- Preparation of ABC triblock copolymers of N-alkyl substituted acrylamides by RAFT polymerization
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Reversible addition-fragmentation chain transfer (RAFT) polymerization of N-alkyl substituted acrylamides has been carried out by the use of a trithiocarbonate (2-dodecylsulfanylthiocarbonyl-sulfanyl-2-methyl propionic acid) as the RAFT reagent. The N-alkyl groups of the acrylamide monomers are important in the RAFT process. N-alkyl monosubstituted Polyacrylamides are found to be active macro-chain transfer agents, while N,N-disubstituted monomers can react easily with them to form a sequent block. We have designed a synthetic pathway to successfully prepare ABC triblock copolymers of N-alkyl substituted acrylamides with low polydispersities (PDI 1.20) by a three-step RAFT polymerization process.
- Cao, Ya,Zhu
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- Hydrophilic cholesterol-binding molecular imprinted polymers
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Novel hydrophilic molecularly imprinted polymers (MIPs) were prepared using acryloyl-containing hydrophilic monomers (including cholesteryl acrylate (CA) and acryloyl-6-amino-6-deoxy-β (or γ)-cyclodextrin), and their steroid-binding properties were analyzed in 2-PrOH by HPLC. The MIPs bound 38-50 μmol of cholesterol/g, while the corresponding nonimprinted control polymers (containing no CA) bound only 6-9 μmol cholesterol/g. The sterol-binding selectivity was illustrated with estrone, which was bound by MIPs in the range 5-36 μmol/g.
- Zhong, Ning,Byun, Hoe-Sup,Bittman, Robert
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- Linearly thermoresponsive core-shell microgels: Towards a new class of nanoactuators
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In this study we present novel core-shell microgels, with a shell made of poly(N-n-propylacrylamide) (pNNPAM) and a core consisting of poly(N-iso-propylmethacrylamide) (pNIPMAM), exhibiting a unique linear temperature response. The effect is produced by the large LCST gap of 23°C between the shell- and the core-forming polymer. We demonstrate that the shell exhibits a temperature induced de-swelling process that is almost independent of the swelling properties of the core. Furthermore the active collapse of the shell forces a collapse of the core (which is known as the so-called "corset-effect"). In a region between 25°C and 41°C the response of the particles is directly proportional to the temperature. Moreover, the core properties were systematically varied, revealing the possibility to linearly change the magnitude of the linear swelling. Hence, these particles are very promising as piezo-like linear nano-actuators.
- Zeiser, Michael,Freudensprung, Ines,Hellweg, Thomas
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- A cross-metathesis approach to novel pantothenamide derivatives
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Pantothenamides are known for their in vitro antimicrobial activity. Our group has previously reported a new stereoselective route to access derivatives modified at the geminal dimethyl moiety. This route however fails in the addition of large substituents. Here we report a new synthetic route that exploits the known allyl derivative, allowing for the installation of larger groups via cross-metathesis. The method was applied in the synthesis of a new pantothenamide with improved stability in human blood.
- Guan, Jinming,Hachey, Matthew,Puri, Lekha,Howieson, Vanessa,Saliba, Kevin J.,Auclair, Karine
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supporting information
p. 963 - 968
(2016/07/06)
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- STABLE MICELLES FORMED WITH DIBLOCK COPOLYMERS OF CRITICAL MICELLE CONCENTRATION COPOLYMER AND TEMPERATURE-SENSITIVE COPOLYMER
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A novel class of mixed micelles formed with critical micelle concentration (Cmc) character's diblock copolymer, and temperature-sensitive character's diblock copolymer were disclosed. The mixed micelles possess complementary effects in adjusting external temperature shift (storage vs. body temperature) and concentration change (dilution after intravenous injection). The mixed micelles of the present invention can serve as a potential injectable drug delivery system for anticancer drugs, such as doxorubicin and many others.
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- Synthesis and evaluation of peptidic irreversible inhibitors of tissue transglutaminase
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Herein we report the synthesis and the evaluation of eight novel compounds as irreversible inhibitors of transglutaminase (TGase). These compounds are based on a minimal peptidic scaffold shown previously [Chem. Biol. 2005, 12, 469-475] to confer affinity for the TGase active site and bear electrophilic groups such as α,β-unsaturated amide, chloroacetamide or maleimide; their general structure being Cbz-Phe-spacer-electrophile. The affinity conferred by the Cbz-Phe scaffold was determined by comparison to N-propylacrylamide and the length of the spacer was also varied to evaluate its importance. The inhibitory efficiencies (kinact/KI) of these compounds vary up to 105 M-1 min-1, among the highest reported for derivatives based on this simple Cbz-Phe peptidic scaffold.
- Pardin, Christophe,Gillet, Steve M.F.G.,Keillor, Jeffrey W.
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p. 8379 - 8385
(2008/02/05)
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- New 4-arylpiperidine derivatives for the treatment of pruritus
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There is provided a compound of formula I, wherein Het1, R1, R2, R3, X and n have meanings given in the description, which are useful in the prophylaxis and in the treatment of diseases mediated by opiate receptors, such as pruritus.
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- 4-arylpiperidine derivatives for the treatment of pruritus
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There is provided a compound of formula I, wherein Het1, R1, R2, R3, X and n have meanings given in the description, which are useful in the prophylaxis and in the treatment of diseases mediated by opiate receptors, such as pruritus.
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- Development of a second generation coenzyme a analogue synthon
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We have previously reported a general synthetic approach to analogues of coenzyme A (CoA) which involves enzymatic synthesis of a general CoA analogue synthon having a thioester linkage in place of the amide bond nearest the thiol group (Martin et al. J. Am. Chem. Soc. 1994, 116, 4660). We report here the synthesis of a second CoA analogue synthon 1c which has the amide bond more distant from the thiol group replaced with a thioester. This analogue was prepared by nonenzymatic synthesis of a racemic phosphopantetheine analogue followed by enzymatic conversion to the corresponding CoA analogue. Stereochemical analysis showed that the natural enantiomer of the phosphopantetheine analogue was selectively converted to product by the enzyme phosphopantetheine adenylyltansferase, yielding a product that possessed the desired stereoconfiguration. Reaction of the new synthon 1c with a primary amine results in amide bond formation to form the CoA analogue of interest. This new methodology provides access to an even broader array of CoA analogues modified in the β-alanylcysteamine moiety. This has been demonstrated in the synthesis of an analogue having an extra methylene group in the β-alanine moiety and two analogues in which the amide bond nearest the thiol group is replaced with a pair of methylene groups.
- Bibart, Richard T.,Vogel, Kurt W.,Drueckhammer, Dale G.
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p. 2903 - 2909
(2007/10/03)
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- Process for the production of N-substituted α,β-unsaturated carboxylic acid amides
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The present invention relates to a process for the production of N-substituted α,β-unsaturated carboxylic acid amides, which proceeds from the α,β-unsaturated carboxylic acid amide that is unsubstituted at the amido nitrogen, which forms the Michael adduct initially by conversion with a polyvalent alcohol having a boiling point of >/=150° C., converts this with a primary or secondary amine with elimination of ammonia to form N-substituted carboxylic acid amide with a protected double bond, the polyvalent alcohol being subsequently eliminated from this product at high temperatures, with formation of the N-substituted α,β-unsaturated carboxylic acid amide.
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- Process for the production of N-substituted acrylic acid amides
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The present invention relates to a process for the production of N-substituted acrylic acid amides by conversion of 2-carboalkoxy-t-oxabicyclo(2,2,1)hept-5-enes with primary or secondary amines to 2-carboxamide-7-oxabicyclo(2,2,1)hept-5-enes and the thermal decomposition of the latter, preferably in the presence of Lewis acids and in a vacuum, to furane and N-substituted acrylic acid amides. The process according to the invention results in high purity N-substituted acrylic acid amides that are, in the main, free of bifunctional monomers which would disrupt the subsequent polymerization of the N-substituted acrylic acid amides by undesired cross-linking.
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