Results 171 to 180 of about 26,885 (224)

Localization of phosphoprotein C23 in nucleoli by immunological methods

Experimental Cell Research, 1981
Abstract Antiserum to a major phosphorylated nucleolar protein. C23 (MW 103000, pI 5.2) from Novikoff hepatoma was produced in rabbits. By immunodiffusion analysis, the antiserum produced precipitin bands and with various crude extracts of nucleoli, but not with extranucleolar or cytosol fractions.
M O, Olson, K, Guetzow, H, Busch
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Chemoenzymatic Synthesis of the C10−C23 Segment of Dictyostatin

Organic Letters, 2006
[reaction: see text] Employing enzymatic desymmetrization and resolution, respectively, the two aldehydes 8 and 20 were prepared. The precursor to aldehyde 8, meso-2,4-dimethylglutaric anhydride 3, could be obtained by base treatment of the diastereomeric mixture. Aldehyde 8 was extended to alkyne 10 by a Marshall reaction introducing four carbon atoms.
Evgeny, Prusov, Hartmut, Röhm, Martin E, Maier   +2 more
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Synthesis of the C23–C32 fragment of spirangien

Tetrahedron Letters, 2007
Abstract The synthesis of the C23–C32 fragment of spirangien A is reported using Evans’ alkylation, Evans–Metternich aldol reaction and a substrate controlled stereoselective reduction.
Michael Lorenz, Markus Kalesse
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A highly stereoselective synthesis of the C10–C23 fragment of (–)-dictyostatin

Chemical Communications, 2007
A highly stereoselective synthesis of the C10-C23 fragment of (-)-dictyostatin has been achieved using a Carreira alkynylation and a Marshall-Tamaru allenylzinc addition as key steps.
C. Monti, O. Sharon, C. Gennari
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Synthesis and Structural Revision of Symbiodinolide C23−C34 Fragment

The Journal of Organic Chemistry, 2009
Stereoselective synthesis of the C23-C34 fragment of symbiodinolide, which possesses the originally proposed stereochemistry, and its diastereomers was achieved in 19 steps from L-aspartic acid, respectively. Comparison of spectroscopic data of the synthetic products with those of the degraded product of symbiodinolide led to a structural revision of ...
Takeshi, Murata, Masayuki, Sano, Hiroyoshi, Takamura, Isao, Kadota, Daisuke, Uemura   +4 more
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A C23-type Modification of ThAs2

Nature, 1966
ThAs2 was reported to crystallize in the tetragonal Cu2Sb or C38 type of structure1. In an attempt to synthesize this phase by reacting arsenic with thorium powder at temperatures between 600° and 900° C, a new modification was obtained. This low-temperature form α-ThAs2 is orthorhombic and of the C23 type. Its lattice constants are:
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Nucleolin (C23), a physiological substrate for casein kinase II

Biochemical and Biophysical Research Communications, 1988
Nucleolin (C23), a 110 kDa phosphoprotein, which is mainly found in the nucleolus has been shown to be a physiological substrate for casein kinase II (CKII). Nucleolin was identified and characterized by immunodetection using an anti-nucleolin antibody.
H R, Schneider, O G, Issinger
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Association of protein C23 with rapidly labeled nucleolar RNA

Biochemistry, 1986
The association of nucleolar phosphoprotein C23 with preribosomal ribonucleoprotein (RNP) particles was examined in Novikoff hepatoma nucleoli. RNA was labeled with [3H]uridine for various times in cell suspensions, and RNP particles were extracted from isolated nucleoli and fractionated by sucrose gradient ultracentrifugation.
A H, Herrera, M O, Olson
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The determination of the absolute configuration at C23 in 23-hydroxylanosterol

Tetrahedron, 1969
The absolute configuration at C23 in the naturally occurring 23-hydroxylanosterol has been deduced to be S, and in its C23 epimer to be R, by correlation of their molecular rotations and that of lanosterol with those of R(−) and S(+) 4-methylpent-3-en-2-ol.
N. Entwistle, A.D. Pratt
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Studies on the C22-C23 Aldol Coupling of Spirangien

Synthesis, 2009
The aldol reaction is one of the most powerful and versatile methods in polyketide synthesis. Nevertheless, the subtle directing effects remain very often obscure and impede complex natural products syntheses. Here, we report studies on the pivotal aldol coupling employed in the spirangien synthesis.
Markus Kalesse, Michael Lorenz, Nadine Bluhm   +2 more
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