Search results for "Urea"
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Kontrola prasy oraz bibliotek przez urzędników Ministerstwa Informacji i Propagandy na przykładzie Powiatowego Urzędu Informacji i Propagandy w Opolu
2018
During the first phase of the communist rule in Poland, control over the press, publications and spectacles was distributed among various state institutions. Initially, the main unit responsible for this task was the Department of Information and Propaganda, transformed in late 1944 into the Ministry of Information and Propaganda. The field structures of the MolaP had two-level hierarchy, to which voivodeship bureaus and poviat bureaus of information and propaganda belonged. The present text aims at showing the competences of the officials of the aforementioned ministry, as well as the tasks connected therewith and performed by the employees of the Poviat Bureau of Information and Propagand…
Organocatalytic Enantioselective Functionalization of Hydroxyquinolines through an Aza-Friedel-Crafts Alkylation with Isatin-derived Ketimines
2018
[EN] A highly enantioselective addition of hydroxyquinolines to isatin-derived ketimines has been realized using a quinine-derived thiourea organocatalyst. The reaction affords chiral 3-amino-2-oxindoles bearing a quinoline moiety with a quaternary stereocenter in high yields (up to 98%) and excellent enantioselectivities (up to 99%). Moreover, we can extend this methodology for the enantioselective functionalization of 5-hydroxyisoquinoline. This methodology represents, to the best of our knowledge, the first enantioselective addition of hydroxyquinolines to imines.
Über die mikrobiologische Umwandlung N-haltiger Substrate. 4. Mitt.: Über die mikrobiologische Umwandlung von 5-Hydroxyindol durch Claviceps purpurea…
1968
Aus 5-Hydroxyindol wird durch den Claviceps purpurea-Stamm 47 A 5-Hydroxytryptophan und ω-N-Acetyl-5-hydroxy-tryptophan, durch Cordyceps militaris ω-N-Acetyl-5-hydroxytryptophan und ω-N-Acetyl-serotonin, durch Aspergillus oryzae nur ω-N-Acetyl-serotonin in der Schuttelkultur gebildet. 5-Hydroxyindole, added to submerged cultures, is converted into 5-hydroxytryptophan and ω-N-acetyl-5-hydroxytryptophan by Claviceps purpurea strain 47 A; into ω-N-acetyl-5-hydroxytryptophan and ω-N-acetyl-serotonin by Cordiceps militaris; and only into-ω-N-acetyl-serotonin by Aspergillus oryzae.
Typification of two Linnaean names: Centaurea aspera and Centaurea isnardii (Asteraceae)
2014
The typification of the names Centaurea aspera L. and C. isnardii L. (Asteraceae) is discussed. A lectotype for C. aspera is designated from original material conserved in UPS-BURSER (Joachim Burser Herbarium). Centaurea isnardii is typified by an illustration of Isnard (1719) confirming this name as a synonym of C. aspera subsp. aspera.
Volatile constituents of aerial parts of three endemicCentaureaspecies from Turkey:Centaurea amanicolaHub.-Mor.,CentaureaconsanguineaDC. andCentaurea…
2008
The volatile constituents of the aerial parts of Centaurea amanicola Hub.-Mor., Centaurea consanguinea DC. and Centaurea ptosimopappa Hayek were extracted by hydrodistillation and analysed by GC and GC–MS. Altogether 94 components were identified. Sesquiterpenoids, fatty acids and carbonylic compounds were the most abundant components in the oils. Hexadecanoic acid and (Z,Z )-9,12-octadecadienoic acid were the main fatty acids in all the examined samples, that showed different patterns of composition. The study on the biological activity of the oils showed an action mainly against the Gram-positive pathogens.
Norisoprenoids from Centaurea aspera and C. salmantica
1993
Abstract From aerial parts of Centaurea aspera var. subinermis a new homoderivative of the grasshopper ketone has been isolated. Its structure was deter
Volatile components ofCentaurea cineraria L. subsp.umbrosa (Lacaita) Pign. andCentaurea napifolia L. (Asteraceae), two species growing wild in Sicily
2003
The volatile components of the flowerheads of Centaurea cineraria L. subsp. umbrosa (Lacaita) Pign. and Centaurea napifolia L. were obtained by hydrodistillation and identified by GC and GC-MS. Altogether 55 components were identified, mostly sesquiterpenes and hydrocarbons. Copyright © 2003 John Wiley & Sons, Ltd.
Hydrogen-bonded dimers of tetra-urea calix[4]arenes stable in THF.
2007
[structure: see text]. Whereas tetra-urea derivatives of tetra-alkoxy calix[4]arenes 1 exist as single molecules in THF, dimeric hydrogen-bonded capsules are exclusively found for the corresponding calix[4]arene derivatives 3 and 2 with two or four free hydroxyl groups. Comparison with the rigidified tetra-urea 5 suggests that this increased stability of the dimers is due to the stabilization of their four-fold symmetry by intramolecular hydrogen bonds between the phenolic hydroxyl groups.
Tetra-urea calix[4]arenes 1,3-bridged at the narrow rim.
2009
The synthesis of special tetra-urea calix[4]arene derivatives is described. Two propyl ether groups in 1,3-position and a 5-iodo-isophthalamide bridge connecting two aminopropylether residues in 2,4-position at the narrow rim keep the molecule fixed in the cone conformation. The aryl urea residues are substituted by decyloxy groups in p-position to increase the solubility in apolar solvents, while the iodo substituent allows further functionalization. Two single crystal X-ray structures of 3 and 4 show a strongly pinched cone conformation in which the bridged phenol units are bent outwards, while the phenol units bearing the propyl ether groups are nearly parallel. The molecules are flexibl…
Incidence of heavy metals in the application of inorganic fertilizers to rice farming soils (Valencia, Spain)
1996
The presence of Cd, Co, Cu, Ni, Pb, Zn, Fe and Mn in different inorganic fertilizers (urea, calcium superphosphate, iron sulphate and copper sulphate) are evaluated and the contribution of these metals to the soils in this way is estimated. The studied zone corresponds to rice farming and is at the north of Albufera Natural Park (Valencia, Spain). The results obtained show that Superphosphate is the fertilizer that contains the highest levels of Cd, Co, Cu and Zn as impurities. Copper sulphate and iron sulphate have the most significant contents of Pb, and are the only fertilizers in which Ni is detected. The most significant additions of impurities that the soil received by agricultural pr…