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Yufen Zhao - One of the best experts on this subject based on the ideXlab platform.
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Progress in the Atherton-Todd Reaction and its stereochemical mechanism
SCIENTIA SINICA Chimica, 2015Co-Authors: Shuxia Cao, Yufen ZhaoAbstract:In this review, we summarize the literatures in the latest decades on the Atherton-Todd Reaction of the tetracoordinated and pentacoordinated phosphorus compounds containing P-H bond. Especially, the review focuses on the development of the stereochemical mechanism of the Atherton-Todd Reaction. Although the Reaction mechanism has been investigated for decades after the discovery of the Reaction, the earlier studies mainly concentrated on the Reaction intermediate. Up to the past dozen years, the stereochemical mechanism of the Atherton-Todd Reaction was studied in detail. However, up to now, there is few review and introduction to the stereochemical mechanism of the Atherton- Todd Reaction. We hope this article could compensate for this limitation, and it not only summarizes the general Atherton-Todd Reaction, but also introduces the recent research results on the stereochemical mechanism. It is considered that the further investigation on the stereochemical mechanism of the Atherton-Todd Reaction will be helpful to design and synthesize the novel tetracoordinated or pentacoordinated compounds with phosphorus chiral centers.
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synthesis and characterization of new pyrospirophosphoranes containing a p o p bond by the atherton Todd Reaction
Heteroatom Chemistry, 2015Co-Authors: Xiaohui You, Yufen Zhao, Jia Zheng, Wang Dai, Yanchun Guo, Shuxia CaoAbstract:The classical Atherton–Todd Reaction has been successfully applied to the synthesis of pentacoordinate pyrospirophosphoranes containing a P-O-P bond under mild conditions. The absolute configurations of the products were confirmed by X-ray diffraction analysis and spectroscopic identification. And 31P NMR chemical shifts of the products were correlated with stereochemistry. A possible mechanism for explaining the stereochemistry of the Reaction was proposed, and it could well explain the results of the Reactions of different pentacoordinate hydrospirophosphoranes.
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Synthesis and Characterization of New Pyrospirophosphoranes Containing a P‐O‐P Bond by the Atherton–Todd Reaction
Heteroatom Chemistry, 2014Co-Authors: Xiaohui You, Yufen Zhao, Jia Zheng, Wang Dai, Yanchun Guo, Shuxia CaoAbstract:The classical Atherton–Todd Reaction has been successfully applied to the synthesis of pentacoordinate pyrospirophosphoranes containing a P-O-P bond under mild conditions. The absolute configurations of the products were confirmed by X-ray diffraction analysis and spectroscopic identification. And 31P NMR chemical shifts of the products were correlated with stereochemistry. A possible mechanism for explaining the stereochemistry of the Reaction was proposed, and it could well explain the results of the Reactions of different pentacoordinate hydrospirophosphoranes.
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Highly Regioselective Synthesis of Novel 4-O-Phosphorylated Paeonol Analogs
Phosphorus Sulfur and Silicon and the Related Elements, 2012Co-Authors: Jie Wang, Fengling Yang, Yufen ZhaoAbstract:Abstract 4-O-phosphorylated paeonol derivatives were conveniently prepared by a facile method. Resacetophenone was prepared by the Friedel–Crafts acylation Reaction of acetic acid with resorcinol. It was then phosphorylated regioselectively at the 4-O position using the Atherton–Todd Reaction. An efficient, highly regioselective method to synthesize 4-O-phosphorylated paeonol derivatives is provided, and the approach has the merits of mild Reaction conditions. Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file.
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the synthesis of amino acid methyl ester 5 phosphoamidates of protected uridine
Phosphorus Sulfur and Silicon and The Related Elements, 2010Co-Authors: Yufen Zhao, W Z ChenAbstract:In this article, we used the Atherton–Todd Reaction to synthesize amino acid methyl ester 5′-phosphoamidates of uridine as prodrugs. Their structures were confirmed by 1H NMR, 31P NMR, 13C NMR, IR,...
Rong Zeng - One of the best experts on this subject based on the ideXlab platform.
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A zwitterionic serine modified chitosan derivative for improving protein stability and activity
International journal of biological macromolecules, 2020Co-Authors: Guanglin Zhang, Xingwen Huang, Wenrui Zhang, Rong ZengAbstract:Abstract A zwitterionic phosphoryldiserine (PDS)- chitosan conjugate was synthesized via Atherton-Todd Reaction, and its degree of substitution of PDS and structure were characterized by 1H and 31P NMR spectra, ICP, FTIR and XRD. Thermal analysis confirmed that there existed the freezing bound water surrounding PDS-chitosan due to the introduction of zwitterionic PDS groups onto chitosan backbone. In vitro cytotoxicity and hemolysis assay demonstrated that PDS-chitosan had excellent cell compatibility. UV adsorption and fluorescence spectra revealed that the model protein, bovine serum albumin (BSA) tended to keep its native conformation and showed better thermal stability in aqueous media in the presence of PDS-chitosan. We also found that the esterase-like activity of BSA could be enhanced by low concentration of PDS-chitosan (CBSA = 0.33 mg/mL, CPDS-chitosan = 0.0625 and 0.125 mg/mL, pH = 7.4, T = 25 °C). The results indicated that zwitterionic PDS-chitosan showed great potential for maintaining protein function in biomedical applications.
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Preparation, characterization and protein sorption of photo-crosslinked cell membrane-mimicking chitosan-based hydrogels
Carbohydrate polymers, 2016Co-Authors: Yunfei Zhao, Rong Zeng, Jianhao ZhaoAbstract:Photocrosslinkable biomimetic chitosan derivative, glycidyl methacrylate-phosphorylcholine-chitosan (PCCs-GMA) was synthesized through the combination of Atherton-Todd Reaction for coupling phosphorylcholine and ring opening Reaction of epoxides for attaching GMA, and confirmed by (1)H and (31)P NMR and Fourier transform infrared (FTIR) spectroscopy. The photo-crosslinking Reaction of PCCs-GMA with different degree of substitution (DS) of GMA allowed the formation of biomimetic hydrogels with tunable mechanical and swelling properties. Cold crystallization behaviors ascribed to their restrained freezing bound water were investigated using differential scanning calorimetry (DSC). The rheological and swelling behaviors, hemolysis as well as protein sorption of PCCs-GMA hydrogels were investigated in terms of the DS of GMA, using fibrinogen, bovine serum albumin and lysozyme as model proteins. Low irreversible protein sorption and non hemolytic results indicated that photo-crosslinked PCCs-GMA hydrogels may offer a promising candidate material with resistance to protein fouling in biomedical applications.
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Self-assemblied nanocomplexes based on biomimetic amphiphilic chitosan derivatives for protein delivery
Carbohydrate polymers, 2015Co-Authors: Hongwei Dong, Rong Zeng, Kai Guo, Jianhao ZhaoAbstract:Abstract A bio-inspired nanocarrier was developed for protein delivery based on biodegradable amphiphilic chitosan derivative (DCA–PCCs) with hydrophilic cell membrane mimic phosphorylcholine (PC) and hydrophobic deoxycholic acid (DCA) moieties, which was synthesized via the combination of Atherton–Todd Reaction and carbodiimide coupling Reaction. Using bovine serum albumin (BSA) as model protein, it was found that DCA–PCCs with suitable degree of substitution of PC and DCA moieties can load proteins by forming nanocomplexes via a solvent evaporation method. The physicochemical characteristics of BSA/DCA–PCCs nanocomplexes were investigated by Zetasizer, atomic force microscopy (AFM) and Fourier-transform infrared (FT-IR) spectroscopy. In vitro biological evaluation revealed BSA/DCA–PCCs nanocomplexes as blank DCA–PCCs nanoparticles had excellent cytocompatibility and hemocompatibility mainly due to the presence of cell membrane mimic phosphorylcholine. BSA release results suggested BSA/DCA–PCCs nanocomplexes showed a sustained release behavior following first order exponential decay kinetics. The results indicated DCA–PCCs provided a promising approach for effectively delivering therapeutic proteins.
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in vitro drug release and biological evaluation of biomimetic polymeric micelles self assembled from amphiphilic deoxycholic acid phosphorylcholine chitosan conjugate
Materials Science and Engineering: C, 2014Co-Authors: Minming Wu, Mei Tu, Rong Zeng, Hongwei Dong, Jianhao ZhaoAbstract:Abstract Novel biomimetic amphiphilic chitosan derivative, deoxycholic acid–phosphorylcholine–chitosan conjugate (DCA–PCCs) was synthesized based on the combination of Atherton–Todd Reaction for coupling phosphorylcholine (PC) and carbodiimide coupling Reaction for linking deoxycholic acid (DCA) to chitosan. The chemical structure of DCA–PCCs was characterized by 1 H and 31 P nuclear magnetic resonance (NMR). The self-assembly of DCA–PCCs in water was analyzed by fluorescence measurements, dynamic laser light-scattering (DLS), zeta potential and transmission electron microscopy (TEM) technologies. The results confirmed that the amphiphilic DCA–PCCs can self-assemble to form nanosized spherical micelles with biomimetic PC shell. In vitro biological evaluation revealed that DCA–PCCs micelles had low toxicity against NIH/3T3 mouse embryonic fibroblasts as well as good hemocompatibility. Using quercetin as a hydrophobic model drug, drug loading and release study suggested that biomimetic DCA–PCCs micelles could be used as a promising nanocarrier avoiding unfavorable biological response for hydrophobic drug delivery applications.
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A novel biomimetic chitosan-based nanocarrier with suppression of the protein-nanocarrier interactions
Materials Letters, 2012Co-Authors: Zehu Wang, Rong Zeng, Jianhao ZhaoAbstract:A novel approach to construct biomimetic nanocarriers with suppression of the protein-nanocarrier interactions was developed. Firstly, biomimetic N-phosphorylcholine-chitosan derivative (N-PCCs) with biomembrane-like phosphorylcholine (PC) group was successfully synthesized through Atherton-Todd Reaction and subsequently hydrolysis, and structurally characterized. Using bovine serum albumin (BSA) as a model protein, UV adsorption spectra and fluorescence spectra revealed that the interactions between N-PCCs and BSA were effectively suppressed and the conformation of BSA was almost unchanged with the addition of N-PCCs. Moreover, N-PCCs nanoparticles can be easily formed by ionic crosslinking with lower particle size and zeta potential value compared with Cs nanoparticles. The results suggested that biomimetic N-PCCs nanoparticles may be used as a promising nanocarrier avoiding unfavorable biological response for effectively delivering therapeutic and/or diagnostic agents.
Foad Kazemi - One of the best experts on this subject based on the ideXlab platform.
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trichloroisocyanuric acid as an efficient reagent for the synthesis of phosphoroamidates via atherton Todd Reaction under base free conditions
Synthesis, 2018Co-Authors: Babak Kaboudin, Atousa Donyavi, Foad KazemiAbstract:A simple, efficient, and novel method is developed for the synthesis of phosphoroamidates via an Atherton–Todd coupling Reaction of amines with dialkyl H-phosphite using trichloroisocyanuric acid as an efficient and safe reagent. Treatment of amines with dialkyl H-phosphite and trichloroisocyanuric acid under base-free conditions gives phosphoroamidates in moderate to good yields. The Reaction proceeded effectively to afford the corresponding phosphoroamidates via a dehydrogenative coupling of H-phosphonates with amines. This method is easy, rapid, and good-yielding for the synthesis of phosphoroamidates.
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Trichloroisocyanuric Acid as an Efficient Reagent for the Synthesis of Phosphoroamidates via Atherton–Todd Reaction under Base-Free Conditions
Synthesis, 2017Co-Authors: Babak Kaboudin, Atousa Donyavi, Foad KazemiAbstract:A simple, efficient, and novel method is developed for the synthesis of phosphoroamidates via an Atherton–Todd coupling Reaction of amines with dialkyl H-phosphite using trichloroisocyanuric acid as an efficient and safe reagent. Treatment of amines with dialkyl H-phosphite and trichloroisocyanuric acid under base-free conditions gives phosphoroamidates in moderate to good yields. The Reaction proceeded effectively to afford the corresponding phosphoroamidates via a dehydrogenative coupling of H-phosphonates with amines. This method is easy, rapid, and good-yielding for the synthesis of phosphoroamidates.
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Fe3O4@MgO Nanoparticles as an Efficient Recyclable Catalyst for the Synthesis of Phosphoroamidates via the Atherton—Todd Reaction.
ChemInform, 2016Co-Authors: Babak Kaboudin, Foad Kazemi, Fereshteh HabibiAbstract:A simple, and convenient method for the synthesis of phosphoroamidates via the Atherton—Todd coupling Reaction of amines with dialkyl phosphites is reported.
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fe3o4 mgo nanoparticles as an efficient recyclable catalyst for the synthesis of phosphoroamidates via the atherton Todd Reaction
ChemInform, 2016Co-Authors: Babak Kaboudin, Foad Kazemi, Fereshteh HabibiAbstract:A simple, and convenient method for the synthesis of phosphoroamidates via the Atherton—Todd coupling Reaction of amines with dialkyl phosphites is reported.
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fe3o4 mgo nanoparticles as an efficient recyclable catalyst for the synthesis of phosphoroamidates via the atherton Todd Reaction
Tetrahedron Letters, 2015Co-Authors: Babak Kaboudin, Foad Kazemi, Fereshteh HabibiAbstract:A simple and efficient method is presented for the synthesis of phosphoroamidates in moderate to good yield via the Atherton–Todd coupling of primary amines with H-dialkyl phosphites using Fe3O4@MgO nanoparticles as a recyclable catalyst.
Babak Kaboudin - One of the best experts on this subject based on the ideXlab platform.
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trichloroisocyanuric acid as an efficient reagent for the synthesis of phosphoroamidates via atherton Todd Reaction under base free conditions
Synthesis, 2018Co-Authors: Babak Kaboudin, Atousa Donyavi, Foad KazemiAbstract:A simple, efficient, and novel method is developed for the synthesis of phosphoroamidates via an Atherton–Todd coupling Reaction of amines with dialkyl H-phosphite using trichloroisocyanuric acid as an efficient and safe reagent. Treatment of amines with dialkyl H-phosphite and trichloroisocyanuric acid under base-free conditions gives phosphoroamidates in moderate to good yields. The Reaction proceeded effectively to afford the corresponding phosphoroamidates via a dehydrogenative coupling of H-phosphonates with amines. This method is easy, rapid, and good-yielding for the synthesis of phosphoroamidates.
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Trichloroisocyanuric Acid as an Efficient Reagent for the Synthesis of Phosphoroamidates via Atherton–Todd Reaction under Base-Free Conditions
Synthesis, 2017Co-Authors: Babak Kaboudin, Atousa Donyavi, Foad KazemiAbstract:A simple, efficient, and novel method is developed for the synthesis of phosphoroamidates via an Atherton–Todd coupling Reaction of amines with dialkyl H-phosphite using trichloroisocyanuric acid as an efficient and safe reagent. Treatment of amines with dialkyl H-phosphite and trichloroisocyanuric acid under base-free conditions gives phosphoroamidates in moderate to good yields. The Reaction proceeded effectively to afford the corresponding phosphoroamidates via a dehydrogenative coupling of H-phosphonates with amines. This method is easy, rapid, and good-yielding for the synthesis of phosphoroamidates.
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Fe3O4@MgO Nanoparticles as an Efficient Recyclable Catalyst for the Synthesis of Phosphoroamidates via the Atherton—Todd Reaction.
ChemInform, 2016Co-Authors: Babak Kaboudin, Foad Kazemi, Fereshteh HabibiAbstract:A simple, and convenient method for the synthesis of phosphoroamidates via the Atherton—Todd coupling Reaction of amines with dialkyl phosphites is reported.
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fe3o4 mgo nanoparticles as an efficient recyclable catalyst for the synthesis of phosphoroamidates via the atherton Todd Reaction
ChemInform, 2016Co-Authors: Babak Kaboudin, Foad Kazemi, Fereshteh HabibiAbstract:A simple, and convenient method for the synthesis of phosphoroamidates via the Atherton—Todd coupling Reaction of amines with dialkyl phosphites is reported.
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fe3o4 mgo nanoparticles as an efficient recyclable catalyst for the synthesis of phosphoroamidates via the atherton Todd Reaction
Tetrahedron Letters, 2015Co-Authors: Babak Kaboudin, Foad Kazemi, Fereshteh HabibiAbstract:A simple and efficient method is presented for the synthesis of phosphoroamidates in moderate to good yield via the Atherton–Todd coupling of primary amines with H-dialkyl phosphites using Fe3O4@MgO nanoparticles as a recyclable catalyst.
Zhao Yu-fen - One of the best experts on this subject based on the ideXlab platform.
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The Phosphorylation Reaction between Daidzein and Di-isopropyl Phosphite Studied by NMR and ESI-MS/MS
Chinese Journal of Magnetic Resonance, 2007Co-Authors: Zhao Yu-fenAbstract:The Atheron-Todd Reaction has been used extensively for synthesis of phosphates and phosphoroamidates. In this study, we showed that daidzein can be phosphorylated by a modified Atheron-Todd procedure in which dialkyl phosphite and tetrachloromethane mixture was dropped into a mixed solution of daidzein, trithylamine and DMF. The Reaction product was obtained with good yield, whose structure was determined by NMR, ESI-MS and X-ray crystallography.
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Synthesis and NMR Characterization of Diethyl Puerarin-7-yl Phosphate
Chinese Journal of Magnetic Resonance, 2005Co-Authors: Zhao Yu-fenAbstract:Puerarin,an isoflavone compound,is the bioactive component of traditional Chinese medicine puerarin lobate(wild).A novel diethyl puerarin-7-yl phosphate was synthesized by the Atherton-Todd Reaction with high productive yield.It was found that the compound synthesized has two sets of NMR signals at room temperature,suggesting the existence of two conformational isomers in solution.The1H chemical shifts of the compound were assigned using two-dimensional NMR techniques,including1H-detected heteronuclear multiple-quantum coherence and1H-detected multiple-bond heteronuclear multiple-quantum coherence.