GLORIA — GEOMAR Library Ocean Research Information Access

Treffer pro Seite

Treffer 1 - 4 | 4 Treffer

Sortierung

Digitale Medien

Synthesis and Structure of Allenyl-Substituted η6-Benzene(tricarbonyl)-chromium Complexes (1997)

Müller, Thomas J. J. ; Ansorge, Markus

Weinheim : Wiley-Blackwell

Berichte der deutschen chemischen Gesellschaft 130 (1997), S. 1135-1139

zur Merkliste hinzufügen auf der Merkliste

Details

ISSN: 0009-2940

Schlagwort(e): Arene complexes ; Chromium ; Allenes ; Rearrangements ; Chemistry ; Inorganic Chemistry

Quelle: Wiley InterScience Backfile Collection 1832-2000

Thema: Chemie und Pharmazie

Notizen: The Cr(CO)3-complexed η6-phenylpropargylic alcohols 3 react in a displacement rearrangement with thionyl chloride or chlorodiphenylphosphane to give the chloro- or phosphoryl allenyl substituted η6-phenyl complexes 4 and 6, respectively. In the X-ray crystal structure of the novel organometallic allenic derivatives 4b and 6b the vicinal chloro or phosphoryl substituent and the benzene(tricarbonyl)chromium fragment are arranged coplanarily. Palladium/copper-catalyzed couplings of the chloroallene 4b with terminal alkynes disclose a facile access to ynallene derivatives 8, novel carbon-rich organometallic π-systems.

Zusätzliches Material: 1 Ill.

Materialart: Digitale Medien

URL: http://dx.doi.org/10.1002/cber.19971300816

Permalink

	Standort	Signatur	Einschränkungen	Verfügbarkeit

Andere fanden auch interessant ...

Artikel (Nationallizenzen)

Volltext

Digitale Medien

Sidechain Functionalizations by Cuprate Additions to Phosphorylallenyl-Substituted Arenetricarbonylchromium Complexes (1999)

Ansorge, Markus ; Polborn, Kurt ; Müller, Thomas J. J.

Weinheim : Wiley-Blackwell

Berichte der deutschen chemischen Gesellschaft 1999 (1999), S. 225-233

zur Merkliste hinzufügen auf der Merkliste

Details

ISSN: 1434-1948

Schlagwort(e): Arene complexes ; Chromium ; Sidechain functionalization ; Allenes ; Cuprates ; Chemistry ; General Chemistry

Quelle: Wiley InterScience Backfile Collection 1832-2000

Thema: Chemie und Pharmazie

Notizen: The cuprate addition to (arene)Cr(CO)3-substituted phosphorylallenes 1 gives rise to the regioselective formation of complexed allylphosphane oxide derivatives 3a-c and allylphosphonate derivatives 3d-j in good yields. In the case of racemic planar chiral ortho-substituted complexed (arylallenyl)phosphonates 1c, d the protonation of the intermediate allyl anion proceeds diastereoselectively due to the hindered rotation around the Cipso-Cα bond. This diastereoselective protonation is discussed on the basis of the conformational analysis as deduced from the X-ray structure analyses of the allenylphosphonate 1d and the allylphosphonates 3i, j.

Zusätzliches Material: 4 Ill.

Materialart: Digitale Medien

Permalink

	Standort	Signatur	Einschränkungen	Verfügbarkeit

Andere fanden auch interessant ...

Artikel (Nationallizenzen)

Digitale Medien

The role of erythropoietin in the production of principal erythrocyte proteins other than hemoglobin during terminal erythroid differentiation (1986)

Koury, Mark J. ; Bondurant, Maurice C. ; Mueller, Thomas J.

New York, NY [u.a.] : Wiley-Blackwell

Journal of Cellular Physiology 126 (1986), S. 259-265

zur Merkliste hinzufügen auf der Merkliste

Details

ISSN: 0021-9541

Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology

Quelle: Wiley InterScience Backfile Collection 1832-2000

Thema: Biologie , Medizin

Notizen: Erythropoietin (EP) controls the terminal phase of differentiation in which proerythroblasts and their precursors, the colony forming units-erythroid (CFU-e), develop into erythrocytes. Biochemical studies of this hormone-directed terminal differentiation have been hindered by the lack of a homogeneous population of erythroid cells at the developmental stages of CFU-e and proerythroblasts that will synchronously differentiate in response to EP. Such a population of cells can be prepared from the spleens of mice with the acute erythroblastosis resulting from infection with anemia-inducing Friend virus (FVA). Using these FVA-infected erythroid cells, which were induced to differentiate with EP, four proteins other than hemoglobin that have key functions in mature erythrocytes were monitored during the 48-hour period of terminal differentiation. Synthesis of spectrin and membrane band 3 proteins were determined by immunoprecipitation and SDS-polyacrylamide gel electrophoresis; accumulation of the cytoskeletal protein band 4.1 was monitored by immunoblotting; carbonic anhydrase activity was measured electro-metrically. Band 3 synthesis and band 4.1 accumulation could be detected only after exposure of the cells to EP. Spectrin synthesis was ongoing prior to culture with EP, but it did increase after exposure to the hormone. Carbonic anhydrase-specific activity changed very little throughout the terminal differentiation process. These results reveal at least three patterns of production of principal erythrocyte proteins during EP-mediated terminal differentiation of FVA-infected erythroid cells. Depending on the specific protein examined, de novo synthesis can be induced by EP, an ongoing production can be enhanced by EP, or the production of a protein can be completed at a developmental stage prior to EP-mediated differentiation in these cells.

Zusätzliches Material: 5 Ill.

Materialart: Digitale Medien

URL: http://dx.doi.org/10.1002/jcp.1041260216

Permalink

	Standort	Signatur	Einschränkungen	Verfügbarkeit

Andere fanden auch interessant ...

Artikel (Nationallizenzen)

Volltext

Digitale Medien

Monolayer freeze-fracture - a modified procedure (1986)

Edwards, Harold H. ; Mueller, Thomas J. ; Morrison, Martin

New York, NY : Wiley-Blackwell

Journal of Electron Microscopy Technique 3 (1986), S. 439-451

zur Merkliste hinzufügen auf der Merkliste

Details

ISSN: 0741-0581

Schlagwort(e): Monolayer freeze-fracture ; Trans-membrane proteins ; Erythrocyte membrane proteins ; Life and Medical Sciences ; Cell & Developmental Biology

Quelle: Wiley InterScience Backfile Collection 1832-2000

Thema: Allgemeine Naturwissenschaft

Notizen: Monolayer freeze-fracture of biological membranes is a valuable tool for integrating membrane morphology with biochemical analysis of membrane components. This correlation has been restricted by the purity of the biochemical sample. In this article, the method is reviewed, and an improved method is described. The essential modification was the use of a polysaccharide-coated microscope slide, instead of a copper plate, to cover cells attached to a polylysine-coated coverslip. It was found that proper freeze-fracture will not occur unless there is a distinct temperature gradient, with its accompanying stresses, across the cell monolayer during the freezing process. This gradient is achieved by using glass slides of different thickness to cover each side of the monolayer. Comparison of the results with those obtained when using a copper-glass system demonstrated a consistently purer sample for the glass-glass system, with whole-cell contamination of the external membrane leaflet being reduced to 0.4%. Problems associated with obtaining pure samples for biochemical analysis are discussed, and the results of freeze-fracture with the glass-glass and glass-copper systems are compared. Sodium dodecyl sulfate polyacrylamide gel electrophoresis of polypeptides associated with the separate halves of the erythrocyte membrane demonstrated that band 3, the anion transport protein, separates with the cytoplasmic face, whereas only sialoglycoproteins and their fragments are retained in the external face. This finding, obtained with the glass-glass system, is consistent with results of our earlier freeze-fracture study that used a copper-glass system which showed that covalent bonds may be broken during this procedure.

Zusätzliches Material: 10 Ill.

Materialart: Digitale Medien

URL: http://dx.doi.org/10.1002/jemt.1060030407

Permalink

	Standort	Signatur	Einschränkungen	Verfügbarkeit

Andere fanden auch interessant ...

Artikel (Nationallizenzen)

Volltext

Treffer 1 - 4 | 4 Treffer