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Dr. Yu Kitazawa Mamoru Watanabe Yui Masumoto Mai Otsuka Dr. Kazunori Miyamoto Dr. Atsuya Muranaka Dr. Daisuke Hashizume Dr. Ryo Takita Prof. Dr. Masanobu Uchiyama 《Angewandte Chemie (International ed. in English)》2018,57(6):1501-1504
We designed, synthesized, and characterized two types of dimeric forms of monocarba‐closo‐dodecaborate, namely, a “dumbbell”‐shaped dianion having a C?C bond and a “clackers”‐shaped monoanion having an iodonium linker. The unique architectures of these anionic molecules were established by X‐ray analysis. Spectroscopic analysis, DFT calculations, and reactivity experiments revealed high anionic and chemical stability of both anions, which are crucial properties for weakly coordinating anions. 相似文献
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Erik Schwartz Vincenzo Palermo Dr. Chris E. Finlayson Dr. Ya‐Shih Huang Matthijs B. J. Otten Andrea Liscio Dr. Sara Trapani Irene González‐Valls Patrick Brocorens Dr. Jeroen J. L. M. Cornelissen Dr. Kalina Peneva Dr. Klaus Müllen Prof. Dr. Frank C. Spano Prof. Dr. Arkady Yartsev Prof. Sebastian Westenhoff Dr. Richard H. Friend Prof. Dr. David Beljonne Dr. Roeland J. M. Nolte Prof. Dr. Paolo Samorì Prof. Dr. Alan E. Rowan Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(11):2536-2547
Exciton migration! Spectroscopic analyses and extensive molecular dynamics studies revealed a well‐defined 41 helix in which the perylene molecules (see figure) form four “helter‐skelter‐like” overlapping pathways along which excitons and electrons can rapidly migrate.
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Self‐Assembly of Chiral Propeller‐like Supermolecules with Unusual “Sergeants‐and‐Soldiers” and “Majority‐Rules” Effects 下载免费PDF全文
Bo Nie Tian‐Guang Zhan Tian‐You Zhou Dr. Ze‐Yun Xiao Prof. Guo‐Fang Jiang Prof. Xin Zhao 《化学:亚洲杂志》2014,9(3):754-758
Chiral amplification is an interesting phenomenon in supramolecular chemistry mainly observed in complicated systems in which cooperative effect dominate. Herein, chiral, supramolecular, propeller‐like architectures have been constructed through coassembly of an achiral disk‐shaped molecule and chiral amino acid derivatives driven by intermolecular hydrogen bonding. Both the “sergeants‐and‐soldiers” principle and “majority‐rules” effect are applicable in these discrete four‐component supermolecules, which are the simplest supramolecular system ever reported that exhibit chiral amplification. 相似文献
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“Head‐to‐Middle” and “Head‐to‐Tail” cis‐Prenyl Transferases: Structure of Isosesquilavandulyl Diphosphate Synthase 下载免费PDF全文
Jian Gao Dr. Tzu‐Ping Ko Lu Chen Dr. Satish R. Malwal Jianan Zhang Xiangying Hu Fiona Qu Dr. Weidong Liu Dr. Jian‐Wen Huang Dr. Ya‐Shan Cheng Dr. Chun‐Chi Chen Yunyun Yang Prof. Dr. Yonghui Zhang Prof. Dr. Eric Oldfield Prof. Dr. Rey‐Ting Guo 《Angewandte Chemie (International ed. in English)》2018,57(3):683-687
We report the first X‐ray crystallographic structure of the “head‐to‐middle” prenyltransferase, isosesquilavandulyl diphosphate synthase, involved in biosynthesis of the merochlorin class of antibiotics. The protein adopts the ζ or cis‐prenyl transferase fold but remarkably, unlike tuberculosinol adenosine synthase and other cis‐prenyl transferases (e.g. cis‐farnesyl, decaprenyl, undecaprenyl diphosphate synthases), the large, hydrophobic side chain does not occupy a central hydrophobic tunnel. Instead, it occupies a surface pocket oriented at 90° to the hydrophobic tunnel. Product chain‐length control is achieved by squeezing out the ligand from the conventional allylic S1 binding site, with proton abstraction being achieved using a diphosphate‐Asn‐Ser relay. The structures revise and unify our thinking as to the mechanism of action of many other prenyl transferases and may also be of use in engineering new merochlorin‐class antibiotics. 相似文献
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Prof. José Barluenga Dr. Agustín Jiménez‐Aquino Prof. Fernando Aznar Dr. Carlos Valdés 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(38):11707-11711
Regioselectively substituted indoles are prepared by a Pd‐catalyzed C? C/C? N bond‐forming sequence from imines and o‐dihaloarenes or o‐haloarene sulfonates. The heterogeneous reaction as a suspension in water and under microwave heating offers important advantages in comparison with the conventional reaction in an organic solvent, among them, operational simplicity, the employment of KOH solutions instead of alkoxides, and a dramatic reduction of reaction times. 相似文献
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An “Ingredients” Approach to Functional Self‐Synthesizing Materials: A Metal‐Ion‐Selective,Multi‐Responsive,Self‐Assembled Hydrogel 下载免费PDF全文
Dr. Jianwei Li Ivica Cvrtila Mathieu Colomb‐Delsuc Dr. Edwin Otten Prof. Dr. Sijbren Otto 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(48):15709-15714
New methodology for making novel materials is highly desirable. Here, an “ingredients” approach to functional self‐assembled hydrogels was developed. By designing a building block to contain the right ingredients, a multi‐responsive, self‐assembled hydrogel was obtained through a process of template‐induced self‐synthesis in a dynamic combinatorial library. The system can be switched between gel and solution by light, redox reactions, pH, temperature, mechanical energy and sequestration or addition of MgII salt. 相似文献
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Stoichiometrically Controlled Revocable Self‐Assembled “Spiro” versus Quadruple‐Stranded “Double‐Decker” Type Coordination Cages 下载免费PDF全文
Sreenivasulu Bandi Dr. Amlan K. Pal Prof. Dr. Garry S. Hanan Prof. Dr. Dillip Kumar Chand 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(41):13122-13126
The simple combination of PdII with the tris‐monodentate ligand bis(pyridin‐3‐ylmethyl) pyridine‐3,5‐dicarboxylate, L , at ratios of 1:2 and 3:4 demonstrated the stoichiometrically controlled exclusive formation of the “spiro‐type” Pd1L2 macrocycle, 1 , and the quadruple‐stranded Pd3L4 cage, 2 , respectively. The architecture of 2 is elaborated with two compartments that can accommodate two units of fluoride, chloride, or bromide ions, one in each of the enclosures. However, the entry of iodide is altogether restricted. Complexes 1 and 2 are interconvertible under suitable conditions. 相似文献
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Dr. Guillaume Bort Dr. Thibault Gallavardin Dr. David Ogden Dr. Peter I. Dalko 《Angewandte Chemie (International ed. in English)》2013,52(17):4526-4537
Molecular systems that can be remotely controlled by light are gaining increasing importance in cell biology, physiology, and neurosciences because of the spatial and temporal precision that is achievable with laser microscopy. Two‐photon excitation has significant advantages deep in biological tissues, but raises problems in the design of “smart” probes compatible with cell physiology. This Review discusses the chemical challenges in generating suitable two‐photon probes. 相似文献
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Kai Zhang Ying Wang Weipu Zhu Xiaodong Li Zhiquan Shen 《Journal of polymer science. Part A, Polymer chemistry》2012,50(10):2045-2052
Biodegradable and biocompatible PCL‐g‐PEG amphiphilic graft copolymers were prepared by combination of ROP and “click” chemistry via “graft onto” method under mild conditions. First, chloro‐functionalized poly(ε‐caprolactone) (PCL‐Cl) was synthesized by the ring‐opening copolymerization of ε‐caprolactone (CL) and α‐chloro‐ε‐caprolactone (CCL) employing scandium triflate as high‐efficient catalyst with near 100% monomer conversion. Second, the chloro groups of PCL‐Cl were quantitatively converted into azide form by NaN3. Finally, copper(I)‐catalyzed cycloaddition reaction was carried out between azide‐functionalized PCL (PCL‐N3) and alkyne‐terminated poly(ethylene glycol) (A‐PEG) to give PCL‐g‐PEG amphiphilic graft copolymers. The composition and the graft architecture of the copolymers were characterized by 1H NMR, FTIR, and GPC analyses. These amphiphilic graft copolymers could self‐assemble into sphere‐like aggregates in aqueous solution with diverse diameters, which decreased with the increasing of grafting density. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012 相似文献
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James V. Crivello 《Journal of polymer science. Part A, Polymer chemistry》2014,52(20):2934-2946
In the presence of small amounts of 2,2‐dialkyl‐, 2,2,3‐trialkyl‐, or 2,2,3,3‐tetraalkyl substituted epoxides such as isobutylene oxide, 1,2‐limonene oxide, and 2,2,3,3,‐tetramethyl oxirane, the photoinitiated cationic ring‐opening polymerizations of 3,3‐disubstituted oxetanes are dramatically accelerated. The acceleration affect was attributed to an increase in the rate of the initiation step of these latter monomers. Both mono‐ and disubstituted oxetane monomers are similarly accelerated by the above‐mentioned epoxides to give crosslinked network polymers. The potential for the use of such “kick‐started” systems in applications such as coatings, adhesives, printing inks, dental composites and in three‐dimensional imaging is discussed. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 2934–2946 相似文献