Search results for "urea"
showing 10 items of 888 documents
CCDC 1478715: Experimental Crystal Structure Determination
2016
Related Article: Toni Mäkelä, Anniina Kiesilä, Elina Kalenius and Kari Rissanen|2016|Chem.-Eur.J.|22|14264|doi:10.1002/chem.201602362
CCDC 1469010: Experimental Crystal Structure Determination
2016
Related Article: Filip Topić and Kari Rissanen|2016|J.Am.Chem.Soc.|138|6610|doi:10.1021/jacs.6b02854
CCDC 1469011: Experimental Crystal Structure Determination
2016
Related Article: Filip Topić and Kari Rissanen|2016|J.Am.Chem.Soc.|138|6610|doi:10.1021/jacs.6b02854
CCDC 1469017: Experimental Crystal Structure Determination
2016
Related Article: Filip Topić and Kari Rissanen|2016|J.Am.Chem.Soc.|138|6610|doi:10.1021/jacs.6b02854
CCDC 880908: Experimental Crystal Structure Determination
2013
Related Article: N.Probst, A.Madarasz, A.Valkonen, I.Papai, K.Rissanen, A.Neuvonen, P.M.Pihko|2012|Angew.Chem.,Int.Ed.|51|8495|doi:10.1002/anie.201203852
The Greenland shark Somniosus microcephalus—Hemoglobins and ligand-binding properties
2017
A large amount of data is currently available on the adaptive mechanisms of polar bony fish hemoglobins, but structural information on those of cartilaginous species is scarce. This study presents the first characterisation of the hemoglobin system of one of the longest-living vertebrate species (392 +/- 120 years), the Arctic shark Somniosus microcephalus. Three major hemoglobins are found in its red blood cells and are made of two copies of the same a globin combined with two copies of three very similar beta subunits. The three hemoglobins show very similar oxygenation and carbonylation properties, which are unaffected by urea, a very important compound in marine elasmobranch physiology.…
Performance of PSI, CURB-65, and SCAP scores in predicting the outcome of patients with community-acquired and healthcare-associated pneumonia
2011
The objective was to compare three score systems, pneumonia severity index (PSI), the Confusion-Urea-Respiratory Rate-Blood pressure-65 (CURB-65), and severe community-acquired pneumonia (SCAP), for prediction of the outcomes in a cohort of patients with community-acquired (CAP) and healthcare-associated pneumonia (HCAP). Large multi-center, prospective, observational study was conducted in 55 hospitals. HCAP patients were included in the high classes of CURB-65, PSI and SCAP scores have a mortality rate higher than that of CAP patients. HCAP patients included in the low class of the three severity rules have a significantly higher incidence of adverse events, including development of septi…
Equipping metallo-supramolecular macrocycles with functional groups: Assemblies of pyridine-substituted urea ligands
2012
A series of di-(m-pyridyl)-urea ligands were prepared and characterized with respect to their conformations by NOESY experiments and crystallography. Methyl substitution in different positions of the pyridine rings provides control over the position of the pyridine N atoms relative to the urea carbonyl group. The ligands were used to self-assemble metallo-supramolecular M(2)L(2) and M(3)L(3) macrocycles which are generated in a finely balanced equilibrium in DMSO and DMF according to DOSY NMR experiments and ESI FTICR mass spectrometry. Again, crystallography was used to characterize the assemblies. Methyl substitution in positions next to the pyridine nitrogen prevents coordination, while …
Ion-Pair Complexation with Dibenzo[21]Crown-7 and Dibenzo[24]Crown-8 bis-Urea Receptors
2016
Synthesis and ion-pair complexation properties of novel ditopic bis-urea receptors based on dibenzo[21]crown-7 (R(1) ) and dibenzo[24]crown-8 (R(2) ) scaffolds have been studied in the solid state, solution, and gas phase. In a 4:1 CDCl3 /[D6 ]DMSO solution, both receptors clearly show positive heterotropic cooperativity toward halide anions when complexed with Rb(+) or Cs(+) , with the halide affinity increasing in order I(-) <Br(-) <Cl(-) . In solution, the rubidium complexes of both receptors have higher halide affinities compared to the caesium complexes. However, Rb(+) and Cs(+) complexes of R(2) show stronger affinities toward all the studied anions compared to the corresponding catio…
Thiourea-Catalyzed Domino Michael–Mannich [3+2] Cycloadditions: A Strategy for the Asymmetric Synthesis of 3,3′-Pyrrolidinyl-dispirooxindoles
2017
The asymmetric synthesis of trifluoromethylated 3,3′-pyrrolidinyl-dispirooxindole derivatives with four contiguous stereogenic centers, including two vicinal spiro-stereocenters, is described. Employing a bifunctional thiourea catalyst, a domino Michael–Mannich [3+2] cycloaddition occurs readily between isatin ketimines and isatin-derived enoates with good yields and very high stereoselectivities, providing a direct entry to the title compounds of potential medical value.