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Bromo Derivative (bromo + derivative)
Selected AbstractsChemInform Abstract: A Short and Efficient Synthesis of 3-Spiro-,-methylene-,-butyrolactone Oxindolones from Isomerized Bromo Derivatives of Morita,Baylis,Hillman Adducts.CHEMINFORM, Issue 13 2009Ponnusamy Shanmugam Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] N - and C -acyclic thionuleoside analogues of 1,2,3-triazoleHETEROATOM CHEMISTRY, Issue 5 2004Najim A. Al-Masoudi Cycloaddition of the azide derivative 5 with 1,4-dihydroxybutyne afforded the N -thio-acyclic nucleoside 6, which prepared alternatively from coupling of the bromo derivative 8 with 2-acetoxy-ethylmercaptan. Deblocking of 6 gave the free nucleoside 7. Mesylation of 6 furnished the dimesylate 9, which gave three rearranged products 14,16 on treatment with chloride anion. These compounds might be obtained via the episulfonium ion 10, which is subjected to nucleophilic displacement and further sulfur participation. Deblocking of 14,16 afforded the free nucleoside analogues 17,19, and their structures were confirmed by COSY, ROESY, HMQC, and HMBC NMR techniques. Compound 16 was prepared alternatively from chlorination of alcohol 6 with Ph3P-CCl4. Carbomoylation of 6 led to the carbamate 20, which gave the free nucleoside analogue 21 on deblocking. © 2004 Wiley Periodicals, Inc. Heteroatom Chem 15:380,387, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20030 [source] Radiosynthesis of 2- exo -(2,-[18F]Fluoro-3,-(4-fluorophenyl)-pyridin-5,-yl)-7-azabicyclo[2.2.1]heptane ([18F]F2PhEP), a potent epibatidine-based radioligand for nicotinic acetylcholine receptor PET imagingJOURNAL OF LABELLED COMPOUNDS AND RADIOPHARMACEUTICALS, Issue 6 2006Gaėlle Roger Abstract 2- exo -(2,-Fluoro-3,-(4-fluorophenyl)-pyridin-5,-yl)-7-azabicyclo[2.2.1]heptane (F2PhEP), a novel, epibatidine-based, ,4,2-selective nicotinic acetylcholine receptor antagonist of low toxicity, as well as the corresponding N- Boc-protected chloro- and bromo derivatives as precursors for labelling with fluorine-18 were synthesized from 7- tert -butoxycarbonyl-7-azabicyclo[2.2.1]hept-2-ene in 13, 19 and 8% overall yield, respectively. [18F]F2PhEP was prepared in 8,9% overall yield (non-decay-corrected) using 1 mg of the bromo derivative in the following two-step radiochemical process: (1) no-carrier-added nucleophilic heteroaromatic ortho- radiofluorination with the activated K[18F]F-Kryptofix®222 complex in DMSO using microwave activation at 250 W for 90 s, followed by (2) quantitative TFA-induced removal of the N -Boc protective group. Radiochemically pure (>95%) [18F]F2PhEP (1.48,1.66 GBq, 74,148 GBq/µmol) was obtained after semi-preparative HPLC (Symmetry® C18, eluent aqueous 0.05 M NaH2PO4 CH3CN: 78/22 (v:v)) in 75,80 min starting from an 18.5 GBq aliquot of a cyclotron-produced [18F]fluoride production batch. Copyright © 2006 John Wiley & Sons, Ltd. [source] Straightforward Synthesis of (R)-(,)-KjellmanianoneCHEMISTRY - A EUROPEAN JOURNAL, Issue 4 2004Jens Christoffers Prof. Dr. Abstract A direct route to enantiomerically pure (,)-kjellmanianone is reported. The synthesis involves a cerium-catalyzed ,-hydroxylation and an enzyme-catalyzed procedure to resolve tertiary alcohols at key stages. The intermediate ,-oxo ester was ,-hydroxylated to give good yields of racemic kjellmanianone. The resolution of the racemic material was achieved by enzymatic saponification, followed by a chemical decarboxylation sequence to give enantiopure (,)-kjellmanianone with 99,% ee. Bromination then afforded the (,)-bromo derivative, whose X-ray structure provided evidence for the R configuration of (,)-kjellmanianone. [source] Radiosynthesis of 2- exo -(2,-[18F]Fluoro-3,-(4-fluorophenyl)-pyridin-5,-yl)-7-azabicyclo[2.2.1]heptane ([18F]F2PhEP), a potent epibatidine-based radioligand for nicotinic acetylcholine receptor PET imagingJOURNAL OF LABELLED COMPOUNDS AND RADIOPHARMACEUTICALS, Issue 6 2006Gaėlle Roger Abstract 2- exo -(2,-Fluoro-3,-(4-fluorophenyl)-pyridin-5,-yl)-7-azabicyclo[2.2.1]heptane (F2PhEP), a novel, epibatidine-based, ,4,2-selective nicotinic acetylcholine receptor antagonist of low toxicity, as well as the corresponding N- Boc-protected chloro- and bromo derivatives as precursors for labelling with fluorine-18 were synthesized from 7- tert -butoxycarbonyl-7-azabicyclo[2.2.1]hept-2-ene in 13, 19 and 8% overall yield, respectively. [18F]F2PhEP was prepared in 8,9% overall yield (non-decay-corrected) using 1 mg of the bromo derivative in the following two-step radiochemical process: (1) no-carrier-added nucleophilic heteroaromatic ortho- radiofluorination with the activated K[18F]F-Kryptofix®222 complex in DMSO using microwave activation at 250 W for 90 s, followed by (2) quantitative TFA-induced removal of the N -Boc protective group. Radiochemically pure (>95%) [18F]F2PhEP (1.48,1.66 GBq, 74,148 GBq/µmol) was obtained after semi-preparative HPLC (Symmetry® C18, eluent aqueous 0.05 M NaH2PO4 CH3CN: 78/22 (v:v)) in 75,80 min starting from an 18.5 GBq aliquot of a cyclotron-produced [18F]fluoride production batch. Copyright © 2006 John Wiley & Sons, Ltd. [source] | ||||||||||