Steroid Analogs Research Articles

Design, synthesis, antiproliferative activity, estrogen receptors binding affinity of C-3 pregnenolone-dihydropyrimidine derivatives for the treatment of breast cancer

Breast cancer (BCa) is very common malignancy and globally, has become the second leading cause of cancer death among women. For the treatment of BCa, estrogen receptors-alpha (ERα) has proven to be a therapeutic target. In continuation of our previous reported dihydropyrimidine-based pregnenolone derivatives, we modified at C-3 hydroxyl group. Structural architecture of estrogen receptors (ER) with excellent ER binding affinity was used for modification. MTT assay was used to evaluate the synthesized steroidal analogs for their antiproliferative activities against ER-positive MCF-7, ER-negative MDA-MB-231 (ER-) breast cancer cells and non-cancerous HEK-293 cells. Structure activity relationship (SAR) studies revealed that diethanolamine containing pregnenolone derivatives showed significant cytotoxicity against ER + MCF-7 and also showed good binding affinity with ERα and are relatively safe against HEK-293 cell model. Docking studies demonstrated that high binding affinity of diethanolamine analogs is due to their binding interaction with key amino acid residues present in the binding site of Erα.

Investigation of the Potential of Bile Acid Methyl Esters as Inhibitors of Aldo-keto Reductase 1C2: Insight from Molecular Docking, Virtual Screening, Experimental Assays and Molecular Dynamics.

Human aldo-keto reductase 1C isoforms (AKR1C1-C4) catalyze reduction of endogenous and exogenous compounds, including therapeutic drugs, and are associated with chemotherapy resistance. AKR1C2 is involved in metastatic processes and is a target for the treatment of various cancers. Here we used molecular docking to explore the potential of a series of eleven bile acid methyl esters as AKR1C2 inhibitors. Autodock 4.2 ranked 10 of the 11 test compounds above a decoy set generated based on ursodeoxycholic acid, a known AKR1C2 inhibitor, while 5 of these 10 ranked above 94 % of decoys in Autodock Vina. Seven inactives reported in the literature not to inhibit AKR1C2 ranked below the decoy threshold: 5 of these are specific inhibitors of AKR1C3, a related isoform. Using the same parameters, Autodock Vina identified steroidal analogs of AKR1C substrates, bile acids, and AKR1C inhibitors in the top 5 % of a virtual screen of a natural product library. In experimental assays, 6 out of 11 of the tested bile acid methyl esters inhibited >50 % of AKR1C2 activity, while 2 compounds were strong AKR1C3 inhibitors. Potential off-target interactions with the glucocorticoid receptor were measured using a yeast-based fluorescence assay, where results suggest that the methyl ester could interfere with binding. The top ranking compound based on docking and experimental results showed dose-dependent inhibition of AKR1C2 with an IC50 of ∼3.6 μM. Molecular dynamics simulations (20 ns) were used to explore potential interactions between a bile acid methyl ester and residues in the AKR1C2 active site. Our molecular docking results identify AKR1C2 as a target for bile acid methyl esters, which combined with virtual screening results could provide new directions for researchers interested in synthesis of AKR1C inhibitors.

General Anesthesia and the Young Brain: The Importance of Novel Strategies with Alternate Mechanisms of Action.

Over the past three decades, we have been grappling with rapidly accumulating evidence that general anesthetics (GAs) may not be as innocuous for the young brain as we previously believed. The growing realization comes from hundreds of animal studies in numerous species, from nematodes to higher mammals. These studies argue that early exposure to commonly used GAs causes widespread apoptotic neurodegeneration in brain regions critical to cognition and socio-emotional development, kills a substantial number of neurons in the young brain, and, importantly, results in lasting disturbances in neuronal synaptic communication within the remaining neuronal networks. Notably, these outcomes are often associated with long-term impairments in multiple cognitive-affective domains. Not only do preclinical studies clearly demonstrate GA-induced neurotoxicity when the exposures occur in early life, but there is a growing body of clinical literature reporting similar cognitive-affective abnormalities in young children who require GAs. The need to consider alternative GAs led us to focus on synthetic neuroactive steroid analogues that have emerged as effective hypnotics, and analgesics that are apparently devoid of neurotoxic effects and long-term cognitive impairments. This would suggest that certain steroid analogues with different cellular targets and mechanisms of action may be safe alternatives to currently used GAs. Herein we summarize our current knowledge of neuroactive steroids as promising novel GAs.

Allopregnanolone Mediates Affective Switching Through Modulation of Oscillatory States in the Basolateral Amygdala

BackgroundBrexanolone (allopregnanolone) was recently approved by the Food and Drug Administration for the treatment of postpartum depression, demonstrating long-lasting antidepressant effects. Despite our understanding of the mechanism of action of neurosteroids as positive allosteric modulators of GABAA (gamma-aminobutyric acid A) receptors, we still do not fully understand how allopregnanolone exerts persistent antidepressant effects. MethodsWe used electroencephalogram recordings in rats and humans along with local field potential, functional magnetic resonance imaging, and behavioral tests in mice to assess the impact of neurosteroids on network states in brain regions implicated in mood and used optogenetic manipulations to directly examine their relationship to behavioral states. ResultsWe demonstrated that allopregnanolone and synthetic neuroactive steroid analogs with molecular pharmacology similar to allopregnanolone (SGE-516 [tool compound] and zuranolone [SAGE-217, investigational compound]) modulate oscillations across species. We further demonstrated a critical role for interneurons in generating oscillations in the basolateral amygdala (BLA) and a role for δ-containing GABAA receptors in mediating the ability of neurosteroids to modulate network and behavioral states. Allopregnanolone in the BLA enhances BLA high theta oscillations (6–12 Hz) through δ-containing GABAA receptors, a mechanism distinct from other GABAA positive allosteric modulators, such as benzodiazepines, and alters behavioral states. Treatment with the allopregnanolone analog SGE-516 protects mice from chronic stress–induced disruption of network and behavioral states, which is correlated with the modulation of theta oscillations in the BLA. Optogenetic manipulation of the network state influences the behavioral state after chronic unpredictable stress. ConclusionsOur findings demonstrate a novel molecular and cellular mechanism mediating the well-established anxiolytic and antidepressant effects of neuroactive steroids.

Synthesis, Aromatase Inhibitory, Antiproliferative and Molecular Modeling Studies of Functionally Diverse D-Ring Pregnenolone Pyrazoles

Aromatase, a cytochrome P450 hemoprotein that is responsible for estrogen biosynthesis by conversion of androgens into estrogens, has been an attractive target in the treatment of hormonedependent breast cancer. Design of new steroidal aromatase inhibitors becomes imperative. Synthesis and biological evaluation of two classes of structurally and functionally diverse D-ring pregnenolone pyrazoles as type I aromatase inhibitors and antiproliferative agents. Pregnenolone (1) was converted to 3β-hydroxy-21-hydroxymethylidenepregn-5-en-20-one (2), which upon cyclization with phenylhydrazine generated regioisomeric pairs of pyrazoles 4 and 5. Further, Knoevenagel condensation of pregnenolone (1) with 3-oxo-3-phenylpropanenitrile (6) produced 2-benzoyl-3-(3b-hydroxyandrostan- 5-ene-20-ylidene)-but-2-enenitrile (7), which upon cyclization with hydrazine or phenylhydrazine generated the pyrazoles 8 and 9. All new steroidal derivatives were tested for their aromatase inhibition activity using Dibenzylfluorescein (DBF) based fluorescence assay developed by Stresser et al. Antiproliferative activities were measured using Sulforhodamine B assay. The activities were promising and there was a coherence between aromatase inhibitory and antiproliferative activities. The study reveals the immense potential of pregnenolone pyrazoles as aromatase inhibitors for the treatment of breast cancer. Molecular docking studies proved efficient binding of the new steroidal analogs on human placental aromatase. In the overall study, most of the compounds exhibited potential activity for the treatment of hormone dependent breast cancer. Compounds 4c and 4d were found to be the most promising pharmacons. Furthermore, compounds 4c and 4d were applied for their molecular docking study on human placental aromatase to predict their possible binding modes with the enzyme. These studies revealed that such molecules have high scope and potential for further investigation towards the treatment of estrogen dependent breast cancer.

Data-Driven Ensemble Docking to Map Molecular Interactions of Steroid Analogs with Hepatic Organic Anion Transporting Polypeptides.

Hepatic organic anion transporting polypeptides—OATP1B1, OATP1B3, and OATP2B1—are expressed at the basolateral membrane of hepatocytes, being responsible for the uptake of a wide range of natural substrates and structurally unrelated pharmaceuticals. Impaired function of hepatic OATPs has been linked to clinically relevant drug–drug interactions leading to altered pharmacokinetics of administered drugs. Therefore, understanding the commonalities and differences across the three transporters represents useful knowledge to guide the drug discovery process at an early stage. Unfortunately, such efforts remain challenging because of the lack of experimentally resolved protein structures for any member of the OATP family. In this study, we established a rigorous computational protocol to generate and validate structural models for hepatic OATPs. The multistep procedure is based on the systematic exploration of available protein structures with shared protein folding using normal-mode analysis, the calculation of multiple template backbones from elastic network models, the utilization of multiple template conformations to generate OATP structural models with various degrees of conformational flexibility, and the prioritization of models on the basis of enrichment docking. We employed the resulting OATP models of OATP1B1, OATP1B3, and OATP2B1 to elucidate binding modes of steroid analogs in the three transporters. Steroid conjugates have been recognized as endogenous substrates of these transporters. Thus, investigating this data set delivers insights into mechanisms of substrate recognition. In silico predictions were complemented with in vitro studies measuring the bioactivity of a compound set on OATP expressing cell lines. Important structural determinants conferring shared and distinct binding patterns of steroid analogs in the three transporters have been identified. Overall, this comparative study provides novel insights into hepatic OATP-ligand interactions and selectivity. Furthermore, the integrative computational workflow for structure-based modeling can be leveraged for other pharmaceutical targets of interest.

Mifepristone (Korlym ®) Use Interferes With Accurate Serum Measurement of Sex Steroids

Introduction: Mifepristone (MFP) aka RU-486/Korlym is a synthetic steroid analog originally developed in 1980 as an abortifacient that is now used in the management of Cushing’s syndrome (CS). It is both a progesterone (PG) and glucocorticoid (GC) receptor blocker. CS is often associated with reproductive functional anomalies including hypogonadism, menstrual irregularities and infertility. Due to its mode of action, measurement of serum PG and/or cortisol in patients on MFP are inaccurate indices of systemic PG and/or GC deficiency or excess. However, the potential impact of MFP use on other serum steroid assays has not been widely studied. We report the case of a 55 yr old man on treatment with MFP for adrenal CS found to have striking artefactual changes in serum androgen and estrogen levels. Case Summary: A 55 yr old African American man was referred with poorly controlled type 2 diabetes, hypertension, hyperlipidemia, obesity and untreated hypogonadism. He had a 3.2cm left adrenal incidentaloma associated with adrenal CS and he chose medical management rather than surgery. Upon starting MFP at 300mg QD serum total estrogen (by radio-immunoassay; RIA) and estradiol (by chemiluminescence immunoassay; CIA) were markedly elevated while serum total, free, bioavailable testosterone and dihydrotestosterone were all markedly reduced. His HBA1c, weight and energy levels improved on MFP despite these findings. The serum steroid levels normalized to pre-treatment levels after stopping MFP for ~ 4weeks but the changes recurred after restarting therapy. After MFP dose escalation to 300mg BID the serum steroid levels normalized after stopping MFP for ~ 6 weeks. The artefactual low testosterone levels also occured with measurement by equilibrium dialysis but “normal accurate” results were obtained when measured by liquid chromatography-Tandem mass spectrometry (LC-TMS). He remains on MFP 300mg BID without need for androgen repletion. Discussion: With increased use of MFP for CS, indices for tracking its clinical and biochemical effects assume great importance. There are few reports of the possible effects of MFP on estrogen and testosterone serum assays despite its touted low cross reactivity with sex steroids. Our case suggests that the significance, extent and prevalence of artefactual changes on serum sex steroid assays may be underestimated and under- appreciated. Conclusions: Our case of wide disparities in serum estrogen and androgen measures in a patient on MFP indicates that caution needs to be exercised in the interpretation of such results in patients on current MFP therapy. Our clinical observations suggest depending on the dose that a wash out period of 4–6 weeks is required to ensure accurate measures. Studies to ascertain the prevalence of this artefactual effect are needed and it appears testosterone measurement by LC-TMS obviates the testosterone assay artefact.

Noninvasive detection of human dehydroepiandrosterone, progesterone and testosterone using LC-MS/MS revealed effects of birth control pills/devices and body weight on ovulatory prediction

Liquid chromatography-tandem mass spectrometry (LC-MS/MS) has been increasingly used to measure steroids in human saliva. We studied the performance of a conventional LC-MS/MS for measuring dehydroepiandrosterone (DHEA), testosterone and progesterone in human saliva. These three steroids were co-extracted by liquid-liquid extraction and derivatized. Derivatives were resolved on a C18 column and quantified using an LC-MS/MS (AB Sciex API 2000) instrument. The assay’s limits of quantification were 0.03 ng/mL for all three steroids. Inter-assay coefficients of variation were 16.6–18.8% (DHEA), 12.0–15.8% (testosterone), and 12.7–19.3% (progesterone). Assay linearity analysis showed R2 of 0.9926, 0.9750 and 0.9949 for DHEA, testosterone and progesterone, respectively. No carry-over between samplings was observed. An ion-enhancement effect of 11.6% for DHEA determination and ion-suppression effects of 13.9% and 20.7% for analysis of progesterone and testosterone, respectively, were determined. No interferences by 9 steroid analogs were detected. Spiked recoveries were 85.5% (DHEA), 86.5% (testosterone), and 92.6% (progesterone). Comparison with laboratory developed test (LDT)-LC-MS/MS methods by other New York State Department of Health certified laboratories revealed R2 = 0.9425 (DHEA, LC-MS/MS = 1.0267 LDT + 21.989), R2 = 0.9849 (testosterone, LC-MS/MS = 0.9447 LDT + 9.8037), and R2 = 0.9736 (progesterone, LC-MS/MS = 1.1196 LDT + 0.0985). Reference intervals for the 3 steroids in saliva for young males and females were estimated. Results of intra-individual salivary progesterone analysis indicated that caution should be exercised when using progesterone concentrations in predicting ovulation for females who are under treatment with birth control pills/devices or has body a weight of > 90 kg.

Steroidal Glycosides from Allium tuberosum Seeds and Their Roles in Promoting Testosterone Production of Rat Leydig Cells.

A systematic phytochemical study on the components in the seeds of Allium tuberosum was performed, leading to the isolation of 27 steroidal glycosides (SGs 1–27). The structures of SGs were identified mainly by nuclear magnetic resonance and mass spectrometries as well as the necessary chemical evidence. In the SGs, 1–10 and 22–26 are new steroidal saponin analogues. An in vitro bioassay indicates that 1, 2, 7, 8, 10, 13–15, 20, 23, and 26 display promotional roles in testosterone production of rat Leydig cells with the EC50 values of 1.0 to 4.5 μM, respectively.

Activity of Ajuga iva Extracts Against the African Cotton Leafworm Spodoptera littoralis.

Simple SummaryPest insects cause tremendous damage and losses to global agriculture, and their control relies mainly on chemical insecticides, which are greatly harmful for human health and the environment. Many Ajuga plant species have secondary metabolites such as phytoecdysteroids (analogues of insect steroid hormones—ecdysteroid) that control insect development and reproduction. In this study, the effect of ingestion of Ajuga iva phytoecdysteroid plant extract on the growth and development of the African cotton leafworm Spodoptera littoralis was carried out. Our results clearly showed the susceptibility of S. littoralis to phytoecdysteroid ingestion. Crude leaf extracts and fractionated phytoecdysteroids significantly increased mortality of first-instar S. littoralis by up to 87%. Third-instar larval weight gain decreased significantly by 52%, and crude leaf extract (250 ppm) reduced gut size, with relocation of nuclei and abnormal actin-filament organization compared to the controls. In conclusion, the use of phytoecdysteroids against pest insects is not an alternative for chemical insecticides, but they could have an important role in integrated pest management strategies for controlling S. littoralis and possibly other lepidopterans.Control of the crop pest African cotton leafworm, Spodoptera littoralis (Boisduval), by chemical insecticides has led to serious resistance problems. Ajuga plants contain phytoecdysteroids (arthropod steroid hormone analogs regulating metamorphosis) and clerodanes (diterpenoids exhibiting antifeedant activity). We analyzed these compounds in leaf extracts of the Israeli Ajuga iva L. by liquid chromatography time-of-flight mass spectrometry (LC-TOF-MS) and thin-layer chromatography (TLC), and their efficiency at reducing S. littoralis fitness. First and third instars of S. littoralis were fed castor bean leaves (Ricinus communis) smeared with an aqueous suspension of dried methanolic crude extract of A. iva phytoecdysteroids and clerodanes. Mortality, larval weight gain, relative growth rate and survival were compared to feeding on control leaves. We used ‘4’,6-diamidino-2-phenylindole (DAPI, a fluorescent stain) and phalloidin staining to localize A. iva crude leaf extract activity in the insect gut. Ajuga iva crude leaf extract (50, 100 and 250 µg/µL) significantly increased mortality of first-instar S. littoralis (36%, 70%, and 87%, respectively) compared to controls (6%). Third-instar larval weight gain decreased significantly (by 52%, 44% and 30%, respectively), as did relative growth rate (−0.05 g/g per day compared to the relevant controls), ultimately resulting in few survivors. Crude leaf extract (250 µg/µL) reduced gut size, with relocation of nuclei and abnormal actin-filament organization. Ajug iva extract has potential for alternative, environmentally safe insect-pest control.

Protocolo de evaluación y manejo de efectos adversos del tratamiento esteroideo

The use of corticosteroids is becoming more and more widespread in clinical practice. They are synthetic analogs of steroid hormones and show a mineralocorticoid and glucocorticoid effect varying in duration and intensity. Its side effects are frequent and of clinical relevance and depend on the dose and cumulative duration of the corticosteroid administered. In patients treated with corticosteroids, two aspects have to be evaluated: side effects of corticosteroids and the state of the adrenal axis. Both procedures require specific study protocols. Being the use of corticosteroids a frequent practice in clinical activity, close monitoring of the patients by expert professionals to identify both the activity of the adrenal axis and the presence of side effects is required.

Graphene Oxide Membrane Immobilized Aptamer as a Highly Selective Hormone Removal.

Three-dimensional (3D) reduced graphene oxide (rGO) modified by polyethyleneimine (PEI) was prepared and functionalized by fluorophore-labeled dexamethasone-aptamer (Flu-DEX-apt) via π–π stacking interaction. The rGO/PEI/Flu-DEX-apt was used as a selective membrane for dexamethasone hormone removal from water. The prepared rGO/PEI/Flu-DEX-apt membranes were stable, insoluble, and easily removable from liquid media. The membrane was characterized by Raman spectroscopy, scanning electron spectroscopy, and FTIR spectroscopy. The rGO/PEI/Flu-DEX-apt membrane showed high sensitivity and specificity toward the dexamethasone hormone in the presence of other steroid hormone analogs, such as progesterone, estrone, estradiol, and 19-norethindrone. The fluorescence and UV–visible spectroscopy were used to confirm the membranes performance and the quantification of hormones removal. The resulting data clearly show that the graphene oxide concentration influence the aptamers and analytes interaction (π–π stacking interaction). It was found that by varying the graphene oxide concentration yields to different porosities of rGO/PEI/Flu-DEX-apt membranes affects the adsorption recovery rate, as well as the specificity and selectivity toward the dexamethasone hormone.

Controlled release of sex steroids through osmotic pump alters brain GnRH1 and catecholaminergic system dimorphically in the catfish, Clarias gariepinus

The present study aimed to evaluate osmotic pump-mediated controlled release of estrogen in males and androgen in females to analyze the impact on gonadotropin-releasing hormone (GnRH1), catecholamines (CAs) and other associated genes in the catfish, Clarias gariepinus. During pre-spawning phase, catfish were separately implanted osmotic pumps loaded with 17β-estradiol (E2) in males and 17α-methyltestosterone (MT) in females at a dose of 10 μg/100 μl or saline (100 μl) controls into both sexes to release for 21 days and all fishes were maintained as per the duration. Further, GnRH1 expression levels were analysed in the discrete regions of brain after E2 and MT treatments in male and female catfish, respectively using qPCR which revealed that GnRH1 expression was significantly higher in E2 treated male as compared to the control. On the other hand, GnRH1 expression was lower in MT treated female when compared to the control in the discrete regions of brain. In addition, certain brain and monoaminergic system related genes showed a differential response. Catfish GnRH1 could be localized in preoptic area-hypothalamus (POA-HYP) that correlated with the expression profile in the discrete regions of catfish brain. Serum levels of sex steroids in the treated male fish indicated that the treatment of E2 could maintain and impart feminization effect even in the presence of endogenous androgen during gonadal recrudescence while such an effect was not seen in females with androgen treatment. Measurement of CAs, L-3,4-dihydroxyphenylalanine, dopamine and norepinephrine levels in the male and female brain after the controlled release of E2 and MT, respectively confirmed the modulation of neurotransmitters in the E2treated male than MT treated female fish. These results collectively suggest the severity of estrogenic over androgenic compounds to alter reproductive status even at a minimal dose by targeting CAs and GnRH1 at the level of brain of catfish. This study provides insights into the reproductive toxicity of sex steroid analogues at the level of brain GnRH1 and CA-ergic system in addition to serum T, 11-KT and E2 levels during gonadal recrudescence, which is a crucial period of gametogenesis preceding spawning.

Bungsteroid A: One Unusual C34 Pentacyclic Steroid Analogue from Zanthoxylum bungeanum Maxim.

Bungsteroid A (1), possessing an unreported carbon skeleton, was isolated from the pericarps of Zanthoxylum bungeanum Maxim. It represents the first carbon skeleton of a C34 steroid analogue featuring a unique 6/6/6/6/5-fused pentacyclic skeleton, which has been determined by spectroscopic methods, quantum-chemical 13C NMR, ECD calculations, and calculations of optical rotations. Bungsteroid A showed the antiproliferative effects against HepG2, MCF-7, and HeLa cell lines with the IC50 values of 56.3 ± 1.1, 64.2 ± 0.9, and 74.2 ± 1.3 μM, respectively.

Allopregnanolone Mediates Affective Switching Through Modulation of Oscillatory States in the Basolateral Amygdala

Brexanolone (allopregnanolone), was recently approved by FDA for the treatment of post-partum depression. Despite our understanding of neurosteroids’ role as positive allosteric modulators (PAMs) of GABAA receptors, we do not fully understand how allopregnanolone exerts these antidepressant effects. In an effort to do so, we test whether allopregnanolone can alter network states in brain regions implicated in mood. We demonstrate that synthetic neuroactive steroid analogs, SGE-516 (tool-compound) and zuranolone (SAGE-217, investigational-compound), which have similar molecular pharmacology to allopregnanolone, alter oscillations across species. Acute allopregnanolone treatment confers anxiolytic behavior and enhances basolateral amygdala (BLA) high-theta oscillations (6-12 Hz) through delta-containing GABAA receptors present on BLA parvalbumin (PV+) interneurons in mice; a mechanism distinct from other GABAA PAMs, such as benzodiazepines. Further, we show that, the BLA network ex-vivo can self-sustain oscillations under PV+ interneuron control. Our findings suggest that neuroactive steroid signaling may mediate affective switching by enhancing tonic inhibition on BLA PV+ interneurons and promote a shift in the network and behavioral state.

Small-scale analysis of phytoecdysteroids in seeds by HPLC-DAD-MS for the identification and quantification of specific analogues, dereplication and chemotaxonomy.

Phytoecdysteroids are analogues of arthropod steroids occurring in plants. They contribute to invertebrate deterrence. A wide diversity of ecdysteroids occurs in phytoecdysteroid-containing plant species, sometimes in high amounts. Ecdysteroids demonstrate potentially useful pharmaceutical actions in mammals. Establish reversed-phase high-performance liquid chromatography with tandem mass spectrometry (RP-HPLC-MS/MS) and RP-HPLC-DAD-MS (diode array detector mass spectrometry) methods for the separation, identification and quantification of ecdysteroids to screen for species containing significant amounts of 20-hydroxyecdysone (20E) and other useful ecdysteroids. Micro-extracts of seed samples (ca. 30 mg) in 50% ethanol were subjected to RP-SPE (solid-phase extraction) purification prior to analysis by RP-HPLC-MS/MS and RP-HPLC-DAD-MS. The method was initially applied to genera (Amaranthus, Centaurea, Lychnis, Ourisia, Serratula, Silene and Trollius) where high-accumulating species had been previously encountered. Seeds of 160 randomly selected species, many of which have not previously been assessed, were then analysed. HPLC-MS/MS with a short analysis time initially identifies ecdysteroid-positive extracts and quantifies 20E. The positive extracts (20 ng 20E) are then analysed by HPLC-MS/MS with a longer analysis time to identify and quantify 17 common phytoecdysteroids and, finally, HPLC-DAD-MS (0.1-0.25 μg 20E) is used to obtain UV- and MS-spectra to confirm identifications or as a basis for characterisation of partially identified or novel analogues. Lychnis coronaria, Silene fimbriata and Silene hookeri ecdysteroids are characterised for the first time and those of Cucubalus baccifer and Ipheion uniflorum are more extensively characterised. The procedure provides a rapid/sensitive method for screening small plant samples for the presence, quantification and identification of ecdysteroids. It permits ready dereplication of samples, identifying extracts containing large amounts or novel analogues.

Deconstructive Functionalization of Ketones via an LMCT-Promoted C–C Cleavage

In this issue of Chem, Zuo and coworkers report an exciting new strategy for the deconstructive functionalization of ketones. Through merging Lewis-acid-catalyzed nucleophilic 1,2-addition and ligand-to-metal charge transfer (LMCT)-promoted C–C cleavage, common strained and unstrained ketones are transformed into synthetically valuable scaffolds with high efficiency under mild conditions.

SYNTHESIS , CHARACTERIZATION AND STUDY BIOLOGICAL ACTIVITY SOME NEW DERIVATIVES AMIDE AND PYRAZOLE –PYRAZOLINE OF STEROID ANALOGS .

ABSTRACT
 The number of steroids and their derivatives possess divers pharmacological activities as drugs for the treatment of a large number of diseases so in this work was suggested prepared two series amides and pyrazoles of steroid analogs ( methyl((5-pregnant-3β,17-diol-15-yl) thio) propanoate) . Amides derivatives ( 6 - 9 ) prepared directionally after treated the steroid analogs with primary amine substituted in basic medium . Carbo hydrazide steroid derivative (10 ) was obtained by treated steroid analogs with hydrazine hydrate , this compound use as intermediate for synthesis Pyrazolin (13 ) as well as Pyrazole (14) .
 All the newly synthesized compounds have been identified by IR, 1H NMR, 13CNMR, 2D-NMR ( HMBC , HSQC ) and C.H.N Analysis

Synthesis, Characterization and Study biological activity of some New Derivatives of Steroid analogs.

The search includes a new series of hydrazide- hydrazone derivatives [12-14] as well as 1,3,4- Oxidiazole[7, 8] for steroid analog (methyl((5-pregnen-3β,17-diol-15-yl) thio) propanoate) were synthesized throw react ester group with Hydrazine Hydrate in presence DMF to obtained carbohydrazide derivative (4), then the 1,3,4-Oxodiazole are prepared by interaction Benzoic Acid substituted with steroid (4) in presence Phosphorous Oxy Chloride as catalyst. while Hydrazide-hydrazone are prepared by react the steroid (4) with aromatic aldehydes or ketone by catalyzes HOAc. Structures of all the newly synthesized compounds have been elucidated by means of IR, 1H NMR, 13CNMR,2D (HMBC, HSQC) and C.H.N Analysis.

Electrochemical SELEX Technique for the Selection of DNA Aptamers against the Small Molecule 11-Deoxycortisol.

Aptamers have received considerable attention due to their numerous advantages as biorecognition receptors. However, the tediousness and high cost of the conventional selection process of aptamers remain major challenges that limit their widespread use. To overcome these limitations, here we designed a new electrochemical SELEX platform that enables a rapid, efficient, and cost-effective enrichment method for the identification of aptamers, particularly against small molecules. The selection platform is based on the immobilization of the target analyte on gold electrodes that leads to improved selection efficiency and enables in situ monitoring of the enriched DNA using square-wave voltammetry. Compared with the conventional SELEX method, this selection protocol avoids the use of beads as a solid matrix and fluorescently labeled DNA, which is usually required for small molecules, thus offering simplified aptamer/target incubation, washing, and elution steps. Moreover, the DNA recovery can be detected by simply measuring the current of the electrodes in a ferro/ferricyanide redox couple. This would eliminate the need for fluorescence labeling, which significantly reduces the cost of the procedure. The approach was successfully applied for the selection of high-affinity aptamers that bind specifically to the small molecule 11-deoxycortisol hormone using eight rounds. One of the selected aptamers that showed a dissociation constant at the subnanomolar level was used to construct a competitive voltammetric aptasensor exhibiting high sensitivity, selectivity against other steroid analogues, and possible applicability in serum samples. Thus this SELEX approach offers great promise for a faster, simpler, and more economic aptamer identification method for various targets including small molecules for a wide variety of applications.