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New Steroids (new + steroid)
Selected Abstracts1H and 13C NMR assignments for two new steroids from the coral Chromonephthea sp.MAGNETIC RESONANCE IN CHEMISTRY, Issue 4 2009Hua-Wei Geng Abstract Two new steroids isolated from EtOH extracts of the South China Sea soft coral Chromonephthea sp. were identified. One-dimensional (1D) and two-dimensional (2D) NMR experiments including COSY, HSQC, HMBC and NOESY were used for the determination of their structure. Copyright © 2008 John Wiley & Sons, Ltd. [source] Structure determination of new steroids from Abutilon pakistanicum by NMR techniquesMAGNETIC RESONANCE IN CHEMISTRY, Issue 3 2008Munawar Hussain Abstract Two new steroids provisionally named as pakisteroid-A (1) and pakisteroid-B (2) have been isolated in crystalline form from Abutilon pakistanicum. Their structures have been assigned as 3- O -,- D -glucopyranosyl-stigmasta-5,11(12)-diene (1) and 24,-ethylcholesta-5, 9(11), 22E-trien-3,-benzoate (2), respectively through extensive NMR studies. Copyright © 2008 John Wiley & Sons, Ltd. [source] Effects of two new steroids and cyproterone on some biomarkers of oxidative stress and serotonergic system on rat prostate and brainANDROLOGIA, Issue 1 2009G. D. Calderón Summary The purpose of this study was to evaluate the effect of cyproterone acetate (CPA, A) compared with new synthetic steroids 3,-acetoxy-5,6-epoxy-16-pregnen-20-one (B) and 17,-hydroxy-16,-methyl-1,4,6-pregnatriene-3,20-dione (C) in rat prostate and brain. Groups of animals were treated either with A, B or C (4 mg kg,1 day,1) by the intraperitoneal route for 5 days. Levels of reduced glutathione (GSH), 5-hydroxy-indole acetic acid (5-HIAA), lipid peroxidation (as thiobarbituric acid reactive substances, TBARS) and the activities of Na+, K+ - and total ATPases were assayed in prostate and brain for each group of animals including a control group. No appreciable changes were shown in Na+, K+ -ATPase and total ATPases and TBARS on prostate and brain of rats that received A, B and C steroids. However, the levels of GSH and 5-HIAA decreased significantly (P < 0.05) in both tissues for the steroids assayed. It is concluded that CPA and the homologues B and C steroids induce changes in the levels of GSH and serotonin in rat prostate and brain. [source] Structure,Activity Relationships in Cholapod Anion Carriers: Enhanced Transmembrane Chloride Transport through Substituent TuningCHEMISTRY - A EUROPEAN JOURNAL, Issue 31 2008Abstract Chloride transport by a series of steroid-based "cholapod" receptors/carriers was studied in vesicles. The principal method involved preincorporation of the cholapods in the vesicle membranes, and the use of lucigenin fluorescence quenching to detect inward-transported Cl,. The results showed a partial correlation between anion affinity and transport activity, in that changes at the steroidal 7 and 12 positions affected both properties in concert. However, changes at the steroidal 3-position yielded irregular effects. Among the new steroids investigated the bis- p -nitrophenylthiourea 3 showed unprecedented activity, giving measurable transport through membranes with a transporter/lipid ratio of 1:250,000 (an average of <2 transporter molecules per vesicle). Increasing transporter lipophilicity had no effect, and positively charged steroids had low activity. The p -nitrophenyl monourea 25 showed modest but significant activity. Measurements using a second method, requiring the addition of transporters to preformed vesicle suspensions, implied that transporter delivery was problematic in some cases. A series of measurements employing membranes of different thicknesses provided further evidence that the cholapods act as mobile anion carriers. [source] | ||||||||||