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241.
Jerry E. White Anthony P. Haag R. Garth Pews Shari L. Kram Chester E. Pawloski Charles N. Brown 《Journal of polymer science. Part A, Polymer chemistry》1996,34(14):2967-2973
Base-initiated polymerizations of N,′N-dimethyl-1,3-benzenedisulfonamide or other N,′N-dialkyldisulfonamides with various arylene-diglycidyl ethers afford a broad range of poly(hydroxy ether sulfonamides) (2). Polymers 2, which represent a new family of epoxy-based thermoplastics, are moldable, amorphous materials characterized by moderate Tg (58–127°C) and by good barrier to oxygen, reflected by oxygen transmission rates of 0.45–2.89 cc-mil/100 in2-atm (O2)-day at 234 °C and about 60% relative humidity. In addition to a discussion of how structural changes in the backbones of 2 influence their barrier properties, details of the synthesis, thermal analysis and mechanical evaluation of the polymers are described. © 1996 John Wiley & Sons, Inc. 相似文献
242.
Joseph H. Boyer Anthony M. Haag Govindarao Sathyamoorthi Mou-Ling Soong Kannappan Thangaraj Theodore G. Pavlopoulos 《Heteroatom Chemistry》1993,4(1):39-49
Pyrromethene–BF2 complexes (P–BF2) 7 were obtained from α-unsubstituted pyrroles 5 by acylation and condensation to give intermediate pyrromethene hydrohalides 6 followed by treatment with boron trifluoride etherate. Conversion of ethyl α-pyrrolecarboxylates 4 to α-unsubstituted pyrroles 5 was brought about by thermolysis in phosphoric acid at 160°C, or by saponification followed by decarboxylation in ethanolamine at 180°C, or as unisolated intermediates in the conversion of esters 4 to pyrromethene hydrobromides 6 by heating in a mixture of formic and hydrobromic acids. Addition of hydrogen cyanide followed by dehydrogenation by treatment with bromine converted 3,5,3′,5′-tetramethyl-4,4′-diethylpyrromethene hydrobromide 9 to 3,5,-3′,5′-tetramethyl-4,4′-diethyl-6-cyanopyrromethene hydrobromide 6bb , confirmed by the further conversion to 1,3,5,7-tetramethyl-2,6-diethyl-8-cyanopyrromethene–BF2 complex 7bb on treatment with boron trifluoride etherate. An alternation effect in the relative efficiency (RE) of laser activity in 1,3,5,7,8-pentamethyl-2,6-di-n-alkylpyrromethene–BF2 dyes depended on the number of methylene units in the n-alkyl substituent, -(CH2)nH, to give RE ≥ 100 when n = 0,2,4 and RE 65, 85 when n = 1,3. (The RE 100 was arbitrarily assigned to the dye rhodamine 6G). The absence of fluorescence and laser activity in 1,3,5,7-tetramethyl-2,6-diethyl-8-isopropylpyrromethene–BF2 complex 7p and a markedly diminished fluorescence quantum yield (Φ 0.23) and lack of laser activity in 1,3,5,7-tetramethyl-2,6-diethyl-8-cyclohexylpyrromethene–BF2 complex 7q were attributed to molecular nonplanarity brought about by the steric interference between each of the two bulky 8-substituents with the 1,7-dimethyl substituents. An atypically low RE 20 for a peralkylated dye without steric interference was observed for 1,2,6,7-bistrimethylene-3,5,8-trimethylpyrromethene–BF2 complex 7j . Comparisons with peralkylated dyes revealed a major reduction in RE 0–40 for the six dyes 7u–z lacking substitution at the 8-position. Low laser activity RE was brought about by functional group (polar) substitution in the 2,6-diphenyl derivative 7I , RE 20, and the 2,6-diacetamido derivative 7m , RE 5, of 1,3,5,7,8-pentamethylpyrromethene–BF2 complex (PMP–BF2) 7a and in 1,7-dimethoxy-2,3,5,6,8-pentamethylpyrromethene–BF2 complex 7n , RE 30. Diethyl 1,3,5,7-tetramethyl-8-cyanopyrromethene-2,6-dicarboxylate–BF2 complex, 7aa , and 1,3,5,7-tetramethyl-2,6-diethyl-8-cyanopyrromethene–BF2 complex, 7bb , offered examples of P–BF2 dyes with electron withdrawing substituents at the 8-position. The dye 7aa , λlas 617 nm, showed nearly twice the power efficiency that was obtained from rhodamine B, λlas 611 nm. 相似文献
243.
Chuanxiong Nie Dr. Badri Parshad Dr. Sumati Bhatia Prof. Dr. Chong Cheng Marlena Stadtmüller Dr. Alexander Oehrl Yannic Kerkhoff Dr. Thorsten Wolff Prof. Dr. Rainer Haag 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(36):15662-15666
In this study, we demonstrate the concept of “topology-matching design” for virus inhibitors. With the current knowledge of influenza A virus (IAV), we designed a nanoparticle-based inhibitor (nano-inhibitor) that has a matched nanotopology to IAV virions and shows heteromultivalent inhibitory effects on hemagglutinin and neuraminidase. The synthesized nano-inhibitor can neutralize the viral particle extracellularly and block its attachment and entry to the host cells. The virus replication was significantly reduced by 6 orders of magnitude in the presence of the reverse designed nano-inhibitors. Even when used 24 hours after the infection, more than 99.999 % inhibition is still achieved, which indicates such a nano-inhibitor might be a potent antiviral for the treatment of influenza infection. 相似文献
244.
Chuanxiong Nie Badri Parshad Sumati Bhatia Chong Cheng Marlena Stadtmüller Alexander Oehrl Yannic Kerkhoff Thorsten Wolff Rainer Haag 《Angewandte Chemie (International ed. in English)》2020,59(36):15532-15536
In this study, we demonstrate the concept of “topology‐matching design” for virus inhibitors. With the current knowledge of influenza A virus (IAV), we designed a nanoparticle‐based inhibitor (nano‐inhibitor) that has a matched nanotopology to IAV virions and shows heteromultivalent inhibitory effects on hemagglutinin and neuraminidase. The synthesized nano‐inhibitor can neutralize the viral particle extracellularly and block its attachment and entry to the host cells. The virus replication was significantly reduced by 6 orders of magnitude in the presence of the reverse designed nano‐inhibitors. Even when used 24 hours after the infection, more than 99.999 % inhibition is still achieved, which indicates such a nano‐inhibitor might be a potent antiviral for the treatment of influenza infection. 相似文献
245.
246.
Salah‐Eddine Stiriba Holger Frey Rainer Haag 《Angewandte Chemie (International ed. in English)》2002,41(8):1329-1334
Dendrimers are characterized by a combination of high end‐group functionality and a compact, precisely defined molecular structure. These characteristics can be used in biomedical applications, for example, for the amplification or multiplication of effects on a molecular level, or to create extremely high local concentrations of drugs, molecular labels, or probe moieties. A brief summary of the current state of the art in the field is given, and focuses on the application of dendrimers both in diagnostics as well as in therapy. In diagnostics, dendrimers that bear GdIII complexes are used as contrast agents in magnetic resonance imaging. DNA dendrimers have potential for routine use in high‐throughput functional genomic analysis, as well as for DNA biosensors. Dendrimers are also being investigated for therapeutics, for example, as carriers for controlled drug delivery, in gene transfection, as well as in boron neutron‐capture therapy. Furthermore, the antimicrobial activity of dendrimers has been studied. 相似文献
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249.
Cover Picture: Protein Interactions with Polymer Coatings and Biomaterials (Angew. Chem. Int. Ed. 31/2014)
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250.
Daniel Lauster Maria Glanz Markus Bardua Dr. Kai Ludwig Dr. Markus Hellmund Dr. Ute Hoffmann Prof. Dr. Alf Hamann Dr. Christoph Böttcher Prof. Dr. Rainer Haag Prof. Dr. Christian P. R. Hackenberger Prof. Dr. Andreas Herrmann 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(21):6025-6030