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Advanced photoresist technologies by intricate molecular brush architectures: Diblock brush terpolymer-based positive-tone photoresist materials 下载免费PDF全文
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Dendritic polycation (PG‐BEN) using polyglycerol as a core and secondary amine shell consisting of N1,N11‐bisethylnorspermine (BEN) was synthesized. Polymers containing primary amines in the shell (PG‐Nor and PG‐NH2) were synthesized as controls to allow evaluation of the shell effect on physicochemical and transfection properties of the polymers. All studied polymers condensed DNA and formed polyplexes with sizes less than 110 nm. PG‐BEN and PG‐Nor had a similar transfection activity that was fully comparable with that of the control polyethylenimine. Amongst the studied polymers, PG‐BEN demonstrated the lowest cytotoxicity, suggesting that PG‐BEN is a promising gene delivery vector with favorable transfection/toxicity profile. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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D‐Glucosamine in iron‐catalysed cross‐coupling reactions of Grignards with allylic and vinylic bromides: application to the synthesis of a key sitagliptin precursor 下载免费PDF全文
A sustainable D ‐glucosamine ligand is successfully introduced into iron‐catalysed C ? C cross‐coupling reactions for the first time. The Fe(acac)2/D ‐glucosamine·HCl/Et3N catalytic system was effective at 5 mol% loading in coupling reactions of Grignard reagents with organic bromides. Moderate to high efficiency was achieved with preserved stereochemistry when allyl (Csp3) or alkenyl (Csp2) bromides were coupled with phenylmagnesium (Csp2) or benzylmagnesium (Csp3) bromides. The catalytic system developed was also successfully applied for the novel and economic preparation of a Michael‐acceptor‐like starting material used in an alternative synthesis of the drug sitagliptin, a known blockbuster for the treatment of type II diabetes mellitus. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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Dr. Martina Čížková Prof. Lubomír Pospíšil Dr. Blanka Klepetářová Dr. Dušan Koval Dr. Filip Teplý 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(34):12154-12159
We report an innovative synthetic route to linear extended diquats (linquats). Our approach is short and efficient and features a highly modular reaction sequence based on two‐fold quaternization followed by the key intramolecular [2+2+2] alkyne cycloaddition. The physico‐chemical properties of four new linquats were characterized by spectroscopic methods, X‐ray crystallography, and electrochemistry complemented by information obtained from DFT calculations. Electron deficient N‐heteroaromatic cations with linear extended diquat motif with high electron affinities have been recently recognized as attractive n‐type semiconductors for chemical and biological sensing. Their advantageous redox properties such as very fast reversible electron transfers make the title compounds interesting for applications. 相似文献
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