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101.
Dr. Cheng‐Chung Lee Dr. Manuel Maestre‐Reyna Dr. Kai‐Cheng Hsu Prof. Dr. Hao‐Ching Wang Prof. Dr. Chia‐I Liu Prof. Dr. Wen‐Yih Jeng Li‐Ling Lin Richard Wood Dr. Chia‐Cheng Chou Prof. Dr. Jinn‐Moon Yang Prof. Dr. Andrew H.‐J. Wang 《Angewandte Chemie (International ed. in English)》2014,53(48):13054-13058
Crown ethers are small, cyclic polyethers that have found wide‐spread use in phase‐transfer catalysis and, to a certain degree, in protein chemistry. Crown ethers readily bind metallic and organic cations, including positively charged amino acid side chains. We elucidated the crystal structures of several protein‐crown ether co‐crystals grown in the presence of 18‐crown‐6. We then employed biophysical methods and molecular dynamics simulations to compare these complexes with the corresponding apoproteins and with similar complexes with ring‐shaped low‐molecular‐weight polyethylene glycols. Our studies show that crown ethers can modify protein surface behavior dramatically by stabilizing either intra‐ or intermolecular interactions. Consequently, we propose that crown ethers can be used to modulate a wide variety of protein surface behaviors, such as oligomerization, domain–domain interactions, stabilization in organic solvents, and crystallization. 相似文献
102.
Frontispiece: NMR Fingerprints of the Drug‐like Natural‐Product Space Identify Iotrochotazine A: A Chemical Probe to Study Parkinson’s Disease 下载免费PDF全文
103.
Kyle M. Lambert Joshua B. Cox Lin Liu Amy C. Jackson Sam Yruegas Kenneth B. Wiberg John L. Wood 《Angewandte Chemie (International ed. in English)》2020,59(24):9757-9766
The development of a concise total synthesis of (±)‐phyllantidine ( 1 ), a member of the securinega family of alkaloids containing an unusual oxazabicyclo[3.3.1]nonane core, is described. The synthesis employs a unique synthetic strategy featuring the ring expansion of a substituted cyclopentanone to a cyclic hydroxamic acid as a key step that allows facile installation of the embedded nitrogen‐oxygen (N?O) bond. The optimization of this sequence to effect the desired regiochemical outcome and its mechanistic underpinnings were assessed both computationally and experimentally. This synthetic approach also features an early‐stage diastereoselective aldol reaction to assemble the substituted cyclopentanone, a mild reduction of an amide intermediate without N?O bond cleavage, and the rapid assembly of the butenolide found in ( 1 ) via use of the Bestmann ylide. 相似文献
104.
Jenna M. Allan Md Abdul Mumin Jeffery A. Wood William Z. Xu Wei Wu Paul A. Charpentier 《Journal of Polymer Science.Polymer Physics》2014,52(14):927-935
Poly(ethylene‐co‐vinyl acetate) (EVA) plastic films are widely used for solar coverings including photovoltaic modules and commercial greenhouse films, but are poor at controlling heat flow. In this work, silica aerogel (SA) nanogels were examined for preparing transparent heat retention EVA films that block far infrared spectra radiation to maintain heat, without compromising the optical performance of the films. SA nanogels were melt‐mixed using a mini twin‐screw extruder with EVA pellets to form SA/EVA composite, which were pressed into thin films with controlled thickness. The composite films were characterized in terms of optical properties using a variety of analytical methods including FTIR, UV–Vis spectroscopy, electron, confocal, and atomic force microscopy. Both thermicity and thermal conductivity of commercial and experimental SA/EVA films were measured. The results demonstrated that the SA/EVA films gave improved infrared retention compared to commercial thermal plastic films without compromising visible light transmission, showing the potential for this approach in next generation heat retention films. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2014 , 52, 927–935 相似文献
105.
Stephen K. Taylor Dawn DeYoung Lloyd J. Simons James R. Vyvyan ‡ Mary A. Wemple Noelle K. Wood 《合成通讯》2013,43(9):1691-1701
The nucleophilic opening of epoxides by nitrile enolates using an efficient, convenient protocol is described. The diastereoselectivity of this reaction was explored and found to give syn:anti ratios ranging from 1.1:1.0 to 4.8:1.0. 相似文献
106.
107.
J. L. Pore D. S. Cross C. Andreoiu R. Ashley G. C. Ball P. C. Bender A. S. Chester A. Diaz Varela G. A. Demand R. Dunlop A. B. Garnsworthy P. E. Garrett G. Hackman B. Hadinia B. Jigmeddorj A. T. Laffoley A. Liblong R. Kanungo B. Noakes C. M. Petrache M. M. Rajabali K. Starosta C. E. Svensson P. J. Voss Z. M. Wang J. L. Wood S. W. Yates 《The European Physical Journal A - Hadrons and Nuclei》2017,53(2):27
108.
The structure of linear codes of constant weight 总被引:1,自引:0,他引:1
Jay A. Wood 《Transactions of the American Mathematical Society》2002,354(3):1007-1026
In this paper we determine completely the structure of linear codes over of constant weight. Namely, we determine exactly which modules underlie linear codes of constant weight, and we describe the coordinate functionals involved. The weight functions considered are: Hamming weight, Lee weight, two forms of Euclidean weight, and pre-homogeneous weights. We prove a general uniqueness theorem for virtual linear codes of constant weight. Existence is settled on a case by case basis.
109.
Wood JM Hinchliffe PS Davis AM Austin RP Page MI 《Chemical communications (Cambridge, England)》2002,(7):772-773
The alkaline hydrolysis of N-alpha-methoxycarbonyl benzyl-beta-sultam occurs 10(3) times faster than the corresponding carboxylate and with rapid D-exchange at the alpha-carbon: the pH rate profile indicates pre-equilibirum CH ionisation and together with formation of benzoyl formate as a product this suggests a novel mechanism for hydrolysis. 相似文献
110.