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161.
Different Complexation Behavior of P‐Functionalized Ferrocene Derivatives Towards SnCl2, SnCl4 and SnPh2Cl2: Auto‐ionization and Redox‐Type Reactions 下载免费PDF全文
Dipl.‐Chem. Matthias Gawron Dr. Christina Dietz Michael Lutter Dr. Andrew Duthie Prof. Dr. Viatcheslav Jouikov Prof. Dr. Klaus Jurkschat 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(46):16609-16622
The novel phosphonyl‐substituted ferrocene derivatives [Fe(η5‐Cp)(η5‐C5H3{P(O)(O‐iPr)2}2‐1,2)] ( Fc1,2 ) and [Fe{η5‐C5H4P(O)(O‐iPr)2}2] ( Fc1,1′ ) react with SnCl2, SnCl4, and SnPh2Cl2, giving the corresponding complexes [(Fc1,2)2SnCl][SnCl3] ( 1 ), [{(Fc1,1′)SnCl2}n] ( 2 ), [(Fc1,1′)SnCl4] ( 3 ), [{(Fc1,1′)SnPh2Cl2}n] ( 4 ), and [(Fc1,2)SnCl4] ( 5 ), respectively. The compounds are characterized by elemental analyses, 1H, 13C, 31P, 119Sn NMR and IR spectroscopy, 31P and 119Sn CP‐MAS NMR spectroscopy, cyclovoltammetry, electrospray ionization mass spectrometry, and single‐crystal as well as powder X‐ray diffraction analyses. The experimental work is accompanied by DFT calculations, which help to shed light on the origin for the different reaction behavior of Fc1,1′ and Fc1,2 towards tin(II) chloride. 相似文献
162.
163.
Targeting the Two Oncogenic Functional Sites of the HPV E6 Oncoprotein with a High‐Affinity Bivalent Ligand 下载免费PDF全文
164.
Structure Elucidation and Activity of Kolossin A,the D‐/L‐Pentadecapeptide Product of a Giant Nonribosomal Peptide Synthetase 下载免费PDF全文
Prof. Dr. Helge B. Bode Dr. Alexander O. Brachmann Dr. Kirtikumar B. Jadhav Dr. Lydia Seyfarth Dipl.‐Chem. Christina Dauth Dr. Sebastian W. Fuchs Dr. Marcel Kaiser Dr. Nick R. Waterfield Dipl.‐Phys. Holger Sack Prof. Dr. Stefan H. Heinemann Prof. Dr. Hans‐Dieter Arndt 《Angewandte Chemie (International ed. in English)》2015,54(35):10352-10355
The largest continuous bacterial nonribosomal peptide synthetase discovered so far is described. It consists of 15 consecutive modules arising from an uninterrupted, fully functional gene in the entomopathogenic bacterium Photorhabdus luminescens. The identification of its cryptic biosynthesis product was achieved by using a combination of genome analysis, promoter exchange, isotopic labeling experiments, and total synthesis of a focused collection of peptide candidates. Although it belongs to the growing class of D ‐/ L ‐peptide natural products, the encoded metabolite kolossin A was found to be largely devoid of antibiotic activity and is likely involved in interspecies communication. A stereoisomer of this peculiar natural product displayed high activity against Trypanosoma brucei rhodesiense, a recalcitrant parasite that causes the deadly disease African sleeping sickness. 相似文献
165.
166.
Christian G. Schfer Christina Lederle Kristina Zentel Bernd Stühn Markus Gallei 《Macromolecular rapid communications》2014,35(21):1852-1860
In this work, the preparation of highly thermoresponsive and fully reversible stretch‐tunable elastomeric opal films featuring switchable structural colors is reported. Novel particle architectures based on poly(diethylene glycol methylether methacrylate‐co‐ethyl acrylate) (PDEGMEMA‐co‐PEA) as shell polymer are synthesized via seeded and stepwise emulsion polymerization protocols. The use of DEGMEMA as comonomer and herein established synthetic strategies leads to monodisperse soft shell particles, which can be directly processed to opal films by using the feasible melt‐shear organization technique. Subsequent UV crosslinking strategies open access to mechanically stable and homogeneous elastomeric opal films. The structural colors of the opal films feature mechano‐ and thermoresponsiveness, which is found to be fully reversible. Optical characterization shows that the combination of both stimuli provokes a photonic bandgap shift of more than 50 nm from 560 nm in the stretched state to 611 nm in the fully swollen state. In addition, versatile colorful patterns onto the colloidal crystal structure are produced by spatial UV‐induced crosslinking by using a photomask. This facile approach enables the generation of spatially cross‐linked switchable opal films with fascinating optical properties. Herein described strategies for the preparation of PDEGMEMA‐containing colloidal architectures, application of the melt‐shear ordering technique, and patterned crosslinking of the final opal films open access to novel stimuli‐responsive colloidal crystal films, which are expected to be promising materials in the field of security and sensing applications.
167.
Sinner FM Gatschelhofer C Mautner A Magnes C Buchmeiser MR Pieber TR 《Journal of chromatography. A》2008,1191(1-2):274-281
Monolithic capillary columns were prepared via ring-opening metathesis polymerization (ROMP) using norborn-2-ene (NBE) and 1, 4, 4a, 5, 8, 8a-hexahydro-1, 4, 5, 8-exo,endo-dimethanonaphthalene (DMN-H6) as monomers. The monolithic polymer was copolymerized with Grubbs-type initiator RuCl(2)(PCy(3))(2)(CHPh) and a suitable porogenic system within the confines of fused silica capillaries of different inner diameter (I.D.). The first part of the study focused on batch-to-batch reproducibility of ROMP-derived capillary monoliths. Capillary monoliths of 200 microm I.D. showed good reproducibility in terms of retention times, with relative standard deviations (RSD) of 1.9% for proteins and 2.2% for peptides. However, the separately synthesized capillary monoliths revealed pronounced variation in back pressure with RSD values of up to 31%. These variations were considerably reduced by cooling of the capillaries during polymerization. Using this optimized preparation procedure capillary monoliths of 100 and 50 microm I.D. were synthesized and the effects of scaling down the column I.D. on the morphology and on the reproducibility of the polymerization process were investigated. In the second part, the applicability of ROMP-derived capillary monoliths to a separation problem common in medical research was assessed. A 200 microm I.D. monolithic column demonstrated excellent separation behavior for insulin and various insulin analogs, showing equivalent separation performance to Vydac C4 and Zorbax C3-based stationary phases. Moreover, the high permeability of monoliths enabled chromatographic separations at higher flow rates, which shortened analysis time to about one third. For the analysis of insulin in human biofluid samples, enhanced sensitivity was achieved by using a 50 microm I.D. ROMP-derived monolith. 相似文献
168.
Buse C Altmann F Amann B Hauck SM Poulsen Nautrup C Ueffing M Stangassinger M Deeg CA 《Electrophoresis》2008,29(6):1325-1332
There is increasing evidence that a large proportion of dilated cardiomyopathy (DCM) cases are mediated by autoimmune processes. Since DCM is a fatal disorder with rapid aggravation and is the leading cause of heart transplantation, further insights into disease pathogenesis are needed. Recent studies have separated the pathogenic capacity of autoantibodies and initial clinical trials removing such autoantibodies via immunoadsorption have been promising. In order to elucidate the full autoantibody repertoire involved in DCM, we applied an autoantibody screening test using ventricular and atrial proteomes as autoantigenic sources and subsequently tested the autoantibody-binding patterns of sera from dogs with spontaneous DCM. With this method, we detected five potentially DCM-related autoantigens which were identified by MS as being: myosin heavy chain cardiac muscle alpha isoform, alpha cardiac actin, mitochondrial aconitate hydratase, glyceraldehyde-3-phosphate dehydrogenase (GAPDH), and brain glycogen phosphorylase (GPBB). The recovery of two known DCM autoantigens (myosin heavy chain and alpha cardiac actin) and the discovery of three novel autoantigens (mitochondrial aconitate hydratase, GADPH, and GPBB) underscore the efficacy of this experimental method and the significance of the spontaneous canine DCM model. 相似文献
169.
Kontoyianni C Sideratou Z Theodossiou T Tziveleka LA Tsiourvas D Paleos CM 《Macromolecular bioscience》2008,8(9):871-881
A hyperbranched aliphatic polyester has been functionalized with PEG chains to afford a novel water-soluble BH40-PEG polymer which exhibits unimolecular micellar properties, and is therefore appropriate for application as a drug-delivery system. The solubility of the anticancer drug paclitaxel was enhanced by a factor of 35, 110, 230, and 355 in aqueous solutions of BH40-PEG of 10, 30, 60, and 90 mg x mL(-1), respectively. More than 50% of the drug is released at a steady rate and release is almost complete within 10 h. The toxicity of BH40-PEG was assessed in vitro with A549 human lung carcinoma cells and found to be nontoxic for 3 h incubation up to a 1.75 mg x mL(-1) concentration while LD50 was 3.5 mg x mL(-1). Finally, it was efficiently internalized in cells, primarily in the absence of foetal bovine serum, while confocal microscopy revealed the preferential localization of the compound in cell nuclei. [Figure: see text]. 相似文献
170.