A simplified and improved synthesis of [11C] phosgene with iron and iron (III) oxide

K Nishijima, Y Kuge, K Seki, K Ohkura, N Motoki… - Nuclear medicine and …, 2002 - Elsevier
[ 11 C]Phosgene ([ 11 C]COCl 2 ), a useful precursor for labeling several radiopharmaceuticals,
is generally produced by catalytic oxidation of [ 11 C]carbon tetrachloride over Fe …

Synthesis and evaluation of radioiodinated cyclooxygenase-2 inhibitors as potential SPECT tracers for cyclooxygenase-2 expression

…, K Minematsu, K Seki, N Tamaki, K Ohkura… - Nuclear medicine and …, 2006 - Elsevier
Although several COX-2 inhibitors have recently been radiolabeled, their potential for
imaging COX-2 expression remains unclear. In particular, the sulfonamide moiety of COX-2 …

Separation and identification of taxifolin 3-O-glucoside isomers from Chamaecyparis obtusa (Cupressaceae)

…, K Ohno, M Coskun, K Seki, K Ohkura - Natural Product …, 2002 - Taylor & Francis
Taxifolin 3- O -glucoside isomers, [(2R, 3R)-, (2R, 3S)-, (2S, 3R)- and (2S, 3S)-] were isolated
from leaves of Chamaecyparis obtuse (Cupressaceae). Their structures were elucidated on …

Improvement of an efficient separation method for chemicals in diesel exhaust particles: analysis for nitrophenols

…, S Taneda, Y Mori, AK Suzuki, K Ohkura… - … Science and Pollution …, 2008 - Springer
Goal, scope, and background Diesel exhaust is believed to consist of thousands of organic
constituents and is a major cause of urban pollution. We recently reported that a systematic …

Guaiacylglycerol‐7′‐O‐methyl 8′‐vanillic acid ether and related compounds from Boreava orientalis

…, AM Ozkan, K Seki, K Ohkura - … Journal of Plant …, 2003 - Wiley Online Library
The threo and erythro forms of guaiacylglycerol‐7′‐O‐methyl 8′‐vanillic acid ethers,
threo and erythro guaiacylglycerol 8′‐vanillin ethers, and threo guaiacylglycerol 8′‐(4‐…

Increased [18F] 2-fluoro-2-deoxy-D-glucose ([18F] FDG) yield with recycled target [18O] water: factors affecting the [18F] FDG yield

…, Y Kuge, E Tsukamoto, K Seki, K Ohkura… - Applied radiation and …, 2002 - Elsevier
The reuse of [ 18 O] water after being purified by distillation has been reported to give lower
[ 18 F]2-fluoro-2-deoxy-d-glucose ([ 18 F]FDG) yields, probably due to the presence of …

Photo-arylation. IV. Synthesis of 2-arylpyridines by photo-reaction of 2-iodopyridine with substituted benzenes

…, K SEKI, C YOSHIDA, K OHKURA… - Chemical and …, 1985 - jstage.jst.go.jp
Photolysis of a mixture of 2—iodopyridi ‘ne and a variety of substituted benzenes in dichloro—methane
afforded the corresponding 2-ary1pyridines as isomeric mixtures. Based on the …

Synthesis of 1-β-D-(5-Deoxy-5-iodoarabinofuranosyl)-2-nitroimidazole (β-IAZA): A Novel Marker of Tissue Hypoxia

P Kumar, K Ohkura, D Beiki, LI Wiebe… - Chemical and …, 2003 - jstage.jst.go.jp
The present work describes the synthesis of the b-isomer of 1-aD-(5-deoxy-5-iodoarabinofuranosyl)-2-nitroimidazole
(IAZA). Radioiodinated IAZA (123I-IAZA) has been extensively …

The pyridyl cation as a reactive intermediate in the photoreaction of iodopyridines with benzenes

K Ohkura, K Seki, M Terashima, Y Kanaoka - Tetrahedron letters, 1989 - Elsevier
The electrophilic behavior of the reactive entity in the phtosubstitution of benzenes with 2-
iodopyridine was found to be ascribable to the intermediary 2-pyridyl cation, rather than to …

Synthesis of a radioiodinated thymidine phosphorylase inhibitor and its preliminary evaluation as a potential SPECT tracer for angiogenic enzyme expression

…, S Zhao, Y Kuge, N Tamaki, K Ohkura - Journal of Labelled …, 2008 - Wiley Online Library
The expression of thymidine phosphorylase (TP) is strongly associated with angiogenesis
in tumors and activation of antitumor agents. We designed a novel 5‐ 125 I‐labeled 6‐(2‐…