117013-39-5Relevant academic research and scientific papers
Design of task-specific ionic liquids for catalytic conversion of CO 2 with aziridines under mild conditions
Zhao, Ya-Nan,Yang, Zhen-Zhen,Luo, Si-Hang,He, Liang-Nian
, p. 2 - 8 (2013)
A series of polyethylene glycol (PEG)-functionalized ionic liquids (ILs) were developed as recyclable and efficient catalysts for selective synthesis of 5-aryl-2-oxazolidinones from aziridines and CO2 without addition of any organic solvents or additives. In particular, high yields, chemo- and regio-selectivities of oxazolidinones were attained when BrDBNPEG 150DBNBr (DBN: 1,5-diazabicyclo[4.3.0]non-5-ene) was used as the catalyst, presumably due to activation of CO2 by the ether linkage in the PEG backbone, and stabilization of the ring-opened species of aziridine by the delocalized cation BrDBNPEG150DBN+. Furthermore, the catalyst could be reused for over four consecutive cycles without appreciable loss of catalytic activity and selectivity. The effects of catalyst structure and various reaction parameters on the catalytic performance were also investigated in detail. It was demonstrated that the catalyst worked well for a variety of aziridines producing the corresponding oxazolidinones in good yields and excellent regio-selectivities. Therefore, this solvent-free process could thus represent an environmentally friendly approach for ILs-catalyzed conversion of CO2 into value-added chemicals.
Synthesis of n-terminally linked protein dimers and trimers by a combined native chemical ligation-CuAAC click chemistry strategy
Xiao, Junpeng,Tolbert, Thomas J.
, p. 4144 - 4147 (2009)
A novel method for the synthesis of N-terminally linked protein multimers is reported. Azide and alkyne thioesters were synthesized for the N-terminal modification of expressed proteins using native chemical ligation (NCL). Proteins modified by these moie
Linear cationic click polymer for gene delivery: Synthesis, biocompatibility, and in Vitro Transfection
Gao, Yu,Chen, Lingli,Zhang, Zhiwen,Gu, Wangwen,Li, Yaping
, p. 3102 - 3111 (2010)
Sixteen novel cationic click polymers (CPs) were parallelly synthesized via the conjugation of four alkyne- functionalized monomers to four azide-functionalized monomers by "click chemistry". The biocompatibility of CPs was evaluated by in vitro cytotoxicity (MTT assay, Hoechst/PI apoptosis/necrosis assay, and cell cycle analysis) and blood compatibility tests (hemolysis and erythrocyte aggregation). The experimental results showed that the kind of amine groups, charge density, and number of methylene or ethylene glycol groups brought about the effect on toxicity of CPs. Among all polymers, two polymers (B1 and B2) showed good biocompatibility, inducing neither apoptosis nor necrosis at the test concentration and low hemolysis ratio and erythrocyte aggregation. In particular, B1 and B2 exhibited the comparable transfection efficiency compared with PEI (25 kDa) but much lower cytotoxicity. These results suggested that the novel cationic CPs could be promising carriers for gene delivery.
