Pregnane Derivatives Research Articles

Steroidal 21-imidazolium salt derivatives: Synthesis and anticancer activity

Nitrogen-containing steroids are known as prostate cancer therapeutics. In this work, a series of pregnane derivatives bearing an imidazolium moiety were synthesized using Δ16-20-ketones as starting material. An improved approach for the construction of the 20-keto-21-heterocycle-substituted fragment involved the rearrangement of 16,17-epoxides with HCl, followed by reaction of the formed α-chloroketone with 1-substituted imidazoles. Binding affinity analysis of the imidazolium steroids and their synthetic intermediates to human CYP17A1 showed only type I (substrate-like) interactions. The strongest affinity was observed for 16α,17α-epoxy-5α-pregnan-20-on-3β-ol (Kd = 0.66 ± 0.05 µM). The steroid derivatives have been evaluated for antitumor activity against a range of prostate cancer cells as well as against various other solid tumor and hematologic cancer cell lines. All 21-imidazolium salts were active against the hormone-dependent prostate cancer line LNCaP. The most pronounced cytotoxicity in solid tumor and hematologic cancer cell lines was observed for intermediate product, 21-chloro-5α-pregn-16-en-20-on-3β-ol. Among the imidazolium salts, the derivatives with a single bond were more cytotoxic than their unsaturated congeners.

In Vitro Antibacterial, Antioxidant, Cytotoxicity Activity, and In Silico Molecular Modelling of Compounds Isolated from Roots of Hydnora johannis.

The plant Hydnora johannis has been utilized in folk medicine. Analyzing phytochemical composition of dichloromethane/methanol (1 : 1) root part of Hydnora johannis gave oleic acid (1), caffeic acid-2-hydroxynonylester (2), catechin (3), and a pregnane derivative (4). NMR spectroscopy was used to characterize compounds 1-3, while compound 4 was identified through GC-MS analysis and literature comparison. The cytotoxicity of extracts from roots of H. johannis was conducted against MCF-7 cell lines (human breast cancer) by MTT assay. According to the cytotoxicity study, n-hexane extract exhibited a high level of toxicity with 28.9 ± 5.6% cell viability. Antibacterial activity was tested against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Streptococcus pyogen. The highest bacterial growth mean inhibition zone was measured for catechin (3) (13.72 ± 0.05 mm)) against P. aeruginosa at 0.25 mg/mL and acceptable related to standard. Antioxidant activity was studied by the DPPH assay. Based on the data from the antioxidant study, DCM/MeOH extract (70.32%) and catechin (3) showed good antioxidant activity (65.61%) (IC50 0.25 μg/mL) relative to that of the positive control (78.21%, IC50 0.014 μg/mL) at 12.5 μg/mL. In each docking pose, catechin (3) scored higher binding affinity of -7.9, -7.2, and -6.4 kcal/mol towards PqsA, DNA gyraseB, and S. aureus PK, respectively, compared to amoxicillin (-8.1, -6.1, and -6.4 kcal/mol). All five Lipinski rules were obeyed by compounds 1-3, which showed an acceptable drug resemblance. The lipophilicity was computed as less than five (1.47-4.01) indicating a lipophilic property. Catechin (3) obeys Veber's rule implying its good oral bioavailability. Binding affinity scores of catechin (3)-protein interactions are in line with those from in vitro tests, indicating its potential antibacterial effect. The obtained cytotoxicity and antibacterial activity results support the utilization of H. johannis in folk medicine.

In Silico Pharmacokinetics Properties and In Vitro Bioactivities of Pregnane Derivatives and Other Compounds From Stems of Caralluma speciosa

Objectives Caralluma speciosa (N.E. Br.) N.E. Br. (Asclepiadaceae) and other succulent plants of the genus Caralluma have mainly been known for their appetite suppressing and weight loss properties, due to the presence of pregnane compounds. This study aimed to investigate chemical constituents and evaluate antimicrobial and antioxidant activities of stems of C speciosa. Methods The chloroform and methanol stems extracts were subjected to silica gel chromatographic separation. The structures of isolated compounds were established by FT-IR, 1D-NMR, and GC-MS instruments, and in comparison with reported data. The antimicrobial and antioxidant activities were performed using agar disc diffusion and DPPH assaying methods. Results The phytochemical investigation afforded 5 compounds, 3 pregnane derivatives (3-5), and 2 other compounds, heptacos-1-ene (1) and di-(2-ethylhexyl) phthalate (2). The chloroform: methanol (1:1) extract showed a good antifungal activity against Candida albicans up to 25 mg/mL dose (9.00 ± 1.00 mm to 17.17 ± 1.04 mm), equivalent to ketoconazole standard (17.67 ± 2.52 mm at 0.01 mg/disc). Compounds 3 and 5 were found violated 3 of the Lipinski's rule of 5. Compounds 2 and 4 exhibited a carcinogenicity property; while compounds 3, 4, and 5 were found as immunotoxic isolates. Conclusion All the extracts and isolated compounds 1-5 showed a negligible antibacterial and antioxidant activities compared to the antibiotic chloramphenicol (7.3 ± 0.4 to 21.15 ± 0.5 mm) and antioxidant ascorbic acid (IC50 value of 5.62 µg/mL). Hence, further biological activities study (including the anticancer, anti-inflammatory, and antifungal activities) would be needed on all the extracts and isolated compounds to look for better efficacy and predict the structure–activity relationship of the compounds.

Synthesis, in silico, and in vivo anti-inflammatory evaluation of 3β-cinnamoyloxy substituted pregna-4,16-diene-6,20-diones derivatives

Pregnane derivatives have been studied mainly for their 5α-reductase activity. However, the anti-inflammatory activities of such compounds are still poorly explored. In the search for new anti-inflammatory agents, seven new pregnane derivatives 6a-g, with cinnamic acid esters at C-3 were prepared and fully characterized. The anti-inflammatory activity of compounds was assessed in TPA induced mice ear model. From them, compound 6 b was the most active to reduce edema, with an ED50 of 0.017 mg/ear. Also, Molecular Docking and Molecular Dynamics studies were performed to identify a potential molecular target related to the inflammatory process. The in vivo results suggest that 6 b could be a potent anti-inflammatory compound, while in silico studies suggest its interaction with some critical enzymes in the inflammatory response.

Efficient Synthesis and Spectroscopic Characterization of Biologically Relevant Pregnane Derivatives, and its Glycoside

Objective:: In the present research article, we synthesized novel pregnane derivatives from 16- dehydropregnenolone acetate (1) obtained by the degradation of naturally occurring plant productdiosgenin. The oxime esters, 3β-acetoxy-pregn-5,16-diene, 20-one O-(2-(6-methoxynaphthalene-2yl) propionyl) oxime (5) and 3β-hydroxy-pregn-5, 16-diene, 20-one O-(2-(4-isobutyl phenyl) propionyl) oxime (6) have been synthesized by reaction of 3β-acetoxy-5,16-pregnadien-20-oxime (3) with NSAIDs Ibuprofen and naproxen, respectively. Methods:: The epoxide derivative 3β-hydroxy-16α, 17α-epoxypregn-5-ene-20-one (4) was opened by BF3.Et2O and yielding product 3,16-di-hydroxy pregn-5-ene-20-one (7) and 3,16,17-tri-hydroxy pregn-5- ene-20-one (8), both the synthesized compounds underwent esterification with Ibuprofen affording 3,16- di-(2-(4-isobutyl phenyl) propionoxy) pregn-5-ene-20-one (9) and 3,16-di-(2-(4-isobutyl phenyl) propionoxy) 17-hydroxy pregn-5-ene-20-one (10), respectively. Results: A one novel pregnane glycoside 3β-[2′,3′,4′,6′-tetra-O-acetyl-β-D-glucopy-ranosyl]-Oxy-20β- hydroxy-16α-methoxy-pregn-5-ene (15) has also been synthesized from 3β, 20β-dihydroxy-16α-methoxypregn- 5-ene (12). Conclusion: After the synthesis, all the compounds have been characterized by modern spectroscopic techniques.

Secretion of glucagon-like peptide-1 induced by Cynanchum pregnane derivatives: Preliminary hypotheses regarding key structural elements

• First investigation of the GLP-1 secretagogue activity of 16 pregnane derivatives. • Otophylloside A, wilfosides C1N and C3N double GLP-1 secretion in STC-1 cells. • First attempts of structure-GLP-1 secretagogue activity relationships. • The nature of the sugar chain at C-3 and ester moiety at C-12 are key elements. In our continued efforts to explore the antidiabetic potential of pregnanes from Apocynaceae, especially from the Asclepiadoideae subfamily, sixteen derivatives 1 - 16 previously isolated from various Cynanchum species, have been evaluated for their ability to increase glucagon-like peptide-1 (GLP-1) release in a cell assay. As a result, otophylloside A ( 2 ), wilfoside C1N ( 13 ), and wilfoside C3N ( 16 ) were found to stimulate significantly the secretion of GLP-1, doubling the extracellular content of this incretin. Caudatin 3- O -β-D-glucopyranosyl-(1→4)-β-D-oleandropyranosyl-(1→4)-β-D-cymaropyranosyl-(1→4)-β-D-cymaropyranoside ( 6 ) was also bioactive, but to a lesser extent (133 % of secretion compared to control cells). This study confirms the potential of certain pregnane derivatives from subfamily Asclepiadoideae to stimulate the release of GLP-1, reduced in patients with type 2 diabetes. In addition, this study outlines some putative structure-activity relationships: the nature of the sugar chain at C-3, as well as the ester moiety at C-12 position appear to be key elements to stimulate GLP-1 secretion.

Two Novel Sesquiterpenes and A New Pregnane Derivative from the South China Sea Gorgonian Subergorgia suberosa

Two Novel Sesquiterpenes and A New Pregnane Derivative from the South China Sea Gorgonian Subergorgia suberosa

Synthesis and Evaluation of Some Novel Pregnane Derivatives as Anti-Hyperlipidemic and Anti-Oxidant Agents

In the present paper, synthesis of few novel pregnane derivatives and their evaluation as potential anti-hyperlipidemic and anti-oxidant agents has been reported. The synthesis of 3β-hydroxy- 16α-methoxy pregn-5-en-20-one (4) was achieved by reaction of 3β-hydroxy-5,16-pregnadiene-20-one (3) with KOH/MeOH under reflux. Compound 4 on treatment with succinic and phthalic anhydride afforded compound 6 and 7, respectively. The reaction of the C-20-oxime-pregnadiene (8) with 1,5- dibromohexane yielded 20-(O-6-bromo hexyl)-oximino-3β-hydroxy-pregn-5, 16-diene (9). A novel heterocyclic derivative 3β-hydroxy-androst-5-en [17,16-c]-2′-methyl-7′ bromo-3′,4′-dihydro quinoline (16) was synthesized by reaction of 3 with 3-bromoaniline. However, attempted synthesis of other heterocyclic derivatives by reaction of (3) with other halogenated amine led to Aza-Michael addition products (10-14). The synthesized compounds were also evaluated for their anti-hyperlipidemic and anti-oxidant activities. Compounds 6 and 14 were found to exhibit more lipid lowering and antioxidant activities in comparison to other compounds.

Steroidal Inhibitors of CYP17A1 as a Template For Novel Anti-Cancer Agents Development

This review deals with studies of researches of novel CYP17A1 steroidal inhibitors and relative compounds published over the last ten years. The review contains six chapters in which novel targets of well-known CYP17A1 inhibirors (abiraterone and galeterone), anti-cancer and anti-proliferative activities of them major metabolites and new synthetic analogs, and in addition another nitrogen-containing androstane and pregnane derivatives are considered. In the review 354 structures of novel steroid derivatives and them anti-cancer efficiency data are considered. Analysis of the literature data allows us to consider steroidal inhibitors of CYP17A1 as multi-target anti-cancer agents with high pharmacological potential.

A CSD CRYSTALLOGRAPHIC ANALYSIS OF SOME PREGNANE CLASS OF STEROIDS

The structural diversity of steroids as well as their surpassed biological potential qualify them as challenging targets for chemical synthesis and as lead structures for pharmacological research. A total number of thirty-three structures of pregnane derivatives were obtained from the CSD for a comparative analysis of their crystallographic structures, computation of their possible biological activities and molecular packing interaction analysis. Intra and intermolecular interactions of the type X-H…A [X=C,O, N; A=O, N, S, Cl, F] have been analysed for a better understanding of molecular packing in pregnane class of steroids and discussed on the basis of distance-angle scatter plots. Molecular conformations of all the structures have been computed on the basis of the magnitude of torsion angles present in these structures. Results presented in this paper is a part of our ongoing work on the crystallographic aspects of steroidal derivatives of different classes.

Pregnane Glycosides from Cynanchum marnierianum Stimulate GLP-1 Secretion in STC-1 Cells.

In the framework of the search for natural glucagon-like peptide-1 secretagogues, the bioassay-guided fractionation of the ethanolic extract from Cynanchum marnierianum led to the isolation of two new pregnane glycosides named marnieranosides A (1) and B (2). The structures were determined based on spectroscopic data and were established as 12β,20 S-O-dibenzoyl-pregn-6-en-5α,8β,14β,17β-tetraol-3-O-β-D-oleandropyranosyl-(1 → 4)-β-D-cymaropyranoside (1) and 12β,20R-O-dibenzoyl-pregn-6-en-5α,8β,14β-triol-3-O-β-D-oleandropyranosyl-(1 → 4)-β-D-canaropyranosyl-(1 → 4)-β-D-cymaropyranoside (2). They present structural analogies to pregnanes previously described in species known for their appetite suppressant and antihyperglycemic effects, such as P57 from Hoodia gordonii. Lupeol (3), a known dipeptidyl peptidase-4 inhibitor, and the insulinomimetic kaempferol-3-O-neohesperidoside (4) were also identified in C. marnierianum. In an in vitro assay on secretin tumor cell line-1 cells, compounds 1, 2, and P57 were found to stimulate the secretion of GLP-1 by 130 % (all tested at 100 µM). These results suggest that C. marnierianum could be of great interest in the treatment of type 2 diabetes, and that pregnane derivatives should be partly responsible via the stimulation of glucagon-like peptide-1 secretion.

Synthesis and biological activity of two pregnane derivatives with a triazole or imidazole ring at C-21

Pregnane derivatives are studied as agents for the treatment of different hormone-dependent diseases. The biological importance of these steroids is based on their potential use against cancer. In this study, we report the synthesis, characterization and biological activity of two pregnane derivatives with a triazole (3β-hydroxy-21-(1H-1,2,4-triazol-1-yl)pregna-5,16-dien-20-one; T–OH) or imidazole (3β-hydroxy-21-(1H-imidazol-1-yl)pregna-5,16-dien-20-one; I–OH) moieties at C-21. These derivatives were synthesized from 16-dehydropregnenolone acetate. The activity on cell proliferation of the compounds was measured on three human cancer cells lines: prostate cancer (PC-3), breast cancer (MCF7) and lung cancer (SK-LU-1). The cytotoxic and antiproliferative effects of T–OH and I–OH were assessed by using SBR and XTT methods, respectively. The gene expressions were evaluated by real time PCR. In addition, results were complemented by docking studies and transactivation assays using an expression vector to progesterone and androgen receptor.Results show that the two compounds inhibited the three cell lines proliferation in a dose-dependent manner. Compound I–OH downregulated the gene expression of the cyclins D1 and E1 in PC-3 and MFC7 cells; however, effect upon Ki-67, EAG1, BIM or survivin genes was not observed. Docking studies show poor interaction with the steroid receptors. Nevertheless, the transactivation assays show a weak antagonist effect of I–OH on progesterone receptor but not androgenic or antiandrogenic actions.In conclusion, the synthesized compounds inhibited cell proliferation as well as genes key to cell cycle of PC-3 and MCF7 cell lines. Therefore, these compounds could be considered a good starting point for the development of novel therapeutic alternatives to treat cancer.

Preferential Inhibition of Tonically over Phasically Activated NMDA Receptors by Pregnane Derivatives.

Synaptic activation of N-methyl-d-aspartate receptors (NMDARs) plays a key role in synaptic plasticity, but excessive tonic NMDAR activation mediates excitotoxicity associated with many neurological disorders. Therefore, there is much interest in pharmacological agents capable of selectively blocking tonically activated NMDARs while leaving synaptically activated NMDARs intact. Here, we show that an endogenous neurosteroid pregnanolone sulfate is more potent at inhibiting tonically than synaptically activated NMDARs. Further, we report that a novel synthetic analog of pregnanolone sulfate, pregnanolone hemipimelate, inhibits tonic NMDAR currents without inhibiting the NMDAR component of the EPSC and shows neuroprotective activity in vivo without inducing psychomimetic side effects. These results suggest steroids may have a clinical advantage over other known classes of NMDAR inhibitors.

LC ESI-MS and FT-IR Analysis of Dendrophthoe pentandra L. Miq Leaf Methanolic Extracts to Identify Compounds with Progesterone-Like Effects

An earlier study found that progesterone hormone levels in adult female rats increased by nearly two-fold relative to usual levels following intramuscular injection (w/v, 100 mg/kg body weight for four days (s.d.d.)) of methanol extracts of Dendrophthoe petandra L. Miq (common name Benalu duku) leaves. This result suggests that Benalu duku contains pregnane derivative steroids that have carbon bonding at positions 1 and 21. Here we examined the specificity and pharmacodynamics of active substances with progesterone-like effects in crude methanol extracts made from Benalu duku leaves. Pulverized Benalu duku leaves (400 g) were extracted with 2 L analytical grade methanol at 20°C for 72 h using a shaker maceration method. The semi-solid crude extract was dried under vacuum and exposed to UV light prior to spectroscopic analysis. FT-IR and LC ESI MS analysis detected active substances having a pregnane derivative chemical structure with progesterone, medroxy progesterone acetate, megestrol acetate and dydrogesterone present at distributions of about 30, 66, 3 and 1% Key words : benalu duku, pregnane derivate, anabolic steroid, leaf extract FT-IR Methanolic leaf extract LC- ESI MS

Synthesis, crystal structure, conformational analysis, nonlinear optical property and computational study of novel pregnane derivatives

The molecular structure and detailed spectroscopic analysis of some novel newly synthesized pregnane derivatives have been performed using experimental techniques like 1H, 13C NMR, NOESY, FT-IR, UV–visible spectroscopy, mass spectrometry, crystallography, as well as theoretical calculations. The structure and stereochemistry of 3β-benzoyloxy 16α-methoxy pregn-5-ene-20-one (3) has been confirmed by single crystal X-ray diffraction, which crystallized in orthorhombic form having P212121 space group with unit cell parameters a=6.395(5)Å, b=19.872(17)Å, c=19.898(16)Å and Z=4. Quantum chemical calculations have been performed by density functional theory (DFT) using B3LYP functional and 6-31G (d,p) basis set. The electronic properties such as frontier orbitals and band gap energies have been calculated using time dependent density functional theory (TD-DFT). The strength and nature of weak intramolecular interactions have been studied by AIM approach. The vibrational wavenumbers have been calculated using DFT method and assigned with the help of potential energy distribution (PED). Global and local reactivity descriptors have been computed to predict reactivity and reactive sites in the molecule. First hyperpolarizability values have been calculated to describe the nonlinear optical (NLO) property of the synthesized compounds. Molecular electrostatic potential (MEP) analysis has also been carried out.

Disturbances in production of progesterone and their implications in plant studies

Progesterone is a mammalian hormone that has also been discovered in plants but its physiological function in plants is not explained. Experiments using inhibitors of progesterone synthesis and binding would be useful in studies on the significance of this compound in plants. Until now, trilostane and mifepristone have been used in medical sciences as progesterone biosynthesis and binding inhibitors, respectively. We tested these synthetic steroids for the first time in plants and found that they reduced the content of progesterone in wheat. The aim of further experiments was to answer whether the potential disturbances in the production/binding of progesterone, influence resistance to environmental stress (drought) and the development of wheat. Inhibitors and progesterone were applied to plants via roots in a concentration of 0.25–0.5mg/l water. Both inhibitors lowered the activity of CO2 binding enzyme (Rubisco) in wheat exposed to drought stress and trilostane additionally lowered the chlorophyll content. However, trilostane-treated plants were rescued by treatment with exogenous progesterone. The inhibitors also modulated the development of winter wheat, which indicated the significance of steroid regulators and their receptors in this process. In this study, in addition to progesterone and its inhibitors, brassinosteroid (24-epibrassinolide) and an inhibitor of biosynthesis of brassinosteroids were also applied. Mifepristone inhibited the generative development of wheat (like 24-epibrassinolide), while trilostane (like progesterone and an inhibitor of biosynthesis of brassinosteroids) stimulated the development. We propose a model of steroid-induced regulation of the development of winter wheat, where brassinosteroids act as inhibitors of generative development, while progesterone or other pregnane derivatives act as stimulators.

Conversion of Tomato Saponins to Pregnane Derivatives

Here reports new conversions methods of tomato saponins, esculeoside A (1) and a mixture of esculeosides B-1 (2) and B-2 (3), (the latter two were obtained from tomato cans) into pregnane derivative (5) by an alkal treatment followed by acid treatment. Compound 1 or a mixture of 2 and 3 were each refluxed with 1 N KOH to afford a characteristic pyridine steroidal glycoside (4), which was then treated with 2 N HCl-MeOH to afford a pregnane derivative, 3β-hydroxy-5α-pregn-16-en-20-one (5). The results of the above two reactions indicated that tomato saponins are chemically closely related to pregnane hormones. We assume that the assimilated tomato saponins via the small intestine are metabolized into pregnane derivatives, demonstrating various bioactivities such as anti-cancer, anti-osteoporosis, and anti-menopausal disorder activities.

Antifouling steroids from the South China Sea gorgonian coral Subergorgia suberosa

Two new unusual cholestane derivatives, pentacyclic steroid 16,22-epoxy-20β,23S-dihydroxycholest-1-ene-3-one (1) and 20β,23S-dihydroxycholest-1-ene-3,22-dione (2), along with two new pregnane derivatives, 15β,17α-dihydroxypregna-4,6-diene-3,20-dione (3) and 11α-hydroxypregna-4-ene-3,6,20-trione (4), were isolated from the South China Sea gorgonian coral Subergorgia suberosa. Their structures were established based on the extensive analyses of 2D NMR, IR, and HRMS. Antifouling tests against Balanus amphitrite larvae settlement indicated that 1 and 2 exhibited inhibitory effect with EC50 values of 5.3, and 14.5μg/mL, respectively.

Androstanes and pregnanes from Trichilia emetica ssp. suberosa J.J. de Wilde

Four pregnanes: 1-methoxy-pregnan-17(R)-1,4-dien-3,16-dione (1), 1-methoxy-pregnan-17(S)-1,4-dien-3,16-dione (2), 2,3-seco-pregnan-17(S)-2,3-dioic acid-16-oxo-dimethyl ester (4), 2α,3α,16α-trihydroxy-5α-pregnan-17(R)-20-yl acetate (7), three androstanes: 1-methoxy-androstan-1,4-dien-3,16-dione (3), 2,3-seco-androstan-2,3-dioic acid-16-oxo-dimethyl ester (5), 3-methoxycarbonyl-2,3-seco-androstan-3-oic acid-16-oxo-2,19-lactone (6), together with three known pregnane derivatives, were isolated from the roots of Trichilia emetica ssp. suberosa. Their structures were determined by means of 1D and 2D NMR spectroscopy, mass spectrometry analysis, as well as by quantum chemical calculations.

Proficient synthesis of biologically active pregnane derivatives and its glycoside – Experimental and theoretical approach

Synthesis of a number of pregnane derivatives including the glycoside has been described in detail. These compounds were synthesized by reaction of 3β-acetoxy-5, 16-pregnadiene-20-one, derived from diosgenin and then treating it with different nucleophilic reagents. The structures of these newly synthesized compounds were established on the basis of their physical, chemical and spectral data. The molecular geometry of compounds were calculated in ground state by density functional theory method (DFT/B3LYP) using 6-31G (d,p) basis set. 1H NMR chemical shifts were also studied using gauge-including atomic orbital (GIAO) approach, which were found in good agreement with the experimental values. The study of electronic properties such as UV–Vis spectral analysis, HOMO and LUMO energy calculations were performed with time dependent DFT (TD-DFT). Global and local reactivity descriptors were calculated to study the reactive sites within the molecules. These compounds were also evaluated for their anti-dyslipidemic (Triton model) and in vitro anti-oxidant activities. Out of these, compound 9 showed potent anti-dyslipidemic and anti-oxidant activity.