Ethyl Iodide (ethyl + iodide)

Distribution by Scientific Domains

Selected Abstracts

Synthesis of [1- 11C]ethyl iodide from [11C]carbon monoxide and its application in alkylation reactions

Jonas Eriksson
Abstract A method is presented for preparing [1- 11C]ethyl iodide from [11C]carbon monoxide. The method utilizes methyl iodide and [11C]carbon monoxide in a palladium-mediated carbonylation reaction to form a mixture of [1- 11C]acetic acid and [1- 11C]methyl acetate. The acetates are reduced to [1- 11C]ethanol and subsequently converted to [1- 11C]ethyl iodide. The synthesis time was 20 min and the decay-corrected radiochemical yield of [1- 11C]ethyl iodide was 55 ± 5%. The position of the label was confirmed by 13C-labelling and 13C-NMR analysis. [1- 11C]Ethyl iodide was used in two model reactions, an O -alkylation and an N -alkylation. Starting with approximately 2.5 GBq of [11C]carbon monoxide, the isolated decay-corrected radiochemical yields for the ester and the amine derivatives were 45 ± 0.5% and 25 ± 2%, respectively, based on [11C]carbon monoxide. Starting with 10 GBq of [11C]carbon monoxide, 0.55 GBq of the labelled ester was isolated within 40 min with a specific radioactivity of 36 GBq/µmol. Copyright © 2004 John Wiley & Sons, Ltd. [source]

Synthesis, Structural Evaluation, and Estrogen Receptor Interaction of 4, 5-Bis(4-hydroxyphenyl)imidazoles

Ronald Gust
Abstract 4, 5-Bis(4-hydroxyphenyl)imidazoles with 2, 2,-H (1), 2, 2,-F (2), 2, 2,-Cl (3), and 2, 2,6-Cl (4) substituents in the aromatic rings were synthesized by oxidation of the respective methoxy-substituted (R, S)/(S, R)-4, 5-diaryl-2-imidazolines with MnO2 and subsequent ether cleavage with BBr3. N -alkylation of 1 and 3 with ethyl iodide yielded the compounds 5 and 6. The imidazoles were characterized by NMR spectroscopy and tested for estrogen receptor binding in a competition experiment with [3H]estradiol using calf uterine cytosol. Gene activation was verified in a luciferase assay using estrogen receptor positive MCF-7-2a cells stably transfected with the plasmid EREwtcluc. All halide substituted imidazoles competed with estradiol for the binding site at the estrogen receptor. The N -ethyl derivative 6 showed the highest relative binding affinity of 1.26 %. Treatment of MCF-7-2a cells, however, did not lead to gene activation. The relative activation of 6 amounted only to 10 % at 1,M compared to E2 (100 %). [source]