Neue gas-chromatographische Methode zur quantitativen Bestimmung von 3α-?tiocholanolon aus dem Plasma mit dem Alkaliflammendetektor

Ohne ZusammenfassungWir sind überzeugt, die Nachweisgrenze von 3-Et aus biologischem Material weiter senken zu können.     

Vergleich von Disk-Elektrophorese und isoelektrischer Fokussierung zur Untersuchung der Metabolisierung eines Steroidpharmakons

Ohne Zusammenfassung

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A comparison of disk-electrophoresis and isoelectric focusing demonstrated in the metabolism of a steroidal drug

     

Tetrahydrothiophene-Based Ionic Liquids: Synthesis and Thermodynamic Characterizations

S-alkyltetrahydrothiophenium, [C_nTHT]⁺ bis(trifluorosulfonyl)imide, [NTf₂]⁻ room temperature ionic liquids (ILs) and tetraphenylborate, [BPh₄]⁻ salts with alkyl chain lengths from C₄ to C₁₀ have been prepared. The ILs and salts were characterized and their purity verified by ¹H- and ¹³C-nuclear magnetic resonance, elemental analysis, ion chromatography, Karl-Fischer titration, single crystal X-ray diffraction as well as thermogravimetric analysis. The experimentally determined density and viscosity decrease with increasing temperature. The experimental solubility of the [C_nTHT][NTf₂]-ILs in water (75 to 2.2 mg/L for C₄ to C₁₀) was modelled with very good agreement by Perturbed Chain Statistical Associating Fluid Theory (PC-SAFT), based on the extremely low vapor pressures for the [C_nTHT][NTf₂]-ILs measured in this work (4.15 to 0.037 ⋅ 10⁻⁷×p_sat for C₄ to C₁₀). PC-SAFT is able to predict and correlate different thermodynamic properties by estimating the Helmholtz residual energy.     

Ferrocenylmethylation of estrone and estradiol: Structure,electrochemistry, and antiproliferative activity of new ferrocene–steroid conjugates

Conjugates of ferrocene with steroidal estrogens as selective antiproliferative agents against hormone-dependent breast cancer cells are believed to be limited by the inherent estrogenicity of the conjugates. Motivated by a significant cytotoxicity of the ester of ferrocenecarboxylic acid and the phenolic group of estradiol toward such a cell line, we decided to explore other a -ring-tethered ferrocene–estra-1,3,5(10)-triene conjugates; in this study, ferrocenylmethylation of estradiol and estrone with (ferrocenylmethyl)trimethylammonium iodide in the presence of potassium carbonate yielded five new compounds ( 1 – 5 ). In dimethylformamide, only O-alkylated products formed ( 1 and 3 ), while a mixture of O- and C-alkylated products was obtained when methanol was used ( 2 , 4 , and 5 in addition to 1 and 3 ). All compounds were characterized using 1D and 2D NMR, IR, UV–Vis, and high-resolution mass spectrometry. Two of the conjugates, a 3-O- and a 4-C-alkylated derivative of estrone ( 3 and 4 , respectively), were also analyzed using single-crystal X-ray diffraction. A cyclic voltammetric investigation of the electrochemical properties of 1 – 5 was performed. While some of the compounds were shown to have a slight-to-moderate antiproliferative activity against at least one of the six tested human tumor cell lines and were nontoxic to (the noncancerous) fetal human fibroblasts, compound 2 (4-(ferrocenylmethyl)estra-1,3,5(10)-triene-3,17β-diol) with an IC₅₀ value of 0.34 μM was found to be more active against the hormone-dependent breast cancer cell line MCF-7 than doxorubicin. These results suggest that a -ring substitution of steroidal estrogens is a plausible strategy for preparing other ferrocene–steroid conjugates acting against tumor cells.     

Entwicklungsstand und Anwendung der Tr?gerelektrophorese als Mikroverfahren

Ohne Zusammenfassung     

Beeinflussung der Testosteron-Messung durch das Sexual-Hormon-bindende Globulin in Radioimmunoassays ohne Extraktion

Ohne Zusammenfassung

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Interference of sex-hormone-binding globulin in no-extraction radioimmunoassays for testosterone