The Experts below are selected from a list of 1335 Experts worldwide ranked by ideXlab platform
Zomer G - One of the best experts on this subject based on the ideXlab platform.
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Synthese van deutereerde anabolica
Rijksinstituut voor Volksgezondheid en Milieu RIVM, 2012Co-Authors: Zomer GAbstract:Dit rapport beschrijft de syntheses van gedeutereerde anabolica: diethylstilbestrol-D6, Hexestrol-D4, dienestrol-D2, methyltestosteron- D3, ranol-D4, trenbolon-D2, nortestosteron-D2, en medroxyprogesteron- D3. De gebruikte routes zijn dusdanig gekozen dat het mogelijk is om meer deuterium atomen in te voeren.VHIRIV
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Synthese van immunogenen en chemiluminogene labels t.b.v. de ontwikkeling van chemiluminescentie immunoassays van kleine moleculen
Rijksinstituut voor Volksgezondheid en Milieu RIVM, 2012Co-Authors: Zomer GAbstract:Dit rapport beschrijft de synthese van immunogenen voor 19- nortestosteron (NT), 17 alfamethyltestosteron (MT), medroxyprprogesteron (MP), trenbolon (TB), zeranol (Z), diethylstilbestrol (DES), Hexestrol (HEX) en dienestrol (DE). Ook werden chemiluminogene aminobutylethylisoluminol (ABEI) conjugaten gemaakt van NT, MT, MP, TB, Z, DES, HEX, DE, testosteron (T), estradiol, progesteron, 17 alfahydroxyprogesteron, cortisol en oxasepam.VHIRIV
John A Katzenellenbogen - One of the best experts on this subject based on the ideXlab platform.
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Bivalent ligands as probes of estrogen receptor action.
The Journal of Steroid Biochemistry and Molecular Biology, 1994Co-Authors: Kathryn E. Bergmann, Benita S. Katzenellenbogen, Kathryn E. Carlson, Cynthia Harris Wooge, John A KatzenellenbogenAbstract:Abstract The estrogen receptor (ER) is a hormone-regulated transcription factor which is thought to bind to specific DNA sequences as a homodimer. In order to better understand structural requirements for dimerization and its functional role in ER action, we synthesized a series of bivalent ligands based on the non-steroidal estrogen Hexestrol. These molecular probes join two Hexestrol molecules of the erythro (E, active) configuration with either 4 or 8 carbon linkers (designated E-4-E and E-8-E series, respectively), or with longer linkers comprised of ethylene glycol units (E-eg-E series). Several other bi- and monovalent control compounds were prepared. The bivalent ligands binds to ER with a relative affinity 1–7% that of estradiol. While most of the ligands demonstrated normal monophasic displacement curves in competitive binding assays with [ 3 H]estradiol, uncharacteristic biphasic competitive binding curves were seen for some of the ligands, indicating possible structure-specific, negative site-site interaction. In ER-deficient Chinese hamster ovary (CHO) cells transfected with an expression vector encoding ER, one series of bivalent ligands (E-4-E) had little stimulatory activity and inhibited transcription stimulated by Hexestrol, as determined by a transient transfection assay using an estrogen-responsive reporter gene construct [(ERE) 2 -TATA-CAT, containing two estrogen response elements linked to a TATA promoter and the chloramphenicol acetyl transferase reporter gene]. Monovalent or control bivalent ligands failed to antagonize Hexestrol-stimulated activity and were as fully active as Hexestrol itself. Studies performed in MCF-7 human breast cancer cells, which contain endogenous ER, yielded similar bioactivity profiles for the E-4-E bivalent inhibitory ligands, showing them to be effective estrogen antagonists, when using either induction of progesterone receptor or (ERE) 2 -TATA-CAT transcriptional activation as the endpoint. The E-8-E ligand, however, acted as a partial agonist/antagonist of ERE-reporter gene transactivation and a full agonist of progesterone receptor induction in MCF-7 cells, thus showing cell- and response-specific differences in the effects of the bivalent ligand. The bivalent ligands for ER do not show enhanced potency or receptor binding affinity; however, some of them display binding properties that suggest the possibility of structure-specific negative site-site interaction, and some of them function as quite effective estrogen antagonists.
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Synthesis and NMR spectrum of [13C18]-meso-Hexestrol, a fully carbon-13 substituted ligand for NMR studies of the estrogen receptor
Magnetic Resonance in Chemistry, 1993Co-Authors: Kochanny Monica J, Torleif Härd, John A KatzenellenbogenAbstract:The estrogen receptor ligand meso-Hexestrol has been synthesized with 13C enrichment (98 at.%) at every position. 13C NMR spectra of the intermediates were obtained and 13C−13C coupling patterns analyzed. The complex 13C NMR spectrum of [13C18]-meso-Hexestrol was simplified through the use of selective 13C decoupling. Several 13C−13C coupling constants were estimated from the decoupled spectra and refined via iterative simulation. Some additional coupling constants were measured in selective one-dimensional 13C COSY spectra. Coupling constants are reported to an accuracy of ±0.4–1 Hz. This study demonstrates the feasibility of determining 13C−13C coupling constants in highly 13C−substituted compounds; such compounds are expected to be used with increased frequency in studying receptor-ligand interactions by polarization transfer methods.
Philip G. Baer - One of the best experts on this subject based on the ideXlab platform.
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Bone targeted drugs: 2. Synthesis of estrogens with hydroxyapatite affinity
Bioorganic & Medicinal Chemistry Letters, 1996Co-Authors: Timothy M Willson, Deanna T. Garrison, Nora G. Geddie, Linda B Moore, Tanya Momtahen, Brad R. Henke, Philip G. BaerAbstract:Abstract The utility of the bone targeting 4-carboxy-3-hydroxy-1,2-pyrazole heterocycle was tested by the synthesis of hybrids with the non-steroidal estrogen Hexestrol. Compounds 1 and 2 demonstrated significant hydroxyapatite affinity, while maintaining weak estrogenic activity in whole cell assays.
Danchao Chen - One of the best experts on this subject based on the ideXlab platform.
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Electrochemical fabrication of polymerized imidazole-based ionic liquid bearing pyrrole moiety for sensitive determination of Hexestrol in chicken meat
Food chemistry, 2015Co-Authors: Xuemin Chen, Danchao ChenAbstract:Abstract 1-[3-(tert-Butoxycarbonylamino)propyl]-3-[3-(N-pyrrole)propyl]imidazolium tetrafluoroborate [( t -Boc-APPPI)BF 4 ], which is a novel pyrrolyl-functionalized ionic liquid, was synthesized and characterized. Subsequently, it was electrochemically deposited onto a glassy carbon electrode surface to fabricate a polymerized ionic liquid film electrode. X-ray photoelectron spectroscopy, scanning electron microscope and electrochemical impedance spectroscopy were used to confirm the successful polymerization of ionic liquid. Voltammetric behaviors of Hexestrol at the film electrode were investigated. The oxidation peak slightly shifted towards positive potential, however, dramatically increased in peak current. Experimental conditions for Hexestrol determination were optimized. The oxidation peak current is linear with Hexestrol concentration in the range of 1.0 × 10 −8 –1.0 × 10 −5 mol L −1 . The detection limit is estimated to be 2.1 × 10 −9 mol L −1 (S/N = 3). Hexestrol in chicken meat was determined using the film electrode with good accuracy.
Timothy M Willson - One of the best experts on this subject based on the ideXlab platform.
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Bone targeted drugs: 2. Synthesis of estrogens with hydroxyapatite affinity
Bioorganic & Medicinal Chemistry Letters, 1996Co-Authors: Timothy M Willson, Deanna T. Garrison, Nora G. Geddie, Linda B Moore, Tanya Momtahen, Brad R. Henke, Philip G. BaerAbstract:Abstract The utility of the bone targeting 4-carboxy-3-hydroxy-1,2-pyrazole heterocycle was tested by the synthesis of hybrids with the non-steroidal estrogen Hexestrol. Compounds 1 and 2 demonstrated significant hydroxyapatite affinity, while maintaining weak estrogenic activity in whole cell assays.