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Towards Sequence‐Controlled Antimicrobial Polymers: Effect of Polymer Block Order on Antimicrobial Activity
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Peter R. Judzewitsch Dr. Thuy‐Khanh Nguyen Dr. Sivaprakash Shanmugam Dr. Edgar H. H. Wong Prof. Cyrille Boyer 《Angewandte Chemie (International ed. in English)》2018,57(17):4559-4564
Synthetic polymers have shown promise in combating multidrug‐resistant bacteria. However, the biological effects of sequence control in synthetic antimicrobial polymers are currently not well understood. As such, we investigate the antimicrobial effects of monomer distribution within linear high‐order quasi‐block copolymers consisting of aminoethyl, phenylethyl, and hydroxyethyl acrylamides made in a one‐pot synthesis approach via photoinduced electron transfer–reversible addition–fragmentation chain transfer polymerisation (PET‐RAFT). Through different combinations of monomer/polymer block order, antimicrobial and haemolytic activities are tuneable in a manner comparable to antimicrobial peptides. 相似文献
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Ryohei Kakuchi Mirela Zamfir Jean‐Franois Lutz Patrick Theato 《Macromolecular rapid communications》2012,33(1):54-60
The successful sequence‐controlled installation of an activated ester using a newly designed monomer pentafluorophenyl 4‐maleimidobenzoate is demonstrated. Pentafluorophenyl 4‐maleimidobenzoate is kinetically installed at different stages of a nitroxide‐mediated polymerization, namely, near the α‐chain end and in the middle of a PS chain. In addition, successful installation of apolar and polar functional groups is achieved via post‐polymerization functionalization, which demonstrated the versatility of the synthesis of a universal precursor for locally functionalized polymers. 相似文献
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ZHOU ZhiPing Jia ZhengWei & YAN DeYue School of Materials Science Engineering Jiangsu University Zhenjiang China State Key Laboratory of Metal Matrix Composites Shanghai Jiao Tong University Shanghai 《中国科学:化学》2010,(4)
This study develops the kinetics for the slow monomer addition technique in the synthesis of hyperbranched polymers. Taking the conversion of monomer (x) as a variable, we derived the analytic expressions of molecular size distribution function, average degree of polymerization, polydispersity index and degree of branching. These expressions are not only amenable to the polymerization with high monomer conversion, but also appropriate to describe the whole polymerization process. Comparison with the one-pot... 相似文献
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Synthetic approaches which allow to insert rather long fragments with exactly definite sequence of several single structural units into polymer chains are considered and summarized. The procedure consists in preliminary formation of such sequences in a form of bifunctional “complex monomer” (synthons) which may undergo a polycondensation with other single or complex monomer to form macromolecule with definite alternation of several single monomers. These synthetic approaches were used for the synthesis of LC multi-block copolymers with definite structure of rigid block. 相似文献
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Ken‐Ichi Seno Itsuko Tsujimoto Shokyoku Kanaoka Sadahito Aoshima 《Journal of polymer science. Part A, Polymer chemistry》2008,46(19):6444-6454
Stimuli‐responsive gradient copolymers, composed of various monomers, were synthesized by living cationic polymerization in the presence of base. The monomers included thermosensitive 2‐ethoxyethyl vinyl ether (EOVE) and 2‐methoxyethyl vinyl ether (MOVE), hydrophobic isobutyl vinyl ether (IBVE) and 2‐phenoxyethyl vinyl ether (PhOVE), crystalline octadecyl vinyl ether (ODVE), and hydrophilic 2‐hydroxyethyl vinyl ether (HOVE). The synthesis of gradient copolymers was conducted using a semibatch reaction method. Living cationic polymerization of the first monomer was initiated using a conventional syringe technique, followed by an immediate and continuous addition of a second monomer using a syringe pump at regulated feed rates. This simple method permitted precise control of the sequence distribution of gradient copolymers, even for a pair of monomers with very different relative monomer reactivities. The stimuli‐responsive gradient, block and random copolymers exhibited different self‐association behavior. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 6444–6454, 2008 相似文献
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Yuuki Inoue Junji Watanabe Madoka Takai Shin‐ichi Yusa Kazuhiko Ishihara 《Journal of polymer science. Part A, Polymer chemistry》2005,43(23):6073-6083
A series of copolymers composed of two monomer units having a polar phosphorylcholine group and an apolar fluorocarbon group with a controlled monomer unit sequence were synthesized by a reversible addition‐fragmentation chain transfer (RAFT) living radical polymerization method. 2‐Methacryloyloxyethyl phosphorylcholine (MPC) and 2,2,2‐trifluoroethyl methacrylate (TFEMA) were selected as the monomers, because they have disparate polarity. Furthermore, to investigate the influence of the monomer unit sequence in a polymer chain on the phase‐separated structure in the bulk and surface structure, copolymers having a continuous change in the monomer unit composition along the polymer chain (gradient copolymer) were synthesized, as well as random and block copolymers. The analysis of instantaneous composition revealed a continuous change in the monomer unit composition in the gradient copolymer and the statistical monomer unit sequence in the random copolymer. Thermal analysis assumed that the gradient sequence of the monomer unit would make the phase‐separated structure in the bulk ambiguous, while the well‐defined and monodispersive block sequence would undergo the distinct phase‐separation due to the extreme difference in the polarity of the component monomer units. The preliminary surface characterization of the synthesized polymers indicated the monomer unit sequence in the polymer chain would much influence on the surface structure. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 6073–6083, 2005 相似文献
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R. Nicholas Carmean C. Adrian Figg Troy E. Becker Prof. Brent S. Sumerlin 《Angewandte Chemie (International ed. in English)》2016,55(30):8624-8629
A biphasic one‐pot polymerization method enables the preparation of block copolymers from monomers with similar and competitive reactivities without the addition of external materials. AB diblock copolymers were prepared by encapsulating a frozen solution of monomer B on the bottom of a reaction vessel, while the solution polymerization of monomer A was conducted in a liquid layer above. Physical separation between the solid and liquid phases permitted only homopolymerization of monomer A until heating above the melting point of the lower phase, which released monomer B, allowing the addition of the second block to occur. The triggered release of monomer B allowed for chain extension without additional deoxygenation steps or exogenous monomer addition. A method for the closed (i.e., without addition of external reagents) one‐pot synthesis of block copolymers with conventional glassware using straightforward experimental techniques has thus been developed. 相似文献
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Shigeru Yabumoto Kiyoshi Ishii Koichiro Arita 《Journal of polymer science. Part A, Polymer chemistry》1969,7(7):1577-1588
Copolymerization of acrylonitrile with styrene spontaneously occurred on addition of zinc chloride without addition of any other radical initiator. The composition of the copolymer approached that of strictly alternating copolymer as zinc chloride added to the copolymerization system increased. The significance of the apparent monomer reactivity ratios of this copolymerization system was studied from a kinetic point of view, and it was shown that the monomer sequence distribution is indicated by the apparent monomer reactivity ratios. Further, equations which represent the relation between the apparent monomer reactivity ratios and Q,e values at a given salt concentration were derived. These equations reasonably accounted for the decrease of the apparent monomer reactivity ratios of the copolymerization of acrylonitrile with styrene in the presence of zinc chloride and the behavior of the other acrylonitrile copolymerization systems in the presence of zinc chloride. The initiation step of the spontaneous radical copolymerization of acrylonitrile with styrene in the presence of zinc chloride was explained by a cross-initiation mechanism. 相似文献
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Owen W. Webster 《Macromolecular Symposia》1990,33(1):133-143
The synthesis of polymethacrylates by a repeated silyl Michael addition reaction (GTP)a allows one to control the molecular weight of the polymer by adjusting the monomer/initator ratio. A small amount of cyclic termination occurs but in general low molecular weight dispersity is obtained. Block polymers can be made by sequential addition of monomer. Functionality present on the ketene acetal portion of the initiator will be on one end of each polymer chain. Star polymers result from crosslinking active polymer with a bismethacrylate. Initiation of bismethacrylate with bisinitiator gives a ladder polymer. 相似文献
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Jong-Wu Chen Leo-Wang Chen 《Journal of polymer science. Part A, Polymer chemistry》1999,37(12):1797-1803
This research discussed the effect of the addition of antimony catalyst on diethylene glycol (DEG) formation in poly(ethylene terephthalate) (PET) synthesis. It was found that antimony catalyst increased DEG formation in the preparation of PET, in particular, during the esterification stage and also during the prepolycondensation stage. To further discuss the effect of antimony catalyst on DEG formation in the preparation of PET, this research also focused on the kinetics of DEG formation during PET synthesis from purified bishydroxyethyl terephthalate (BHET) monomer with antimony catalyst. The rate expression of DEG formation from BHET monomer and antimony catalyst was described. It was found that the activation energy of BHET monomer with antimony catalyst in DEG formation is lower than that of BHET monomer without the addition of catalyst. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 1797–1803, 1999 相似文献
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[Structure: see text] The total synthesis of the marine diolide (-)-clavosolide A has been achieved in 17 steps (longest linear sequence) from commercially available crotonaldehyde exploiting the Petasis-Ferrier union/rearrangement tactic to construct the requisite aglycon monomer. A one-pot esterification/lactonization employing the Yamaguchi protocol, followed by bis-glycosidation, furnished (-)-clavosolide A. 相似文献
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Yuki Kametani Dr. François Tournilhac Prof. Dr. Mitsuo Sawamoto Prof. Dr. Makoto Ouchi 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(13):5231-5239
Herein, we report a method to synthesize a series of alternating copolymers that consist exclusively of acrylamide units. Crucial to realizing this polymer synthesis is the design of a divinyl monomer that contains acrylate and acrylamide moieties connected by two activated ester bonds. This design, which is based on the reactivity ratio of the embedded vinyl groups, allows a “selective” cyclopolymerization, wherein the intramolecular and intermolecular propagation are repeated alternately under dilute conditions. The addition of an amine to the resulting cyclopolymers afforded two different acryl amide units, i.e., an amine-substituted acryl amide and a 2-hydroxy-ethyl-substituted acryl amide in alternating sequence. Using this method, we could furnish ten types of alternating copolymers; some of these exhibit unique properties in solution and in the bulk, which are different from those of the corresponding random copolymers, and we attributed the differences to the alternating sequence. 相似文献
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Replication of sequence information with mutation is the molecular basis for the evolution of functional biopolymers. Covalent template-directed synthesis has been used to replicate sequence information in synthetic oligomers, and the covalent base-pairs used in these systems provide an opportunity to manipulate the outcome of the information transfer process through the use of traceless linkers. Two new types of covalent base-pair have been used to introduce mutation in the replication of an oligotriazole, where information is encoded as the sequence of benzoic acid and phenol monomer units. When a benzoic acid–benzoic acid base-pairing system was used, a direct copy of a benzoic acid homo-oligomer template was obtained. When a phenol–benzoic acid base-pairing system was used, a reciprocal copy, the phenol homo-oligomer, was obtained. The two base-pairing systems are isosteric, so they can be used interchangeably, allowing direct and reciprocal copying to take place simultaneously on the same template strand. As a result, it was possible to introduce mutations in the replication process by spiking the monomer used for direct copying with the monomer used for reciprocal copying. The mutation rate is determined precisely by the relative proportions of the two monomers. The ability to introduce mutation at a controlled rate is a key step in the development of synthetic systems capable of evolution, which requires replication with variation.The use of two different covalent base-pairs introduces sequence mutations at a controlled rate in the covalent template-directed synthesis of oligotriazoles, a step towards evolvable synthetic polymers. 相似文献
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Susanne C. Solleder Deniz Zengel Katharina S. Wetzel Prof. Dr. Michael A. R. Meier 《Angewandte Chemie (International ed. in English)》2016,55(3):1204-1207
The efficient synthesis of a sequence‐defined decamer, its characterization, and its straightforward dimerization through self‐metathesis are described. For this purpose, a monoprotected AB monomer was designed and used to synthesize a decamer bearing ten different and selectable side chains by iterative Passerini three‐component reaction (P‐3CR) and subsequent deprotection. The highly efficient procedure provided excellent yields and allows for the multigram‐scale synthesis of such perfectly defined macromolecules. An olefin was introduced at the end of the synthesis, allowing the self‐metathesis reaction of the resulting decamer to provide a sequence‐defined 20‐mer with a molecular weight of 7046.40 g mol?1. The obtained oligomers were carefully characterized by NMR and IR spectroscopy, GPC and GPC coupled to ESI‐MS, and mass spectrometry (FAB and orbitrap ESI‐MS). 相似文献
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Bodlenner A Alix A Weibel JM Pale P Ennifar E Paillart JC Walter P Marquet R Dumas P 《Organic letters》2007,9(22):4415-4418
A neamine dimer designed to bind to a specific sequence of HIV-1 RNA has been synthesized. Starting from neomycin B (1), a five-step synthesis efficiently provided a key protected neamine monomer 6 (28%). From the latter, coupling reactions with activated diacids gave dimers. After deprotection, a neamine dimer was obtained as the hexachlorohydrate salt 15 with 13% overall yield over nine steps. 相似文献
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Yi Wan Dr. Jianghua He Dr. Yuetao Zhang 《Angewandte Chemie (International ed. in English)》2023,62(8):e202218248
Rapid access to sequence-controlled multi-block copolymers (multi-BCPs) remains as a challenging task in the polymer synthesis. Here we employ a Lewis pair (LP) composed of organophosphorus superbase and bulky organoaluminum to effectively copolymerize the mixture of methacrylate, cyclic acrylate, and two acrylates, into well-defined di-, tri-, tetra- and even a hepta-BCP in one-pot one-step manner. The combined livingness, dual-initiation and CSC feature of Lewis pair polymerization enable us to achieve not only a trihexaconta-BCP with the highest record in 8 steps by using four-component monomer mixture as building blocks, but also the arbitrarily-regulated monomer sequence in multi-BCP, simply by changing the composition and adding order of the monomer mixtures, thus demonstrating the powerful capability of our strategy in improving the efficiency and enriching the composition of multi-BCP synthesis. 相似文献
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Tomohiro Kubo Morgan S. Young Kendra D. Souther Matthew D. Hannigan Anne J. McNeil 《Journal of polymer science. Part A, Polymer chemistry》2021,59(3):268-273
The discovery of catalyst-transfer polymerization and its further developments have led to unprecedented control over the length and sequence of conjugated polymers. However, the methods themselves are technically challenging to perform due to the air- and moisture-sensitivities of the monomers and catalysts. Herein, we report a catalyst-transfer polymerization method that affords poly(3-hexylthiophene) in high yields without using an inert atmosphere. The synthesis capitalizes on a rapid Negishi cross-coupling using a moisture-tolerant organozinc monomer mediated by an air-stable Pd precatalyst. This simple method should make conjugated polymer synthesis more accessible to a broader range of researchers and may be generalizable to other monomer scaffolds. 相似文献