compound 8 was prepared by functionalization on C-17 of 1. Biocytin was reacted with 4-benzoylbenzoic acid and the product was condensed with 1 containing a diamine-hexane linker. We detected specific protein bands of approximately 55, 80, and 150 kDa by SDS-PAGE analysis of vascular endothelial cell plasma membranes which had been photoirradiated in the presence of 8.

Novel dehydroepiandrosterone derivatives with antiapoptotic, neuroprotective activity.

DHEA analogues with modifications at positions C3 or C17 were synthesized and evaluated for neuroprotective activity against the neural-crest-derived PC12 cell model of serum deprivation-induced apoptosis. The most potent compounds were the spiro-epoxy derivatives 17beta-spiro[5-androstene-17,2'-oxiran]-3beta-ol (20), (20S)-3beta,21-dihydroxy-17beta,20-epoxy-5-pregnene (23), and (20R)-3beta,21-dihydroxy-17alpha,20-epoxy-5-pregnene (27) with IC(50) values of 0.19 +/- 0.01, 99.0 +/- 4.6, and 6.4 +/- 0.3 nM, respectively. Analogues 20, 23, and 27, up to the micromolar range of concentrations, were unable to activate estrogen receptor alpha and beta (ERalpha and ERbeta) or to interfere with ER-dependent gene expression significantly. In addition, they were unable to stimulate the growth of Ishikawa, MCF-7, and LNCaP cells. Our results suggest that the spiro-epoxyneurosteroid derivatives 20, 23, and 27 may prove to be lead molecules for the synthesis of novel neuroprotective agents.

Synthesis of sominone and its derivatives based on an RCM strategy: discovery of a novel anti-Alzheimer's disease medicine candidate "denosomin".

Synthesis of sominone was achieved starting from dehydroepiandrosterone on the basis of an RCM strategy for the construction of a delta-lactone side chain. This synthetic protocol was applied for the synthesis of several analogous derivatives including 1-deoxy-24-norsominone (denosomin), which was revealed to exhibit notable bioactivities for new antidementia chemotherapy, exceeding the original natural compound sominone.

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.