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The Suzuki coupling Knoevenagel condensation one-pot synthesis of boronic acids/esters, (hetero)aromatic bromo aldehydes and methylene active compounds is a highly practical consecutive three-component process to provide substance libraries with 60 donor-π-bridge-acceptor molecules, i.e., merocyanines in a broader sense, in moderate to excellent yield. As already seen with the naked eye, a broad variation of the optical properties becomes accessible using this practical synthetic tool. More systematically, correlation analyses upon plotting the optical band gaps against the first oxidation potentials of redox active systems of consanguineous series furnishes linear correlations and, by extension, two parameter plots (oxidation potential and emission maximum) planar correlations with the optical band gaps. 相似文献
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Mitochondrial DNA sequence data are often utilized in disease studies, conservation genetics and forensic identification. The current approaches for sequencing the full mtGenome typically require several rounds of PCR enrichment during Sanger or MPS protocols followed by fairly tedious assembly and analysis. Here we describe an efficient approach to sequencing directly from genomic DNA samples without prior enrichment or extensive library preparation steps. A comparison is made between libraries sequenced directly from native DNA and the same samples sequenced from libraries generated with nine overlapping mtDNA amplicons on the Oxford Nanopore MinION? device. The native and amplicon library preparation methods and alternative base calling strategies were assessed to establish error rates and identify trends of discordance between the two library preparation approaches. For the complete mtGenome, 16 569 nucleotides, an overall error rate of approximately 1.00% was observed. As expected with mtDNA, the majority of error was detected in homopolymeric regions. The use of a modified basecaller that corrects for ambiguous signal in homopolymeric stretches reduced the error rate for both library preparation methods to approximately 0.30%. Our study indicates that direct mtDNA sequencing from native DNA on the MinION? device provides comparable results to those obtained from common mtDNA sequencing methods and is a reliable alternative to approaches using PCR‐enriched libraries. 相似文献
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Song Kedong Kong Qian Li Liying Wang Yiwei Parungao Roxanne Zheng Shuangshuang Nie Yi Jiao Zeren Wang Hongfei Liu Tianqing 《Applied biochemistry and biotechnology》2019,189(2):471-484
Applied Biochemistry and Biotechnology - A novel HAp-CS/Gel biomimetic osteoblastic niche was fabricated by freeze-drying, and its mechanical strength and biocompatibility were characterized.... 相似文献
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Dr. Lu Han Dr. Yijun Zheng Dr. Hao Luo Jun Feng Roxanne Engstler Lulu Xue Prof. Guangyin Jing Prof. Xu Deng Prof. Aránzazu del Campo Dr. Jiaxi Cui 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(14):5660-5664
A solid-to-hollow evolution in macroscopic structures is challenging in synthetic materials. A fundamentally new strategy is reported for guiding macroscopic, unidirectional shape evolution of materials without compromising the material's integrity. This strategy is based on the creation of a field with a “swelling pole” and a “shrinking pole” to drive polymers to disassemble, migrate, and resettle in the targeted region. This concept is demonstrated using dynamic hydrogels containing anchored acrylic ligands and hydrophobic long alkyl chains. Adding water molecules and ferric ions (Fe3+) to induce a swelling–shrinking field transforms the hydrogels from solid to hollow. The strategy is versatile in the generation of various closed hollow objects (for example, spheres, helix tubes, and cubes with different diameters) for different applications. 相似文献
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Kieltyka RE Bastings MM van Almen GC Besenius P Kemps EW Dankers PY 《Chemical communications (Cambridge, England)》2012,48(10):1452-1454
A convenient method to prepare supramolecular bioconjugates in a facile and scalable manner is by a modular approach, whereby self-assembling units and peptides are coupled using oxime chemistry. We here report syntheses of bioactive ureidopyrimidinone-based peptide conjugates, and their resultant self-assembly into fibrous structures. 相似文献
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Melanie Paul Melissa Teubner Dr. Benjamin Grimm-Lebsanft Christiane Golchert Yannick Meiners Laura Senft Kristina Keisers Dr. Patricia Liebhäuser Dr. Thomas Rösener Florian Biebl Sören Buchenau Dr. Maria Naumova Dr. Vadim Murzin Dr. Roxanne Krug Dr. Alexander Hoffmann Prof. Dr. Jörg Pietruszka Prof. Dr. Ivana Ivanović-Burmazović Prof. Dr. Michael Rübhausen Prof. Dr. Sonja Herres-Pawlis 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(34):7556-7562
The enzyme tyrosinase contains a reactive side-on peroxo dicopper(II) center as catalytically active species in C−H oxygenation reactions. The tyrosinase activity of the isomeric bis(μ-oxo) dicopper(III) form has been discussed controversially. The synthesis of bis(μ-oxo) dicopper(III) species [Cu2(μ-O)2( L1 )2](X)2 ([ O1 ](X)2, X=PF6−, BF4−, OTf−, ClO4−), stabilized by the new hybrid guanidine ligand 2-{2-((dimethylamino)methyl)phenyl}-1,1,3,3-tetramethylguanidine ( L1 ), and its characterization by UV/Vis, Raman, and XAS spectroscopy, as well as cryo-UHR-ESI mass spectrometry, is described. We highlight selective oxygenation of a plethora of phenolic substrates mediated by [ O1 ](PF6)2, which results in mono- and bicyclic quinones and provides an attractive strategy for designing new phenazines. The selectivity is predicted by using the Fukui function, which is hereby introduced into tyrosinase model chemistry. Our bioinspired catalysis harnesses molecular dioxygen for organic transformations and achieves a substrate diversity reaching far beyond the scope of the enzyme. 相似文献
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Fast,simple, and sensitive high‐performance liquid chromatography method for measuring vitamins A and E in human blood plasma
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Chao Yuan Maria Burgyan Dustin R. Bunch Edmunds Reineks Raymond Jackson Roxanne Steinle Sihe Wang 《Journal of separation science》2014,37(17):2293-2299
Vitamins A and E are fat‐soluble vitamins that play important roles in several physiological processes. Monitoring their concentrations is needed to detect deficiency and guide therapy. In this study, we developed a high‐performance liquid chromatography method to measure the major forms of vitamin A (retinol) and vitamin E (α‐tocopherol and γ‐tocopherol) in human blood plasma. Vitamins A and E were extracted with hexane and separated on a reversed‐phase column using methanol as the mobile phase. Retinol was detected by ultraviolet absorption, whereas tocopherols were detected by fluorescence emission. The chromatographic cycle time was 4.0 min per sample. The analytical measurement range was 0.03–5.14, 0.32–36.02, and 0.10–9.99 mg/L for retinol, α‐tocopherol, and γ‐tocopherol, respectively. Intr‐aassay and total coefficient of variation were <6.0% for all compounds. This method was traceable to standard reference materials offered by the National Institute of Standards and Technology. Reference intervals were established using plasma samples collected from 51 healthy adult donors and were found to be 0.30–1.20, 6.0–23.0, and 0.3–3.2 mg/L for retinol, α‐tocopherol, and γ‐tocopherol, respectively. In conclusion, we developed and validated a fast, simple, and sensitive high‐performance liquid chromatography method for measuring the major forms of vitamins A and E in human plasma. 相似文献
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A novel electron spin-reorientation transition is discovered by 13C NMR in the quasi-two-dimensional organic antiferromagnet kappa-(BEDT-TTF)(2)Cu[N(CN)(2)]Cl. The spin reorientation occurs as an external field is swept through the orientation of the characteristic vector of the Dzialoshinskii-Moriya (DM) interaction, thus providing a precise determination of the orientation of the DM vector. Such a spin reorientation could help to characterize the DM interaction in other antiferromagnetic systems. 相似文献