A new metabonomics method was developed for simultaneous qualitative and quantitative analysis on esterified and nonesterified fatty acids (EFAs and NEFAs) in plasma. Merely 10 μL of plasma was required. The pretre...A new metabonomics method was developed for simultaneous qualitative and quantitative analysis on esterified and nonesterified fatty acids (EFAs and NEFAs) in plasma. Merely 10 μL of plasma was required. The pretreatment of the sample was simple without disposing the protein. After simple extraction and derivation, 15 FAs in plasma were precisely quantified. Gas chromatography tandem mass spectrometry (GC-MS) was used in the study and the quantities of the analytes, which varied in abundance over three orders of magnitude. The established method showed good accuracy. The curve correlation coefficients were all above 0.997. The RSDs of precision for all compounds were below 15% and recoveries were all between 80 and 110%. PLS-DA modal was used in the data management. 2009 Guo An Luo. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.展开更多
The 1-azido-2-chloro-4-nitrobenzene was prepared by nucleophilic substitution between 2-chloro-4-nitro-1-(trifluoromethylsulfinyl)benzene and sodium azide, and its structure was characterized by NMR spectrum and X-ray...The 1-azido-2-chloro-4-nitrobenzene was prepared by nucleophilic substitution between 2-chloro-4-nitro-1-(trifluoromethylsulfinyl)benzene and sodium azide, and its structure was characterized by NMR spectrum and X-ray single-crystal diffraction. It crystallizes in the monoclinic system, space group P21/n, Z = 8 and Mr = 198.57. A cultivation process of the single crystal of unstable aryl azide was provided. The group of trifluoromethyl sulfinyl was found for the first time to be a new excellent leaving group of aromatic nucleophilic substitution reactions.展开更多
A new compound N-naphthyl-2-deoxy-α-D-ribopyranosylamine was synthesized and structurally determined. It crystallizes in the orthorhombic system, space group P212121 with a = 8.361(2), b = 12.432(3), c = 12.791(...A new compound N-naphthyl-2-deoxy-α-D-ribopyranosylamine was synthesized and structurally determined. It crystallizes in the orthorhombic system, space group P212121 with a = 8.361(2), b = 12.432(3), c = 12.791(4) A^°, Z= 4, V= 1329.6(6) A^°^3, Dc= 1.295 g/cm^3, F(000) = 552, Cl5H17NO3 and Mr= 259.30. All the active hydrogen atoms are involved in the formation of hydrogen bonds in the molecule.展开更多
Recently, the Biginelli reaction, one of the most famous multicomponent reactions, has been introduced into the polymer chemistry to highly efficiently synthesize some interesting functional polymers. In this mini-rev...Recently, the Biginelli reaction, one of the most famous multicomponent reactions, has been introduced into the polymer chemistry to highly efficiently synthesize some interesting functional polymers. In this mini-review, several applications of the Biginelli reaction in polymer chemistry have been summarized, including polycondensation, post-polymerization modification,one-pot synthesis of well-defined polymer, etc. Meanwhile, the utilization of the Biginelli reaction in material science and chemical biology, and the future development of the Biginelli reaction in polymer chemistry have also been discussed.展开更多
A simple,fast,precise and eco-friendly analytical method for the determination of uric acid(UA) in human urine by ion chromatography(IC) was established.The sample pretreatment was not required,only needed centrif...A simple,fast,precise and eco-friendly analytical method for the determination of uric acid(UA) in human urine by ion chromatography(IC) was established.The sample pretreatment was not required,only needed centrifugation and filtration.The separation was carried out on a cation exchange column with 2.0 mmol/L nitric acid as mobile phase at the flow-rate 1.0 mL/min.A non-suppressed conductivity detector was used.The IC analysis time for one run was within 10 min under the optimized IC condition.The detection limits were 0.5μg/L(S/N = 3) for uric acid.The recovery was 100.1%while the relative standard deviation (RSD) was 1.8%from 10 measurements.展开更多
Five multinuclear cyclotriphosphazene ligands were synthesized and tested for their cleavage activities to plasmid DNA. All of these new compounds were confirmed by MS, ^1H NMR, ^31P NMR, ^13C NMR and IR. Preliminary ...Five multinuclear cyclotriphosphazene ligands were synthesized and tested for their cleavage activities to plasmid DNA. All of these new compounds were confirmed by MS, ^1H NMR, ^31P NMR, ^13C NMR and IR. Preliminary studies on the cleavage of pUC19 DNA in the presence of metal complexes were performed. The results revealed that these complexes could act as powerful catalysts under physiological conditions. The complexes 3b + Cu can effectively cleave DNA to nicked form, giving hydrolysis rate constant of 0.08/h under physiological conditions. An acid-base catalyzed DNA phosphate-diester hydrolysis mechanism was also orooosed.展开更多
Unnatural a-amino acids have been extensively used in the modern drug discovery and protein engineering studies. They have also found applications in the development of chiral molecular catalysts and the total synthes...Unnatural a-amino acids have been extensively used in the modern drug discovery and protein engineering studies. They have also found applications in the development of chiral molecular catalysts and the total synthesis of diverse natural products. Accordingly the development of cost-effective approaches for the preparation of unnatural a-amino acids has received increasing attentions. Among all the available methods for this purpose, direct C–H functionalization of simple amino acids represents one of the most attractive approaches because it exhibits good atom-economy and step-efficiency. In particular, selective functionalization of either the primary or secondary C(sp^3)–H bonds in the amino acids has been explored to make versatile C–C, C–N, C–O, C–B and C–F bonds to modify the side chain of amino acids and even peptides. The present review surveys the recent advances of synthesis of chiral unnatural a-amino acids and peptides through palladium-catalyzed functionalization of un-activated C(sp^3)–H bonds.展开更多
A cyano-substituted diarylethlene derivative aggregation-induced emission (ALE) dye with two amino end-groups and 4,4'-(hexafluoroisopropylidene)diphthalic anhydride were facilely incorporated into red fluorescen...A cyano-substituted diarylethlene derivative aggregation-induced emission (ALE) dye with two amino end-groups and 4,4'-(hexafluoroisopropylidene)diphthalic anhydride were facilely incorporated into red fluorescent organic nanoparticles (FONs) via room temperature anhydride ring-opening polymerization under an air atmosphere. These obtained RO-HFDA FONs were characterized by a series of techniques including gel permeation chromatography, Fourier transform infrared spectroscopy, size distribution and zeta potential measurements, UV-Vis absorption spectrum, fluorescent spectroscopy and transmission electron microscopy. Biocompatibility evaluation and cell uptake behavior of RO-HFDA FONs were further investigated to explore their potential biomedical application. We demonstrated that such FONs showed high water dispersibility, stable uniform spherical morphology (150-200 nm), broad excitation band (350-605 nm), intense red fluorescence (627 nm) and excellent biocompatibility, making them promising for cell imaging applications.展开更多
We herein report the synthesis and metal-directed coordination self-assembly behaviors of three new macrocyc- lic azacalix[4]aromatics that comprise various numbers of pyridine and pyrazine rings bridged by N-CH3 grou...We herein report the synthesis and metal-directed coordination self-assembly behaviors of three new macrocyc- lic azacalix[4]aromatics that comprise various numbers of pyridine and pyrazine rings bridged by N-CH3 groups. Structural characterization of 1--3 explored that their conformations are fluxional in solution and each adopts a 1,3-alternate configuration in crystalline solids. The macrocyclic skeletons in azacalixaromatic 1--3 afford a good platform to designedly arrange coordination sites in a unique way relative to conventional multidentate ligands. Solid-state structures of three coordination self-assembled silver complexes (13--15) of 1 --3 determined by X-ray crystallography suggest that the nitrogen atoms on procumbent aromatics have better coordination ability than those on perpendicular aromatics and dictate the whole coordination self-assemblies. Unique discrete and 1D chain-like structures were thus obtained. This system may afford a deeper insight into the coordination self-assembly studies of heteroatom-bridged calixaromatics, possibly extending potential application of this novel macrocyclic polyden- tate organic compounds in the synthesis of functional metal organic framework formation.展开更多
A novel fan-shaped C3 molecule with three glycyrrhetinic acid units was synthesized via "click chemistry" in high yield and the self-assembly characteristics were studied in different mixed solvents.
The coupling reactions of simple methyl ketones with o-bromoacetophenones and subsquential cyclization reactions were realized to produce a range of 1-naphthols. These cascade reactions were initiated by a rare Cu-cat...The coupling reactions of simple methyl ketones with o-bromoacetophenones and subsquential cyclization reactions were realized to produce a range of 1-naphthols. These cascade reactions were initiated by a rare Cu-catalyzed arylation reaction of methyl ketones with aromatic bromides.展开更多
A new fluorescent "on-off' chemosensor for Hg2+ initiated by a derivative of rhodamine B was designed and synthesized. Compound 1 exhibited high sensitivity and selectivity for Hg2+ over other commonly coexistent ...A new fluorescent "on-off' chemosensor for Hg2+ initiated by a derivative of rhodamine B was designed and synthesized. Compound 1 exhibited high sensitivity and selectivity for Hg2+ over other commonly coexistent metal ions in aqueous media, Upon the addition of Hg2+, the spirocyclic ring of probe is opened and a significant enhancement of visible color and fluorescence in the range of 500-600 nm is observed, The colorimetric and fluorescent response to Hg2+ can be conveniently detected by the naked eye, which provides a facile method for visual detection of Hg2+, From the molecular structure and spectral results of 1, an irreversible, hydrolysis, desulfurization reaction mechanism is proposed.展开更多
By using an easily available PEG derivative and biopolymer chitosan, a self-healing hydrogel has been facilely prepared through the dynamic Schiff base. This biocompatible self-healing hydrogel can be used for drug-de...By using an easily available PEG derivative and biopolymer chitosan, a self-healing hydrogel has been facilely prepared through the dynamic Schiff base. This biocompatible self-healing hydrogel can be used for drug-delivery, 3D cell culture and as a basic platform to develop some organic-inorganic biohybrids. This mini-review summarized recent research about that chitosan based self-healing hydrogel and related materials, and discussed some future bio-applications of that hydrogel展开更多
基金offered by China-Japan Friendship Hospital(Beijing,China)supported by grantfrom the National Basic Research Development Program of China(973 Program,No.2005CB523503)the National Natural Science Foundations of China(Nos.90709045 and 20805026)
文摘A new metabonomics method was developed for simultaneous qualitative and quantitative analysis on esterified and nonesterified fatty acids (EFAs and NEFAs) in plasma. Merely 10 μL of plasma was required. The pretreatment of the sample was simple without disposing the protein. After simple extraction and derivation, 15 FAs in plasma were precisely quantified. Gas chromatography tandem mass spectrometry (GC-MS) was used in the study and the quantities of the analytes, which varied in abundance over three orders of magnitude. The established method showed good accuracy. The curve correlation coefficients were all above 0.997. The RSDs of precision for all compounds were below 15% and recoveries were all between 80 and 110%. PLS-DA modal was used in the data management. 2009 Guo An Luo. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.
文摘The 1-azido-2-chloro-4-nitrobenzene was prepared by nucleophilic substitution between 2-chloro-4-nitro-1-(trifluoromethylsulfinyl)benzene and sodium azide, and its structure was characterized by NMR spectrum and X-ray single-crystal diffraction. It crystallizes in the monoclinic system, space group P21/n, Z = 8 and Mr = 198.57. A cultivation process of the single crystal of unstable aryl azide was provided. The group of trifluoromethyl sulfinyl was found for the first time to be a new excellent leaving group of aromatic nucleophilic substitution reactions.
基金supported by the National Natural Science Foundation of China (No. 20132020)
文摘A new compound N-naphthyl-2-deoxy-α-D-ribopyranosylamine was synthesized and structurally determined. It crystallizes in the orthorhombic system, space group P212121 with a = 8.361(2), b = 12.432(3), c = 12.791(4) A^°, Z= 4, V= 1329.6(6) A^°^3, Dc= 1.295 g/cm^3, F(000) = 552, Cl5H17NO3 and Mr= 259.30. All the active hydrogen atoms are involved in the formation of hydrogen bonds in the molecule.
基金supported by the National Natural Science Foundation of China(21574073,21372033)
文摘Recently, the Biginelli reaction, one of the most famous multicomponent reactions, has been introduced into the polymer chemistry to highly efficiently synthesize some interesting functional polymers. In this mini-review, several applications of the Biginelli reaction in polymer chemistry have been summarized, including polycondensation, post-polymerization modification,one-pot synthesis of well-defined polymer, etc. Meanwhile, the utilization of the Biginelli reaction in material science and chemical biology, and the future development of the Biginelli reaction in polymer chemistry have also been discussed.
文摘A simple,fast,precise and eco-friendly analytical method for the determination of uric acid(UA) in human urine by ion chromatography(IC) was established.The sample pretreatment was not required,only needed centrifugation and filtration.The separation was carried out on a cation exchange column with 2.0 mmol/L nitric acid as mobile phase at the flow-rate 1.0 mL/min.A non-suppressed conductivity detector was used.The IC analysis time for one run was within 10 min under the optimized IC condition.The detection limits were 0.5μg/L(S/N = 3) for uric acid.The recovery was 100.1%while the relative standard deviation (RSD) was 1.8%from 10 measurements.
基金supports from the NNSFC(Nos.20602032,20732004 and 20572061).
文摘Five multinuclear cyclotriphosphazene ligands were synthesized and tested for their cleavage activities to plasmid DNA. All of these new compounds were confirmed by MS, ^1H NMR, ^31P NMR, ^13C NMR and IR. Preliminary studies on the cleavage of pUC19 DNA in the presence of metal complexes were performed. The results revealed that these complexes could act as powerful catalysts under physiological conditions. The complexes 3b + Cu can effectively cleave DNA to nicked form, giving hydrolysis rate constant of 0.08/h under physiological conditions. An acid-base catalyzed DNA phosphate-diester hydrolysis mechanism was also orooosed.
文摘Unnatural a-amino acids have been extensively used in the modern drug discovery and protein engineering studies. They have also found applications in the development of chiral molecular catalysts and the total synthesis of diverse natural products. Accordingly the development of cost-effective approaches for the preparation of unnatural a-amino acids has received increasing attentions. Among all the available methods for this purpose, direct C–H functionalization of simple amino acids represents one of the most attractive approaches because it exhibits good atom-economy and step-efficiency. In particular, selective functionalization of either the primary or secondary C(sp^3)–H bonds in the amino acids has been explored to make versatile C–C, C–N, C–O, C–B and C–F bonds to modify the side chain of amino acids and even peptides. The present review surveys the recent advances of synthesis of chiral unnatural a-amino acids and peptides through palladium-catalyzed functionalization of un-activated C(sp^3)–H bonds.
基金financially supported by the National Natural Science Foundation of China(Nos.21134004,21201108 and 51363016)the National 973 Project(No.2011CB935700)China Postdoctoral Science Foundation(Nos.2012M520243,2013T60100)
文摘A cyano-substituted diarylethlene derivative aggregation-induced emission (ALE) dye with two amino end-groups and 4,4'-(hexafluoroisopropylidene)diphthalic anhydride were facilely incorporated into red fluorescent organic nanoparticles (FONs) via room temperature anhydride ring-opening polymerization under an air atmosphere. These obtained RO-HFDA FONs were characterized by a series of techniques including gel permeation chromatography, Fourier transform infrared spectroscopy, size distribution and zeta potential measurements, UV-Vis absorption spectrum, fluorescent spectroscopy and transmission electron microscopy. Biocompatibility evaluation and cell uptake behavior of RO-HFDA FONs were further investigated to explore their potential biomedical application. We demonstrated that such FONs showed high water dispersibility, stable uniform spherical morphology (150-200 nm), broad excitation band (350-605 nm), intense red fluorescence (627 nm) and excellent biocompatibility, making them promising for cell imaging applications.
基金Financial support by the National Natural Science Foundation of China,the National Basic Research Program of China (973 program,2011CB932501 and 2013CB834501) is gratefully acknowledged.This work is also supported by Tsinghua University Initiative Scientific Research Program
文摘We herein report the synthesis and metal-directed coordination self-assembly behaviors of three new macrocyc- lic azacalix[4]aromatics that comprise various numbers of pyridine and pyrazine rings bridged by N-CH3 groups. Structural characterization of 1--3 explored that their conformations are fluxional in solution and each adopts a 1,3-alternate configuration in crystalline solids. The macrocyclic skeletons in azacalixaromatic 1--3 afford a good platform to designedly arrange coordination sites in a unique way relative to conventional multidentate ligands. Solid-state structures of three coordination self-assembled silver complexes (13--15) of 1 --3 determined by X-ray crystallography suggest that the nitrogen atoms on procumbent aromatics have better coordination ability than those on perpendicular aromatics and dictate the whole coordination self-assemblies. Unique discrete and 1D chain-like structures were thus obtained. This system may afford a deeper insight into the coordination self-assembly studies of heteroatom-bridged calixaromatics, possibly extending potential application of this novel macrocyclic polyden- tate organic compounds in the synthesis of functional metal organic framework formation.
基金Project supported by the National Natural Science Foundation of China (Nos. 20772071, 20972086) and the Specialized Research Fund for the Doctoral Program of Higher Education (No. 20090002110060).
文摘A novel fan-shaped C3 molecule with three glycyrrhetinic acid units was synthesized via "click chemistry" in high yield and the self-assembly characteristics were studied in different mixed solvents.
基金supported by National Natural Science Foundation of China (Nos. 21102080, 21372138)Tsinghua University Initiative Scientific Research Program (No. 2011Z02150)
文摘The coupling reactions of simple methyl ketones with o-bromoacetophenones and subsquential cyclization reactions were realized to produce a range of 1-naphthols. These cascade reactions were initiated by a rare Cu-catalyzed arylation reaction of methyl ketones with aromatic bromides.
基金financially supported by the National Natural Science Foundation of China(Nos.20972143,21375113)Program for New Century Excellent Talents in University(No.NCET-11-0950)
文摘A new fluorescent "on-off' chemosensor for Hg2+ initiated by a derivative of rhodamine B was designed and synthesized. Compound 1 exhibited high sensitivity and selectivity for Hg2+ over other commonly coexistent metal ions in aqueous media, Upon the addition of Hg2+, the spirocyclic ring of probe is opened and a significant enhancement of visible color and fluorescence in the range of 500-600 nm is observed, The colorimetric and fluorescent response to Hg2+ can be conveniently detected by the naked eye, which provides a facile method for visual detection of Hg2+, From the molecular structure and spectral results of 1, an irreversible, hydrolysis, desulfurization reaction mechanism is proposed.
基金supported by the National Natural Science Foundation of China (No. 21534006)
文摘By using an easily available PEG derivative and biopolymer chitosan, a self-healing hydrogel has been facilely prepared through the dynamic Schiff base. This biocompatible self-healing hydrogel can be used for drug-delivery, 3D cell culture and as a basic platform to develop some organic-inorganic biohybrids. This mini-review summarized recent research about that chitosan based self-healing hydrogel and related materials, and discussed some future bio-applications of that hydrogel