Florbetapir F-18 is a molecular imaging agent combining high affinity for β-amyloid, pharmacokinetic properties that allow positron emission tomography (PET) imaging within a convenient time after dose administration, and the wide availability of the radionuclide fluorine-18. Florbetapir F-18 is prepared by nucleophilic radiofluorination in approximately 60 minutes with a decay-corrected yield of 20%-40% and with a specific activity typically exceeding 100 Ci/mmol. The florbetapir F-18 dissociation constant (K(d)) for binding to β-amyloid in brain tissue from Alzheimer's disease (AD) patients was 3.
View Article and Find Full Text PDFUnlabelled: beta-amyloid plaques (Abeta plaques) in the brain, containing predominantly fibrillary Abeta peptide aggregates, represent a defining pathologic feature of Alzheimer disease (AD). Imaging agents targeting the Abeta plaques in the living human brain are potentially valuable as biomarkers of pathogenesis processes in AD. (E)-4-(2-(6-(2-(2-(2-(18)F-fluoroethoxy)ethoxy)ethoxy)pyridin-3-yl)vinyl)-N-methyl benzenamine ((18)F-AV-45) is such as an agent currently in phase III clinical studies for PET of Abeta plaques in the brain.
View Article and Find Full Text PDFWe report a series of radioiodinated styrylpyridines as single photon emission computed tomography probes for imaging Abeta plaques in the brain of patients with Alzheimer's disease (AD). In vitro binding showed that all of the styrylpyridines displayed very good binding affinities in postmortem AD brain homogenates (Ki = 3.6 to 15.
View Article and Find Full Text PDF[reaction: see text] 2,5-disubstituted and 2,4,5-trisubstituted oxazol-5-yl carbonyl compounds were prepared in good yields by a mild SiO2-mediated cycloisomerization of propargyl amides.
View Article and Find Full Text PDF[reaction: see text] The synthesis of stable, C-linked analogues of glycopeptides is being investigated with two complementary synthetic strategies, co-translational and post-translational glycopeptide synthesis. The key feature of the present approach lies in an effective olefin cross-metathesis reaction that allows formation of both glycoamino acids and glycopeptides.
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