Synthesis and biological activity of brassinosteroids fluorinated at C-2.

abstract：:The crystal and molecular structure of 3-methoxy-9(10 leads to 19)abeo-1,3,5(10)-estratrien-17-one has been determined by X-ray analysis in order to ascertain the configuration at C(9). The seven-membered B-ring has a chair conformation and this causes the molecule to bow towards the alpha-face rather than towards the...

journal_title：Steroids

authors： Weeks CM,Rohrer DC,Duax WL

更新日期：1976-02-01 00:00:00

abstract：:Estradiol (E2), progesterone (P4), and oxytocin (OT) are important for the initiation of luteolysis in ruminants but the mechanisms involved are still poorly understood. The objective of this study was to determine if duration of exposure of bovine endometrial epithelial cells to P4 affected the response of the cells ...

journal_title：Steroids

authors： Kombé A,Sirois J,Goff AK

更新日期：2003-09-01 00:00:00

abstract：:(25S)-3-Oxocholesta-1,4-dien-26-oic acid (1) and a new (25S)-18-acetoxy-3-oxocholesta-1,4-dien-26-oic acid (2) were isolated from a soft coral Minabea sp. (cf. aldersladei) collected in North Sulawesi, Indonesia, together with two known cholic-acid-type compounds, 3-oxochol-1,4-dien-24-oic acid (3) and 3-oxochol-4-en-...

journal_title：Steroids

authors： Wang W,Lee JS,Nakazawa T,Ukai K,Mangindaan RE,Wewengkang DS,Rotinsulu H,Kobayashi H,Tsukamoto S,Namikoshi M

更新日期：2009-09-01 00:00:00

abstract：:The apolar ecdysteroid present in the developing embryo of the blue crab, Callinectes sapidus Rathbun, is tentatively identified as ponasterone A (2 beta, 14 alpha, 20,22-pentahydroxy-5, beta-cholest-7-en-6-one) on the basis of chromatographic, immunological, and mass spectral evidence. The apolar ecdysteroid present ...

journal_title：Steroids

authors： McCarthy JF

更新日期：1979-12-01 00:00:00

abstract：:Propargyl amine was protected by condensing it with 2,5-hexane-dione to give 2,5-dimethyl-N-(2'-propyn-1'-yl)pyrrole (2). The latter was converted to the corresponding Grignard reagent with ethylmagnesium bromide, and then condensed with estrone tetrahydropyranyl ether to give 17 alpha-[3'-(2'',5''-dimethyl-1''-pyrryl...

journal_title：Steroids

authors： Blickenstaff RT,Foster E,Gerzon K,Young P

更新日期：1986-09-01 00:00:00

abstract：:The chemoselectivity of rigid cyclic alpha,beta-unsaturated carbonyl group on the reducing agents was influenced by the ring size and steric factor. Cholesterol (cholest-5-en-3beta-ol) and dehydroepiandrosterone (DHEA) were oxidized with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone to form 1,4,6-cholestatrien-3-one and 1...

journal_title：Steroids

authors： Kim E,Ma E

更新日期：2007-04-01 00:00:00

abstract：:Optimal assay conditions for cholesterol 7 alpha-hydroxylase activity in swine liver microsomes were determined. The enzyme activity is induced three-fold by feeding cholestyramine to the swine. This suggests that cholesterol 7 alpha-hydroxylase is likely to be the rate-limiting enzyme for biosynthesis of bile acids i...

journal_title：Steroids

authors： Li JR,Kim DN

更新日期：1979-03-01 00:00:00

abstract：:Estradiol (E2) and other steroids have recently been shown to initiate various intracellular signaling cascades from the plasma membrane, including those stimulating mitogen-activated protein kinases (MAPKs), and particularly extracellular-regulated kinases (ERKs). In this study we demonstrated the ability of E2 to ac...

journal_title：Steroids

authors： Bulayeva NN,Gametchu B,Watson CS

更新日期：2004-03-01 00:00:00

abstract：:Glucocorticoids are an important class of anti-inflammatory/immunosuppressive drugs. A crucial part of their anti-inflammatory action results from their ability to repress proinflammatory transcription factors such as nuclear factor-κB (NF-κB) and activator protein-1 (AP-1) upon binding to the glucocorticoid receptor ...

journal_title：Steroids

authors： Cechin SR,Buchwald P

更新日期：2014-07-01 00:00:00

abstract：:Seventeen cholesteryl alkyl ethers were synthesized through alcoholysis of cholesterol p-toluenesulfonate. This method was found superior to the etherification of sodium or potassium cholesterylate with alkyl halides or methanesulfonates, especially for the preparation of long-chain unsaturated aklyl ethers of [7(m)-3...

journal_title：Steroids

authors： Halperin G,Gatt S

更新日期：1980-01-01 00:00:00

abstract：:There are currently two main candidates for the membrane receptor for 1,25(OH)2D3: the 1,25D3-MARRS protein/ERp57; and the classical VDR. The 1,25D3-MARRS protein is essential for hormone-stimulated phosphate and calcium uptake in chick intestinal cells, whereas the VDR is not. The 1,25D3-MARRS protein also shows a hi...

journal_title：Steroids

authors： Nemere I

更新日期：2005-05-01 00:00:00

abstract：:Carbenoxolone potentiates the mineralocorticoid activity of endogenous glucocorticoid hormones by inhibiting the enzyme 11 beta-hydroxysteroid dehydrogenase, which converts cortisol and corticosterone to inactive 11-oxo-derivatives. We addressed the question of whether glucocorticoid activity is also affected by carbe...

journal_title：Steroids

authors： Soro A,Panarelli M,Holloway CD,Fraser R,Kenyon CJ

更新日期：1997-04-01 00:00:00

abstract：:The hydrolysis of 108 esters of norethisterone (17 alpha-ethynyl-17 beta-hydroxyestr-4-en-3-one) was studied in vitro using a rabbit liver preparation. Introduction of a double or triple bond into a straight-chain ester did not inhibit hydrolysis but a marked reduction in hydrolysis was produced on replacement of a me...

journal_title：Steroids

authors： Naderi S,Fotherby K

更新日期：1983-03-01 00:00:00

abstract：:Several derivatives of the arthropod moulting hormone have been synthesized which were coupled to AH Sepharose 4B yielding about 2 mumole ligand per g wet gel. As an indication of the suitability of the ligands for biological work the puff inducing capacity of their methyl esters was tested. The methyl ester of inokos...

journal_title：Steroids

authors： Spindler KD,Hamann A,Spindler-Barth M,Ihne A,Beckers C,Emmerich H

更新日期：1976-04-01 00:00:00

abstract：:An efficient procedure for the chemical synthesis of 3 beta-hydroxy-5 alpha-cholest-8-en-7-one and 3 beta-hydroxy-5 alpha-cholest-8-en-11-one is described. These ketosterols have been shown to have possible significant hypocholesterolemic effects when fed to normal rats at a level of 0.15% in a laboratory chow diet. T...

journal_title：Steroids

authors： Parish EJ,Nanduri VB,Seikel JM,Kohl HH,Nusbaum KE

更新日期：1986-11-01 00:00:00

abstract：:In this paper, we studied the effect of heme availability on corticosterone and aldosterone synthesis in rat adrenal. We found that hemin stimulated corticosterone and aldosterone production in adrenal homogenates in a dose-dependent fashion. Hemin administration to rats also provoked an increase in both corticosteron...

journal_title：Steroids

authors： Martini CN,Vaena de Avalos SG,Romero DG,San Martín de Viale L,Vila Mde C

更新日期：1997-12-01 00:00:00

abstract：:We report the synthesis of 10 novel steroids obtained from 3 beta, 15 beta-diacetoxy-17 alpha-hydroxy-5-pregnen-20-one (1c) as intermediates in the synthesis of 15 beta-acetoxy-20,20-ethylenedioxy-17 alpha-hydroxy-4-pregnen-3-one (6a) and its tritiated tracer 15 beta-acetoxy-20,20-ethylenedioxy-17 alpha-hydroxy-1,2,6,...

journal_title：Steroids

authors： Reeder AY,Joannou GE

更新日期：1997-02-01 00:00:00

abstract：:The addition of molybdate to rabbit liver cytosol increased significantly the affinity of the glucocorticoid receptor for [3H] dexamethasone without influencing the concentration of binding sites. This effect was concentration dependent. Analysis of the binding data by curve-fitting and Scatchard plot revealed the occ...

journal_title：Steroids

authors： Blanchardie P,Lustenberger P,Orsonneau JL,Denis M,Bernard S

更新日期：1984-08-01 00:00:00

abstract：:By analyzing the steroidal content of fresh whole plants of Tacca subflabellata (Taccaceae), we isolated one sapogenin and eight glycosides with four kinds of steroidal skeletons including four new glycosides, named taccasubosides A-D (1-4), together with five known compounds. Among them, compound 1 is the first penta...

journal_title：Steroids

authors： Li L,Ni W,Li XR,Hua Y,Fang PL,Kong LM,Pan LL,Li Y,Chen CX,Liu HY

更新日期：2011-09-01 00:00:00

abstract：:Hydroxycitric acid (HCA), a dietary-derived weight loss supplement, competitively inhibits ATP citrate lyase (ACLY). Tamoxifen (TAM) is the most frequently used therapy for estrogen receptor (ER)-positive breast cancer patients, but its application was restricted due to efficacy related issues. Lipid metabolic reprogr...

journal_title：Steroids

authors： Ismail A,Doghish AS,E M Elsadek B,Salama SA,Mariee AD

更新日期：2020-08-01 00:00:00

abstract：:Significant changes in % free serum E2, T and P were observed during the annual cycle of the turtle. In contrast no significant changes in SHBG affinity constants (2.29-4.48 x 10(8) M-7) were found and binding capacity for estradiol 17B was between 3.47 and 3.96 x 10(-7) M except in preovulatory animals (2.00 +/- 0.25...

journal_title：Steroids

authors： Albert C,Callard IP

更新日期：1988-10-01 00:00:00

abstract：:A phytochemical study of Physalis pubescens L. afforded twelve compounds, including six new withanolides (1, 4, and 6i-9), four new withanolide glucosides (2, 3, 5, and 6), and two known withanolides (10 and 11). Their structures were established via extensive spectroscopic analysis. The absolute configuration of 3 wa...

journal_title：Steroids

authors： Xia G,Li Y,Sun J,Wang L,Tang X,Lin B,Kang N,Huang J,Chen L,Qiu F

更新日期：2016-11-01 00:00:00

abstract：:Many flavonoids and isoflavonoids have anti-diabetic effects in animal models. However, the mechanisms that are involved are generally unclear. Since 11β-hydroxysteroid dehydrogenases (HSD11Bs) play important roles in diabetes, we hypothesize that flavonoids and isoflavonoids may affect diabetes by targeting two isofo...

journal_title：Steroids

authors： Zhu Q,Ge F,Dong Y,Sun W,Wang Z,Shan Y,Chen R,Sun J,Ge RS

更新日期：2018-04-01 00:00:00

abstract：:The left adrenal of two female dogs were perfused with either 3 muCi [4-14C]cpd. S (2) and 45 muCi [1, 2-3H] 21-deoxycortisone (Dog I), or with 1 muCi [4-14C] 17-hydroxyprogesterone and 65 muCi [1,2-3H] 21-deoxycortisone (Dog II). In Dog I, 40% of the perfused 21-deoxycortisone was converted to cortisone and 23% of cp...

journal_title：Steroids

authors： Horn H,Halperin G,Weidenfeld J,Mordohovich D,Maschler I

更新日期：1977-08-01 00:00:00

abstract：:3 alpha-Hydroxysteroid dehydrogenase (3 alpha HSD) is one of the main enzymes involved in the metabolism of the active androgen, dihydrotestosterone (DHT). 3 alpha HSD catalyzes the reversible reduction of DHT to 5 alpha-androstane-3 alpha, 17 beta-diol (3 alpha DIOL). The equilibrium of 3 alpha HSD reductive and oxid...

journal_title：Steroids

authors： Pirog EC,Collins DC

更新日期：1994-04-01 00:00:00

abstract：:Homogeneous catalytic hydrazinocarbonylation of some steroid derivatives possessing iodo-alkenyl moiety (17-iodo-androst-16-ene 1, 17-iodo-3-methoxy-estra-1,3,5(10),16-tetraene 2, 17-iodo-4-aza-4-methyl-androst-16-en-3-one 3 and 17-iodo-6beta-hydroxy-3alpha,5alpha-cycloandrost-16-ene 4) were carried out in the presenc...

journal_title：Steroids

authors： Szarka Z,Skoda-Földes R,Horváth J,Tuba Z,Kollár L

更新日期：2002-06-01 00:00:00

abstract：:The purpose of this study was to determine the short-term effects of progesterone action on estrogen receptor (Re) levels in the rat uterus. Ovariectomized, adrenalectomized rats were maintained on subcutaneous Silastic implants containing crystalline estradiol. Progesterone treatment with serum estradiol maintenance ...

journal_title：Steroids

authors： Okulicz WC,Evans RW,Leavitt WW

更新日期：1981-04-01 00:00:00

abstract：:The urinary excretion of 3beta,16beta-dihydroxy-5-androsten-17-one (16beta-OH-DHEA) is increased in patients with low renin essential hypertension. This steroid and its isomer 3beta,17beta-dihydroxy-5-androsten-16-one (16-oxo-A) have also been reported to have mineralocorticoid activity in adrenalectomized rats. These...

journal_title：Steroids

authors： Ogihara T,Ichihara K,Yamamoto T,Kumahara Y,Kircher HW,Nugent CA

更新日期：1977-01-01 00:00:00

abstract：:Saturation analysis of the binding of [3H]dexamethasone [( 3H]DEX) to ammonium sulfate precipitates (ASPs) confirmed the presence of a limited-capacity, high-affinity binder in human adipose tissue cytosols. Various non-radioactive steroids competed with [3H]DEX for binding to the ASPs in the following sequence: dexam...

journal_title：Steroids

authors： Miller LK,Kral JG,Strain GW,Zumoff B

更新日期：1987-06-01 00:00:00

abstract：:Gonadal steroids modulate adrenal gland size and function in a variety of species, and our previous studies demonstrate that circulating androgens suppress 3beta-hydroxysteroid dehydrogenase-isomerase (3betaHSD) activity in the adrenal cortex of male mice. The present study tests the hypothesis that androgens have a d...

journal_title：Steroids

authors： Stalvey JR

更新日期：2002-07-01 00:00:00