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1.
Markus Leutzsch Alexander Roth Katrin Steinke Dieter Sicker Hans‐Ullrich Siehl Maximilian Schmid Klaus‐Peter Zeller Stefan Berger 《Chemie in Unserer Zeit》2013,47(6):344-354
3‐O‐Acetyl‐11‐keto‐β‐boswelliasäure was extracted from pulverized frankincense and purified by HPLC. All analytical spectra were recorded and are reproduced either in the main part or in the supporting information. The NMR‐ and mass‐spectra have been interpreted and compared with theoretical calculations of the 13C chemical shifts. The project is a follow up of the recent book “Classics in Spectroscopy” by S. Berger und D. Sicker (Wiley‐VCH 2009). 相似文献
2.
Katrin Steinke Elena Jose Hans‐Ullrich Siehl Klaus‐Peter Zeller Stefan Berger 《Chemie in Unserer Zeit》2013,47(1):56-60
Cocaine was isolated from dried tea leaves and chromatographically purified by HPLC. The UV‐, CD‐, IR‐ NMR‐ und MS‐spectra are reproduced in the supplementary material. The NMR‐ and mass‐spectra have been interpreted and compared with theoretical calculations of the 13C chemical shifts. The project is a follow up of the recent book “Classics in Spectroscopy” by S. Berger und D. Sicker (Wiley‐VCH 2009). 相似文献
3.
Anna Rudo Hans‐Ullrich Siehl Klaus‐Peter Zeller Stefan Berger Dieter Sicker 《Chemie in Unserer Zeit》2013,47(5):310-316
Cantharidin was extracted from dried Spanish Flys (Lytta vesicatoria) and purified by sublimation. All analytical spectra were recorded and are reproduced either in the main part or in the supporting information. The NMR‐ and mass‐spectra have been interpreted and compared with theoretical calculations of the 13C chemical shifts. The project is a follow up of the recent book “Classics in Spectroscopy” by S. Berger and D. Sicker (Wiley‐VCH 2009). 相似文献
4.
Johannes Appun Hans‐Ullrich Siehl Klaus‐Peter Zeller Katrin Steinke Stefan Berger Dieter Sicker 《Chemie in Unserer Zeit》2014,48(1):36-44
Colchicin was extracted from grinded seeds of meadow saffron and purified by flash chromatography and preparative HPLC. All analytical spectra were recorded and are reproduced either in the main part or in the supporting information. The NMR‐ and mass‐spectra have been interpreted and compared with theoretical calculations of the 13C chemical shifts. The project is a follow up of the recent book “Classics in Spectroscopy” by S. Berger und D. Sicker (Wiley‐VCH 2009). 相似文献
5.
Markus Winkler Katrin Steinke Ramona Oehme Stefan Berger Dieter Sicker Hans‐Ullrich Siehl Klaus‐Peter Zeller 《Chemie in Unserer Zeit》2014,48(3):190-199
Raffinose has been obtained by extraction with 50% ethanol from the seeds of the Sweet Blue Lupine and purified first via a Cation exchange column and finally by analytical HPLC using a RI‐detector. All analytical spectra were recorded and are reproduced either in the main part or in the supporting information. The NMR‐ and mass‐spectra have been interpreted and compared with theoretical calculations of the 13C chemical shifts. The project is a follow up of the recent book “Classics in Spectroscopy” by S. Berger und D. Sicker (Wiley‐VCH 2009). 相似文献
6.
Agneta Prasse Hans‐Ullrich Siehl Klaus‐Peter Zeller Stefan Berger Dieter Sicker 《Chemie in Unserer Zeit》2014,48(5):342-353
Both enantiomeric forms of Linalool have been obtained by vacuum distillation from the oils of Rosewood or Coriander. Subsequently they have been purified by column chromatography. All analytical spectra were recorded and are reproduced either in the main part or in the supporting information. The NMR‐ and mass‐spectra have been interpreted and compared with theoretical calculations of the 13C chemical shifts. The project is a follow up of the recent book “Classics in Spectroscopy” by S. Berger und D. Sicker (Wiley‐VCH 2009). 相似文献
7.
Facile prepolymerization and postpolymerization functionalization approaches to prepare well‐defined fluorescent conjugated glycopolymers through Cu(I)‐catalyzed azide/alkyne “Click” ligation were explored. Two well‐defined carbazole‐based fluorescent conjugated glycopolymers were readily synthesized based on these strategies and characterized by 1H NMR, 13C NMR, IR spectra, and UV‐vis spectra. The “Click” ligation offers a very effective conjugation method to covalently attach carbohydrate residues to fluorescent conjugated polymers. In addition, the studies of carbohydrate–lectin interactions were performed by titration of concanavalin A (Con A) to D ‐glucose‐bearing poly(anthracene‐alt‐carbazole) copolymer P‐2 resulting in significant fluorescence quenching of the polymer due to carbohydrate–lectin interactions. When peanut agglutinin (PNA) was added, no distinct change in the fluorescent properties of P‐2 was observed. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 2948–2957, 2009 相似文献
8.
Franziska Schulze Juliane Titus Peter Mettke Stefan Berger Hans‐Ullrich Siehl Klaus‐Peter Zeller Dieter Sicker 《Chemie in Unserer Zeit》2013,47(4):222-228
Carminic acid was isolated from dried Dactylopius coccus Costa (Dactylopiidae) and chromatographically purified. All analytical spectra were recorded and are reproduced either in the main part or in the supplementary material. The NMR‐ and mass‐spectra have been interpreted and compared with theoretical calculations of the 13C chemical shifts. The project is a follow up of the recent book “Classics in Spectroscopy” by S. Berger und D. Sicker (Wiley‐VCH 2009). 相似文献
9.
Katrin Steinke Elena Jose Dieter Sicker Hans‐Ullrich Siehl Klaus‐Peter Zeller Stefan Berger 《Chemie in Unserer Zeit》2013,47(3):158-163
Sinensetin was isolated from cold pressed orange peel oil and recrystallized from ethanol. All analytical spectra were recorded and are reproduced either in the main part or in the supporting information (www.chiuz.de). The NMR‐ and mass‐spectra have been interpreted and compared with theoretical calculations of the 13C chemical shifts. The project is a follow up of the book “Classics in Spectroscopy” by S. Berger und D. Sicker (Wiley‐VCH 2009). 相似文献
10.
Sandro Spiller Peter Mettke Hans‐Ullrich Siehl Klaus‐Peter Zeller Dieter Sicker Stefan Berger 《Chemie in Unserer Zeit》2014,48(2):114-122
Thymoquinone has been obtained by steam distillation from the yellow cold pressed oil of the seeds of Nigella sativa L. and purified by column chromatography. All analytical spectra were recorded and are reproduced either in the main part or in the supporting information. The NMR‐ and mass‐spectra have been interpreted and compared with theoretical calculations of the 13C chemical shifts. The project is a follow up of the recent book “Classics in Spectroscopy” by S. Berger und D. Sicker (Wiley‐VCH 2009). 相似文献
11.
Thermochromism of CuI Tetrakisguanidine Complexes: Reversible Activation of Metal‐to‐Ligand Charge‐Transfer Bands 下载免费PDF全文
Sven Wiesner Arne Wagner Dr. Olaf Hübner Dr. Elisabeth Kaifer Prof. Hans‐Jörg Himmel 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(46):16494-16503
Tetranuclear, intensely blue‐coloured CuI complexes were synthesised in which two Cu2X3? units (X=Br or I) are bridged by a dicationic GFA (guanidino‐functionalised aromatic) ligand. The UV/Vis spectra show a large metal‐to‐ligand charge‐transfer (MLCT) band around 638 nm. The tetranuclear “low‐temperature” complexes are in a temperature‐dependent equilibrium with dinuclear CuI “high‐temperature” complexes, which result from the reversible elimination of two CuX groups. A massive thermochromism effect results from the extinction of the strong MLCT band upon CuX elimination with increasing temperature. For all complexes, quantum chemical calculations predict a small and method‐dependent energy difference between the possible electronic structures, namely CuI and dicationic GFA ligand (closed‐shell singlet) versus CuII and neutral GFA ligand (triplet or broken‐symmetry state). The closed‐shell singlet state is disfavoured by hybrid‐DFT functionals, which mix in exact Hartree–Fock exchange, and is favoured by larger basis sets and consideration of a polar medium. 相似文献
12.
Subhankar Sardar Amit Kumar Paul Rahul Sharma Satrajit Adhikari 《International journal of quantum chemistry》2011,111(12):2741-2759
We explore the workability of a parallelized algorithm of time‐dependent discrete variable representation (TDDVR) methodology formulated by involving “classical” trajectories on each DOF of a multi‐mode multi‐state Hamiltonian to reproduce the population dynamics, photoabsorption spectra and nuclear dynamics of the benzene radical cation. To perform such dynamics, we have used a realistic model Hamiltonian consists of five lowest electronic states (X2E1g, B2E2g, C2A2u, D2E1u, and E2B2u) which are interconnected through several conical intersections with nine vibrational modes. The calculated nuclear dynamics and photoabsorption spectra with the advent of our parallelized TDDVR approach show excellent agreement with the results obtained by multiconfiguration time‐dependent Hartree method and experimental findings, respectively. The major focus of this article is to demonstrate how the “classical” trajectories for the different modes and the “classical” energy functional for those modes on each surface can enlight the time‐dependent feature of nuclear density and its' nodal structure. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem, 2011 相似文献
13.
《Journal of separation science》2017,40(16):3311-3317
1‐Hexadecyl‐3‐methylimidazolium bis(trifluoromethylsulfonyl)imide is a solid‐phase ionic organic material under ambient temperature and is considered as a kind of “frozen” ionic liquid. Because of their solid‐state and ultra‐hydrophobicity, “frozen” ionic liquids are able to be confined in the pores of hollow fiber, based on which a simple method was developed for the hollow‐fiber solid‐phase microextraction of dichlorodiphenyltrichloroethane and its main metabolites. Under optimized conditions, the proposed method results in good linearity (R 2 > 0.9965) over the range of 0.5−50 μg/L, with low limits of detection and quantification in the range of 0.33−0.38 and 1.00−1.25 μg/L, respectively. Intra‐ and interday precisions evaluated by relative standard deviation were 3−6 and 1−6%, respectively. The spiked recoveries of dichlorodiphenyltrichloroethane and its main metabolites from real water samples were in the range of 64−113 and 79−112%, respectively, at two different concentration levels. The results suggest that “frozen” ionic liquids are promising for use as a class of novel sorbents. 相似文献
14.
Sarah Sanjuan Yvette Tran 《Journal of polymer science. Part A, Polymer chemistry》2008,46(13):4305-4319
We report the synthesis of random polyampholyte brushes containing 2‐(dimethylamino)ethyl methacrylate (DMAEMA) and methacrylic acid (MAA). The preparation of polyampholyte brushes is performed by the “grafting from” strategy using surface‐initiated atom transfer radical polymerization (ATRP). The first step consists in the formation of the self‐assembled monolayer of the ATRP initiator. Secondly, the chains are grown from the surface by controlled/“living” radical polymerization. The random copolymer brushes and the corresponding homopolymers brushes containing 2‐(dimethylamino)ethyl methacrylate and tert‐butyl methacrylate (tBuMA) are prepared. The last step is the deprotection of the tBuMA form to the MAA segment by in situ hydrolysis reaction. The annealed DMAEMA group can also be converted to the quenched form by in situ quaternization reaction. This results in the formation of “annealed” and “semiannealed” polyampholyte brushes. The “annealed” polyampholyte corresponds to the random copolymer that contains only annealed units, weak acid and weak base. The “semiannealed” polyampholyte consists of the mixture of annealed (weak acid) and quenched (quaternized segment) units. Polyampholyte brushes with various grafting densities are synthesized and carefully characterized using surface techniques such as ellipsometry and FTIR‐ATR. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 4305–4319, 2008 相似文献
15.
Weipu Zhu Ying Wang Qiujin Zhang Zhiquan Shen 《Journal of polymer science. Part A, Polymer chemistry》2011,49(22):4886-4893
Novel biodegradable amphiphilic graft copolymers containing hydrophobic poly(ester‐carbonate) backbone and hydrophilic poly(ethylene glycol) (PEG) side chains were synthesized by a combination of ring‐opening polymerization and “click” chemistry. First, the ring‐opening copolymerization of 5,5‐dibromomethyl trimethylene carbonate (DBTC) and ε‐caprolactone (CL) was performed in the presence of stannous octanoate [Sn(Oct)2] as catalyst, resulting in poly(DBTC‐co‐CL) with pendant bromo groups. Then the pendant bromo groups were completely converted into azide form, which permitted “click” reaction with alkyne‐terminated PEG by Huisgen 1,3‐dipolar cycloadditions to give amphiphilic biodegradable graft copolymers. The graft copolymers were characterized by proton nuclear magnetic resonance (1H NMR), Fourier transform infrared spectra and gel permeation chromatography measurements, which confirmed the well‐defined graft architecture. These copolymers could self‐assemble into micelles in aqueous solution. The size and morphologies of the copolymer micelles were measured by transmission electron microscopy and dynamic light scattering, which are influenced by the length of PEG and grafting density. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011. 相似文献
16.
Generation of Pseudocontact Shifts in Proteins with Lanthanides Using Small “Clickable” Nitrilotriacetic Acid and Iminodiacetic Acid Tags 下载免费PDF全文
Dr. Choy‐Theng Loh Dr. Bim Graham Elwy H. Abdelkader Dr. Kellie L. Tuck Prof. Gottfried Otting 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(13):5084-5092
Pseudocontact shifts (PCS) induced by paramagnetic lanthanide ions provide unique long‐range structural information in nuclear magnetic resonance (NMR) spectra, but the site‐specific attachment of lanthanide tags to proteins remains a challenge. Here we incorporated p‐azido‐phenylalanine (AzF) site‐specifically into the proteins ubiquitin and GB1, and ligated the AzF residue with alkyne derivatives of small nitrilotriacetic acid and iminodiacetic acid tags using the CuI‐catalysed “click” reaction. These tags form lanthanide complexes with no or only a small net charge and produced sizeable PCSs with paramagnetic lanthanide ions in all mutants tested. The PCSs were readily fitted by single magnetic susceptibility anisotropy tensors. Protein precipitation during the click reaction was greatly alleviated by the presence of 150 mM NaCl. 相似文献
17.
Hanns‐Dieter Amberger Hauke Reddmann Christos Apostolidis Basil Kanellakopulos 《无机化学与普通化学杂志》2003,629(1):147-160
Electronic Structures of Highly Symmetrical Compounds of f Elements. 36 [1] Parametric Analysis of the Optical Spectra of an Oriented Tris(hydrotris(1‐pyrazolyl)borato)praseodymium(III) Single Crystal The absorption and luminescence spectra of polycrystalline tris(hydrotris(1‐pyrazolyl)borato)‐praseodymium(III) (PrTp3) were measured at room temperature as well as at low temperatures. At room temperature the “polarized” luminescence spectra of a small oriented PrTp3 single crystal could also be recorded. On the basis of these spectroscopic findings the underlying crystal field splitting pattern could be derived, and simulated by fitting the free parameters of a phenomenological Hamiltonian, achieving a reduced r.m.s. deviation of 17.3 cm—1 for 37 assignments. On the basis of the parameters used, the global ligand field strength experienced by the Pr3+ central ion as well as the individual ligand field strength associated with one Tp ligand are determined, nephelauxetic and relativistic nephelauxetic effects are estimated, and the experimentally orientiented nonrelativistic and relativistic molecular orbital schemes in the f range are set up. 相似文献
18.
Behrouz Shaabani Prof. Dr. Babak Mirtamizdoust Davide Viterbo Gianluca Croce Hassan Hammud 《无机化学与普通化学杂志》2010,636(8):1596-1600
. A novel 1D PbII coordination polymer [Pb(dmp)I2]n ( 1 ) (dmp = 2,9‐dimethyl‐1,10‐phenanthroline) containing a Pb2‐(μ‐I)2 unit was synthesized and characterized by elemental analysis, IR, 1H NMR, and 13C NMR spectroscopy and studied by thermal analysis as well as X‐ray crystallography. The single‐crystal X‐ray data show that the coordination number of PbII ions is six, i.e. PbN2I4, with “stereo‐chemically active” electron lone pairs, and the coordination sphere is asymmetrical. They also show that the chains interact with each other through π‐π stacking interactions, which create a 3D framework. The structure of the title complex has been optimized by density functional theory calculations. The calculated structural parameters and the IR spectra of the title complex are in agreement with the crystal structure. 相似文献
19.
Chiroptical Detection of Nonchromophoric,Achiral Guests by Enantiopure Alleno‐Acetylenic Helicages 下载免费PDF全文
Dr. Ori Gidron Dr. Marc‐Olivier Ebert Dr. Nils Trapp Prof. Dr. François Diederich 《Angewandte Chemie (International ed. in English)》2014,53(49):13614-13618
Enantiopure alleno‐acetylenic ligands assemble diastereoselectively upon the addition of a zinc(II) salt to form triple‐stranded helicates, which provide a sufficiently large helical cage (“helicage”) for the encapsulation of guests. The inclusion complexation of heteroalicycles is confirmed by ROESY and DOSY NMR spectroscopy and quantified in 1H NMR binding titrations. The ECD spectra of the helicates, which showed strong Cotton effects and exciton coupling, were found to be extremely sensitive to the nature of the guest molecules. Consequently, a series of nonchromophoric, achiral guests of different sizes as well as regioisomers (1,3‐ and 1,4‐dioxane) became distinguishable on the basis of their induced CD (ICD) spectra. Molecular dynamics (MD) simulations show the adaptability of the cavity size to individual guest molecules and support the selective ICD output. Particularly high affinity towards 1,4‐dioxane allowed its selective detection at parts‐per‐million (ppm) levels in aqueous solutions. 相似文献
20.
Spatially Selective Heteronuclear Multiple‐Quantum Coherence Spectroscopy for Biomolecular NMR Studies 下载免费PDF全文
Dr. Bharathwaj Sathyamoorthy Dr. David M. Parish Prof. Gaetano T. Montelione Dr. Rong Xiao Prof. Thomas Szyperski 《Chemphyschem》2014,15(9):1872-1879
Spatially selective heteronuclear multiple‐quantum coherence (SS HMQC) NMR spectroscopy is developed for solution studies of proteins. Due to “time‐staggered” acquisitioning of free induction decays (FIDs) in different slices, SS HMQC allows one to use long delays for longitudinal nuclear spin relaxation at high repetition rates. To also achieve high intrinsic sensitivity, SS HMQC is implemented by combining a single spatially selective 1H excitation pulse with nonselective 1H 180° pulses. High‐quality spectra were obtained within 66 s for a 7.6 kDa uniformly 13C,15N‐labeled protein, and within 45 and 90 s for, respectively, two proteins with molecular weights of 7.5 and 43 kDa, which were uniformly 2H,13C,15N‐labeled, except for having protonated methyl groups of isoleucine, leucine and valine residues. 相似文献