Search results for "synthesis"
showing 10 items of 2844 documents
COX-1/COX-2 inhibitors based on the methanone moiety
2002
This paper focuses on the synthesis and the in vitro testing of dual COX-1/COX-2 inhibitors. Starting from structures of non-steroidal anti-inflammatory drugs (NSAIDs) the diaryl methanone element was chosen as a lead. Modifications were carried out on this scaffold to obtain potent inhibitors of the COX enzymes. The N-(2-aroylphenyl)sulphonamides and -amides were studied in detail, and to consolidate the data evaluated the corresponding 3- and 4-regioisomers were also investigated. The potency and the enzyme selectivity were varied by structural modifications of the lead.
Enhanced platelet thromboxane synthesis and reduced macrophage-dependent fibrinolytic activity related to oxidative stress in oral contraceptive-trea…
1996
Abstract In previous studies conducted in rats and in women, we have shown that oral contraceptive (OC) administration induced a platelet hyperaggregation simultaneously with an increased platelet lipid biosynthesis which might be related to lipid peroxidation. In the present study, we specifically studied the arachidonic acid and the fibrinolytic pathways in relation to the fatty acid composition in female rats treated for 6 weeks with OC (ethinyl estradiol plus lynestrenol). We found that platelets of treated animals were not only hyper-responsive to thrombin and ADP, but also to sodium arachidonate. In addition, the results of the thrombin-induced release of labeled arachidonic acid pre-…
Influence of metal ions on the structures of Keggin polyoxometalate-based solids: Hydrothermal syntheses, crystal structures and magnetic properties
2006
Abstract Three new Keggin polyoxometalate (POM)-based compounds linked to 3d metal complexes have been synthesized under hydrothermal conditions: [Cu(phen)2]2{[Cu(phen)]2 [SiMo12O40(VO)2]} (1), {[Zn(phen)2]2[GeMo12O40(VO)2]}{[Zn(phen)2(H2O)]2 [GeMo12O40(VO)2]}·3H2O (2) and {[Co(phen)2]2[PMo12O40(VO)2]}{[Co(phen)2(OH)]2 [PMo12O40(VO)2]}·2.5H2O (3) (phen=1,10-phenanthroline). These three compounds present, as building blocks, the bicapped Keggin anions [XMo12O40(VO)2] (X=Si, Ge and P). Compound 1 consists of a bicapped Keggin anion [SiMo12O40(VO)2]2− linked to two [Cu(phen)]+ complexes with two [Cu(phen)2]+ countercations. Compound 2 contains two bicapped Keggin anions [GeMo12O40(VO)2]4−, one…
Distribution of Cartilage Proteoglycan (Aggrecan) Core Protein and Link Protein Gene Expression during Human Skeletal Development
1991
The distribution of cartilage proteoglycan core protein (aggrecan) and cartilage proteoglycan link protein was investigated by in situ hybridization during different stages of human skeletal development. Aggrecan and link protein expression were confined to chondrocytes of the developing skeleton and other cartilaginous structures. Distribution and intensity of the signal was identical with aggrecan as compared to link protein probes. Parallel to the calcification of cartilaginous matrix, chondrocytes of this area lost the expression of aggrecan and link protein specific mRNA and stayed negative throughout the following stages of skeletal development. Highest expression was found in the low…
Osteosynthesetechniken bei proximalen Humerusfrakturen
2001
Proximale Humerusfrakturen sind haufige Verletzungen. Die Frage der optimalen osteosynthetischen Behandlung instabiler und dislozierter 2- bis 4-Segmentfrakturen ist nach wie vor nicht einhellig geklart. Die operative Therapie befindet sich in der Konfliktsituation zwischen der Forderung einer anatomischen Reposition und stabilen Frakturretention auf der einen Seite und der Notwendigkeit einer maximalen intraoperativen Schonung der periglenohumeralen Weichteilstrukturen und Blutversorgung des Oberarmkopfs, mit dem Ziel das iatrogene Risiko der avascularen Kopfnekrose zu minimieren, andererseits. Wahrend Minimalosteosynthesen, bei denen die Reposition indirekt oder percutan erfolgt, Vorteile…
Zur erweitrten Indikationsstellung der Herbert-Schrauben-Osteosynthese
1995
Since 1984 the typical headless double threaded Herbert/Whipple screw is known in managing scaphoid fractures and scaphoid non-unions. We resume technical, biomechanical and histological aspects to point out advantages and disadvantages of this osteosynthesis. Our case review of 39 patients illustrate the same good results as achieved in treating scaphoid injuries, when using the Herbert/Whipple screw of a larger diameter for expanded indications other than scaphoid fractures, such as humeral- or radial-head fractures, Jones fractures and others.
Use of Boron‐Doped Diamond Electrodes in Electro‐Organic Synthesis
2019
Anodic coupling of guaiacol derivatives on boron-doped diamond electrodes.
2011
The anodic treatment of guaiacol derivatives on boron-doped diamond electrodes (BDD) provides a direct access to nonsymmetrical biphenols, which would require a multistep sequence by conventional methods. Despite the destructive nature of BDD anodes they can be exploited for chemical synthesis.
The Catalytic Mechanism of Steroidogenic Cytochromes P450 from All-Atom Simulations: Entwinement with Membrane Environment, Redox Partners, and Post-…
2019
Cytochromes P450 (CYP450s) promote the biosynthesis of steroid hormones with major impact on the onset of diseases such as breast and prostate cancers. By merging distinct functions into the same catalytic scaffold, steroidogenic CYP450s enhance complex chemical transformations with extreme efficiency and selectivity. Mammalian CYP450s and their redox partners are membrane-anchored proteins, dynamically associating to form functional machineries. Mounting evidence signifies that environmental factors are strictly intertwined with CYP450s catalysis. Atomic-level simulations have the potential to provide insights into the catalytic mechanism of steroidogenic CYP450s and on its regulation by e…
One-Pot Synthesis and AFM Imaging of a Triangular Aramide Macrocycle
2014
Macrocyclizations in exceptionally good yields were observed during the self-condensation of N-benzylated phenyl p-aminobenzoates in the presence of LiHMDS to yield three-membered cyclic aramides that adopt a triangular shape. An ortho-alkyloxy side chain on the N-benzyl protecting group is necessary for the macrocyclization to occur. Linear polymers are formed exclusively in the absence of this Li-chelating group. A model that explains the lack of formation of other cyclic congeners and the demand for an N-(o-alkoxybenzyl) protecting group is providedon the basis of DFT calculations.High-resolution AFM imaging of the prepared molecular triangles on a calcite(10.4) surface shows individual …