Novel hydrophilic NaYF4:Yb^3+,Tm^3+@NaGdF4:Ce^3+,Eu^3+double-jacket microtubes(DJMTs)with upconversion/downconversion dual-mode luminescence were designed and prepared through epitaxial growth of NaGdF4:Ce^3+,Eu^3+she...Novel hydrophilic NaYF4:Yb^3+,Tm^3+@NaGdF4:Ce^3+,Eu^3+double-jacket microtubes(DJMTs)with upconversion/downconversion dual-mode luminescence were designed and prepared through epitaxial growth of NaGdF4:Ce^3+,Eu^3+shell onto the NaYF4:Yb^3+,Tm^3+microtube via poly(acrylic acid)(PAA)mediated hydrothermal method.It is demonstrated that PAA ligand played an important role in guiding the direct growth of NaGdF4:Ce^3+,Eu^3+shell onto the surface of NaYF4:Yb^3+,Tm^3+parent microtubes.The growth of NaGdF4:Ce^3+,Eu^3+shell experienced a crystal phase transition fromβ-NaGdF4 andβ-NaYF4 mixture toβ-NaYF4@NaGdF4 composite crystal,and morphology evolution from mixture ofβ-NaGdF4:Ce^3+,Eu^3+nanorods andβ-NaYF4:Yb^3+,Tm^3+microtubes to NaYF4:Yb^3+,Tm^3+@NaGdF4:Ce^3+,Eu^3+DJMTs.The formation mechanism of DJMTs was the dissolution−renucleation ofβ-NaGdF4:Ce^3+,Eu^3+nanorods and the growth ofβ-NaGdF4:Ce^3+,Eu^3+shell via the classical Ostwald ripening mechanism.The as-prepared DJMTs could exhibit blue upconversion and red downconversion luminescence,which was further made into environmentally benign luminescent inks for creating highly secured and fluorescent-based anti-counterfeiting patterns via inkjet printing.展开更多
The title complex [Cu2(bipy)2OAcClOH]TsTausH3H2O(C31H37Cl- Cu2N5O11S2) has been synthesized by the reaction of 2,2?bipyridine(bipy), N-P-tolysulfony taurine (TsTausH) and copper acetate in water-ethanol solution, and ...The title complex [Cu2(bipy)2OAcClOH]TsTausH3H2O(C31H37Cl- Cu2N5O11S2) has been synthesized by the reaction of 2,2?bipyridine(bipy), N-P-tolysulfony taurine (TsTausH) and copper acetate in water-ethanol solution, and its crystal structure was determined by X-ray diffraction method. The crystal belongs to triclinic, space group P with a = 0.74485(14), b = 1.6094(3), c = 1.7472(3) nm, a = 114.662(4), b = 99.997(4), g = 93.218(4), V = 1.8551(6) nm3, Mr = 882.31, Z = 2, Dc = 1.580 g/cm3, m = 1.395 mm-1 and F(000) = 906. The complex is a binuclear copper compound, and the two copper ions nearly have the same coordination environment. There exists MM bond in the complex. The distance of Cu(1)Cu(2) is 0.29747(7) nm. The two ions form two distorted octahedral geometries.展开更多
By the reactions of [Rh2Co2(CO)12] 1 with functionally substituted alkyne ligands HC≡CR 2 (R = FeCp2) and 3 (R = 2-OH-C6H4COOCH2), respectively in n-hexane at room temperature, two new cluster derivatives [Rh2Co2(CO)...By the reactions of [Rh2Co2(CO)12] 1 with functionally substituted alkyne ligands HC≡CR 2 (R = FeCp2) and 3 (R = 2-OH-C6H4COOCH2), respectively in n-hexane at room temperature, two new cluster derivatives [Rh2Co2(CO)6(-CO)4(4, 2-HC≡CR)] 4 (R = FeCp2) and 5 (R = 2-OH-C6H4COOCH2) were obtained respectively. The alkyne was inserted into the CoCo bond of cluster 1 to give two butterfly clusters. Cluster 4 has been determined by single-crystal X-ray diffraction. Crystallographic data: C22H10Co2FeO10Rh2, Mr = 813.83, orthorhombic, space group P212121, a = 11.5318(7), b = 12.6572(7), c = 17.018(1) ? V = 2483.9(3) 3, Z = 4, Dc = 2.176 g/cm3, F(000) = 1568, = 3.233 mm-1, the final R = 0.0366 and wR = 0.0899 for 5367 observed reflections with I > 2(I). The two clusters have also been characterized by elemental analysis, IR and 1H-NMR spectroscopy.展开更多
A novel complex [Cd2(phen)4(fca)2](ClO4)2(H2O)2 (fca = dianion of 3-ferrocenyl- 2-crotonic acid, phen = 1,10-phenanthroline) has been synthesized and characterized by X-ray single-crystal structure analysis. It crysta...A novel complex [Cd2(phen)4(fca)2](ClO4)2(H2O)2 (fca = dianion of 3-ferrocenyl- 2-crotonic acid, phen = 1,10-phenanthroline) has been synthesized and characterized by X-ray single-crystal structure analysis. It crystallizes in triclinic system, space group P?with a = 11.6297(5), b = 12.5165(5), c = 13.8986(6) ? a = 63.345(1), b = 87.747(1), g = 71.862(1), V = 1706.20(1) ?, Z = 1, Dc = 1.673 g/cm3, F(000) = 868 and m(MoKa) = 1.185 mm-1 (l = 0.71073 ). R = 0.0800 and wR = 0.1793 for 7653 observed reflections (I > 2s(I)). The structure consists of a dinuclear cation [Cd2(phen)4(fca)2]2+, two discrete perchlorate anions and two water molecules. The cationic part of the complex shows a tetrametallic core in which two fca groups act as the (O, O) bridging ligands between two cadmium(Ⅱ) ions with a distorted octahedral environment. The Cd…Cd intradimer distance is 4.128 ?展开更多
The reduction of an aqueous solution of sodium molybdate by iron powder at low pH value (～0.83), in the presence of ethylenediaminetetraacetate (EDTA) ligand, gives the title compound [Fe(H 2O) 6][Mo 2O 4(EDTA)]·...The reduction of an aqueous solution of sodium molybdate by iron powder at low pH value (～0.83), in the presence of ethylenediaminetetraacetate (EDTA) ligand, gives the title compound [Fe(H 2O) 6][Mo 2O 4(EDTA)]·5H 2O 1, which was characterized by elemental analysis, IR and X ray single crystal diffraction techniques. Compound 1 crystallizes in monoclinic system, space group P2 1/c, C 10 H 34 N 2FeMo 2O 23 , M r=798.12, a=8.781(1), b=14.081(1), c=21.353(1) , β= 92\^688(1)°, V = 2637.2(3) 3, Z = 4, D c = 2.010 g·cm -3 , μ = 1.579 mm -1 , F (000)=1608, the final R =0.0530 and wR =0.1271 for 3312 observed reflections. The binuclear oxomolybdenum(V) anion and the six coordinated Fe(II) cation are linked to infinite three dimensional network through several hydrogen bonds towards different directions between crystal waters, Fe(II) cation and Mo(V) anion.展开更多
A new cyano-bridged Gadolinium^(Ⅲ)-Iron^(Ⅲ)complex{[Gd(DMF)_(3)(DMSO)(H_(2)O)_(3)]2H_(2)0(DMF=N,N·-dimethylformamide;DMSO=dimethylsulfoxidel}was synthesized by the grinding reaction method,.It crysta-]llizes in...A new cyano-bridged Gadolinium^(Ⅲ)-Iron^(Ⅲ)complex{[Gd(DMF)_(3)(DMSO)(H_(2)O)_(3)]2H_(2)0(DMF=N,N·-dimethylformamide;DMSO=dimethylsulfoxidel}was synthesized by the grinding reaction method,.It crysta-]llizes in the triclinic.,space group P1 with ceIl parameters:a=O.90363(2)nm,b=1.25078(3)nm,c=1.41303(1)nm,穋m^(-3),Z=2,Mr=756.72,F(000)=760,Ⅲ)and the approxi-mately oriented octahedrally sixfold-coordinated Fe(Ⅲ)are linked by a cyano-bridge group to construct a dinuclear compound.The{[Gd(DMF)_(3)(DMSO)(H_(2)O)_(3)](Ⅲ)-Fe(Ⅲ)interaction is antiferromagnetic.CCDC:223430.展开更多
Four cyanide-bridged heterometallic complexes { [CuPb（L1）][FenI（bpb）（CN）2] }2-（C104）2.2H20.2CH3CN （1）, { [CuPb（LI）]2[FeII （CN）6]（HzO）z}＇10H20 （2）, {[Cu2（L2）][Fent（bpb）（CN）2]2}＇2H20＇2CH3OH （...Four cyanide-bridged heterometallic complexes { [CuPb（L1）][FenI（bpb）（CN）2] }2-（C104）2.2H20.2CH3CN （1）, { [CuPb（LI）]2[FeII （CN）6]（HzO）z}＇10H20 （2）, {[Cu2（L2）][Fent（bpb）（CN）2]2}＇2H20＇2CH3OH （3） and {[Cu2（L2）]3[FeIII（CN）6]z（H20）2}-10H20 （4） have been synthesized by treating K[Fem（bpb）（CN）2] [bpb2-=l,2-bis（pyridine-2-carboxamido）benzenate] and K3[Feln（CN）]6 with dinuc[ear compartmental macrocyclic Schiff-base complexes [CuPh（LI）].（C104）2 or [Cu2（L2）]-（CIO4）2, in which H2LJ was derived from 2,6-diformyl-4-methyl-phenol, ethylenediamine, and diethylenetriamine in the molar ratio of 2：1：1 and H2L2 from 2,6-diformyl-4-methyl-phenol and propylenediamine in the molar ratio of 1：1. Single crystal X-ray diffraction analysis reveals that compound 1 displays a cyclic hexanuclear heterotrimetallic molecular structure with alternating [Fem（bpb）（CN）2]- and [CuPb（L＋）]2＋ units. Complex 2 is of a neutral dumb-bell-type pentanuclear molecular configuration consisting of one [Fe（CN）6]4- anion sandwiched in two [CuPu（L1）]2＋ cations, and the pentanuclear moieties are further connected by the hydro- gen bonding to give a 2D supramolecular framework. Heterobimetallic complex 3 is a tetranuclear molecule composed of a centrosymmetric [Cuz（L2）]2＋ segment and two terminal cyanide-containing blocks [Fetn（bpb）（CN）2]-. Octanuclear compound 4 is built from two [Fe（CN）6]3- anions sandwiched in the three [Cu2L2]2＋ cations. Investigation of their magnetic properties reveals the overall antiferromagnetic behavior in the series of complexes except 2.展开更多
As an im portant branch of fiber-shaped energy storage devices, the fiber-shaped supercapacitor has been widely studied recently. However, it remains challenging to simultaneously achieve fast electron transport and e...As an im portant branch of fiber-shaped energy storage devices, the fiber-shaped supercapacitor has been widely studied recently. However, it remains challenging to simultaneously achieve fast electron transport and excellent ion accessibility in one single fiber electrode of the fibershaped supercapacitor. Herein, a novel family of amphiphilic core-sheath structured carbon nanotube composite fibers has been developed and applied to the fiber-shaped supercapacitor to address the above challenge. The polyaniline-modified hydrophilic sheath of the composite fiber electrode effectively enhanced the electrochemical property via advancing ion accessibility, while Au-deposited hydrophobic core demonstrated improved electrical conductivity by fast electron supply. On the basis of a synergistic effect, a remarkable specific capacitance of 324 F cm^-3 at 0.5 A cm^-3 and greatly enhanced rate performance were achieved, i.e” a 79% retention (256 F cm 3) at 50 A cm^-3. The obtained fiber-shaped supercapacitor finally displayed remarkable energy and power densities of 7.2 mW h cm 3 and 10 W cm^-3, respectively. The strategy developed herein also presents a general pathway towards novel fiber electrodes for high-performance wearable devices.展开更多
Three new isostructural binuclear transition metal complexes with azido ion and 1,2-bis（3-（pyridin-2-yl）-lH-pyrazol-1- yl）ethane （bppe）, formulated as [M2（N3）2（bppe）2]（C104）2 （M = Co, 1; Ni, 2; Cu, 3）, w...Three new isostructural binuclear transition metal complexes with azido ion and 1,2-bis（3-（pyridin-2-yl）-lH-pyrazol-1- yl）ethane （bppe）, formulated as [M2（N3）2（bppe）2]（C104）2 （M = Co, 1; Ni, 2; Cu, 3）, were successfully synthesized. They were structurally and magnetically characterized. In 1-3, the double azido ions link two adjacent octahedral metal centers together in the end-to-on mode （EO）, with the M-NEo-M angles of 99.41°, 100.24° and 99.80°, respectively. The co-ligand bppe acts as terminal ligand to saturate the remaining coordination sites. The magnetic properties of 1-3 have been investigated in the tem- perature range of 2-300 K. Fitting of the magnetic susceptibility data revealed the occurrence of the strong ferromagnetic in- teractions [J = 26.32 cm-1 （1）, J = 38.23 cm-1 （2） and J = 139.83 cm-1 （3）]. Density functional theory calculations have been performed on 1-3 to provide a magneto-structural correlation of the ferromagnetic behavior.展开更多
G-quadruplexes comprise a class of secondary structures that are formed in guanine-rich sequences in eukaryotic genomes and play a crucial role in the regulation of many biological events.G-quadruplexes have become ta...G-quadruplexes comprise a class of secondary structures that are formed in guanine-rich sequences in eukaryotic genomes and play a crucial role in the regulation of many biological events.G-quadruplexes have become targets for anticancer drugs with high selectivity vs.duplex DNA and low cytotoxicity against normal cells.Natural products and their derivatives display polymorphism,structural complexity,and potent activity.It is,therefore,reasonable to seek ligands targeting G-quadruplexes from natural products.Recently,many successful examples have been reported,showing ligands with excellent anticancer activities.In this review,we summarized the development of research on natural products and derivatives that target G-quadruplex structures in an effort to guide future studies.展开更多
基金Project(51874129)supported by the National Natural Science Foundation of ChinaProjects(2018JJ3115,2019JJ60049)supported by the Science Foundation of Hunan Province,ChinaProjects(19B153,19B158)supported by the Scientific Research Fund of Hunan Provincial Education Department,China。
文摘Novel hydrophilic NaYF4:Yb^3+,Tm^3+@NaGdF4:Ce^3+,Eu^3+double-jacket microtubes(DJMTs)with upconversion/downconversion dual-mode luminescence were designed and prepared through epitaxial growth of NaGdF4:Ce^3+,Eu^3+shell onto the NaYF4:Yb^3+,Tm^3+microtube via poly(acrylic acid)(PAA)mediated hydrothermal method.It is demonstrated that PAA ligand played an important role in guiding the direct growth of NaGdF4:Ce^3+,Eu^3+shell onto the surface of NaYF4:Yb^3+,Tm^3+parent microtubes.The growth of NaGdF4:Ce^3+,Eu^3+shell experienced a crystal phase transition fromβ-NaGdF4 andβ-NaYF4 mixture toβ-NaYF4@NaGdF4 composite crystal,and morphology evolution from mixture ofβ-NaGdF4:Ce^3+,Eu^3+nanorods andβ-NaYF4:Yb^3+,Tm^3+microtubes to NaYF4:Yb^3+,Tm^3+@NaGdF4:Ce^3+,Eu^3+DJMTs.The formation mechanism of DJMTs was the dissolution−renucleation ofβ-NaGdF4:Ce^3+,Eu^3+nanorods and the growth ofβ-NaGdF4:Ce^3+,Eu^3+shell via the classical Ostwald ripening mechanism.The as-prepared DJMTs could exhibit blue upconversion and red downconversion luminescence,which was further made into environmentally benign luminescent inks for creating highly secured and fluorescent-based anti-counterfeiting patterns via inkjet printing.
基金This work was supported by the NSF of Guangxi Province (0339034) and the Science Research Foundation of Guangxi Universities
文摘The title complex [Cu2(bipy)2OAcClOH]TsTausH3H2O(C31H37Cl- Cu2N5O11S2) has been synthesized by the reaction of 2,2?bipyridine(bipy), N-P-tolysulfony taurine (TsTausH) and copper acetate in water-ethanol solution, and its crystal structure was determined by X-ray diffraction method. The crystal belongs to triclinic, space group P with a = 0.74485(14), b = 1.6094(3), c = 1.7472(3) nm, a = 114.662(4), b = 99.997(4), g = 93.218(4), V = 1.8551(6) nm3, Mr = 882.31, Z = 2, Dc = 1.580 g/cm3, m = 1.395 mm-1 and F(000) = 906. The complex is a binuclear copper compound, and the two copper ions nearly have the same coordination environment. There exists MM bond in the complex. The distance of Cu(1)Cu(2) is 0.29747(7) nm. The two ions form two distorted octahedral geometries.
基金the National Natural Science Foundation of China (29871061)
文摘By the reactions of [Rh2Co2(CO)12] 1 with functionally substituted alkyne ligands HC≡CR 2 (R = FeCp2) and 3 (R = 2-OH-C6H4COOCH2), respectively in n-hexane at room temperature, two new cluster derivatives [Rh2Co2(CO)6(-CO)4(4, 2-HC≡CR)] 4 (R = FeCp2) and 5 (R = 2-OH-C6H4COOCH2) were obtained respectively. The alkyne was inserted into the CoCo bond of cluster 1 to give two butterfly clusters. Cluster 4 has been determined by single-crystal X-ray diffraction. Crystallographic data: C22H10Co2FeO10Rh2, Mr = 813.83, orthorhombic, space group P212121, a = 11.5318(7), b = 12.6572(7), c = 17.018(1) ? V = 2483.9(3) 3, Z = 4, Dc = 2.176 g/cm3, F(000) = 1568, = 3.233 mm-1, the final R = 0.0366 and wR = 0.0899 for 5367 observed reflections with I > 2(I). The two clusters have also been characterized by elemental analysis, IR and 1H-NMR spectroscopy.
基金the grants from the State Key Program of China the National Natural Science Foundation of China (29871001 20071001) and the Committee of Education of Anhui province
文摘A novel complex [Cd2(phen)4(fca)2](ClO4)2(H2O)2 (fca = dianion of 3-ferrocenyl- 2-crotonic acid, phen = 1,10-phenanthroline) has been synthesized and characterized by X-ray single-crystal structure analysis. It crystallizes in triclinic system, space group P?with a = 11.6297(5), b = 12.5165(5), c = 13.8986(6) ? a = 63.345(1), b = 87.747(1), g = 71.862(1), V = 1706.20(1) ?, Z = 1, Dc = 1.673 g/cm3, F(000) = 868 and m(MoKa) = 1.185 mm-1 (l = 0.71073 ). R = 0.0800 and wR = 0.1793 for 7653 observed reflections (I > 2s(I)). The structure consists of a dinuclear cation [Cd2(phen)4(fca)2]2+, two discrete perchlorate anions and two water molecules. The cationic part of the complex shows a tetrametallic core in which two fca groups act as the (O, O) bridging ligands between two cadmium(Ⅱ) ions with a distorted octahedral environment. The Cd…Cd intradimer distance is 4.128 ?
文摘The reduction of an aqueous solution of sodium molybdate by iron powder at low pH value (～0.83), in the presence of ethylenediaminetetraacetate (EDTA) ligand, gives the title compound [Fe(H 2O) 6][Mo 2O 4(EDTA)]·5H 2O 1, which was characterized by elemental analysis, IR and X ray single crystal diffraction techniques. Compound 1 crystallizes in monoclinic system, space group P2 1/c, C 10 H 34 N 2FeMo 2O 23 , M r=798.12, a=8.781(1), b=14.081(1), c=21.353(1) , β= 92\^688(1)°, V = 2637.2(3) 3, Z = 4, D c = 2.010 g·cm -3 , μ = 1.579 mm -1 , F (000)=1608, the final R =0.0530 and wR =0.1271 for 3312 observed reflections. The binuclear oxomolybdenum(V) anion and the six coordinated Fe(II) cation are linked to infinite three dimensional network through several hydrogen bonds towards different directions between crystal waters, Fe(II) cation and Mo(V) anion.
文摘A new cyano-bridged Gadolinium^(Ⅲ)-Iron^(Ⅲ)complex{[Gd(DMF)_(3)(DMSO)(H_(2)O)_(3)]2H_(2)0(DMF=N,N·-dimethylformamide;DMSO=dimethylsulfoxidel}was synthesized by the grinding reaction method,.It crysta-]llizes in the triclinic.,space group P1 with ceIl parameters:a=O.90363(2)nm,b=1.25078(3)nm,c=1.41303(1)nm,穋m^(-3),Z=2,Mr=756.72,F(000)=760,Ⅲ)and the approxi-mately oriented octahedrally sixfold-coordinated Fe(Ⅲ)are linked by a cyano-bridge group to construct a dinuclear compound.The{[Gd(DMF)_(3)(DMSO)(H_(2)O)_(3)](Ⅲ)-Fe(Ⅲ)interaction is antiferromagnetic.CCDC:223430.
基金financially supported by the National Natural Science Foundation of ChinaMinistry of Education of China+1 种基金Beijing Municipal Commission of EducationFundamental Research Funds for the Central Universities
文摘Four cyanide-bridged heterometallic complexes { [CuPb（L1）][FenI（bpb）（CN）2] }2-（C104）2.2H20.2CH3CN （1）, { [CuPb（LI）]2[FeII （CN）6]（HzO）z}＇10H20 （2）, {[Cu2（L2）][Fent（bpb）（CN）2]2}＇2H20＇2CH3OH （3） and {[Cu2（L2）]3[FeIII（CN）6]z（H20）2}-10H20 （4） have been synthesized by treating K[Fem（bpb）（CN）2] [bpb2-=l,2-bis（pyridine-2-carboxamido）benzenate] and K3[Feln（CN）]6 with dinuc[ear compartmental macrocyclic Schiff-base complexes [CuPh（LI）].（C104）2 or [Cu2（L2）]-（CIO4）2, in which H2LJ was derived from 2,6-diformyl-4-methyl-phenol, ethylenediamine, and diethylenetriamine in the molar ratio of 2：1：1 and H2L2 from 2,6-diformyl-4-methyl-phenol and propylenediamine in the molar ratio of 1：1. Single crystal X-ray diffraction analysis reveals that compound 1 displays a cyclic hexanuclear heterotrimetallic molecular structure with alternating [Fem（bpb）（CN）2]- and [CuPb（L＋）]2＋ units. Complex 2 is of a neutral dumb-bell-type pentanuclear molecular configuration consisting of one [Fe（CN）6]4- anion sandwiched in two [CuPu（L1）]2＋ cations, and the pentanuclear moieties are further connected by the hydro- gen bonding to give a 2D supramolecular framework. Heterobimetallic complex 3 is a tetranuclear molecule composed of a centrosymmetric [Cuz（L2）]2＋ segment and two terminal cyanide-containing blocks [Fetn（bpb）（CN）2]-. Octanuclear compound 4 is built from two [Fe（CN）6]3- anions sandwiched in the three [Cu2L2]2＋ cations. Investigation of their magnetic properties reveals the overall antiferromagnetic behavior in the series of complexes except 2.
基金supported by the Ministry of Science and Technology (2016YFA0203302)the National Natural Science Foundation of China (21634003, 51573027, 51673043, 21604012, 21805044 and 21875042)+1 种基金Shanghai Science and Technology Committee (16JC1400702, 17QA1400400, 18QA1400700 and 18QA1400800)SHMEC (2017-01-07-00-07-E00062)
文摘As an im portant branch of fiber-shaped energy storage devices, the fiber-shaped supercapacitor has been widely studied recently. However, it remains challenging to simultaneously achieve fast electron transport and excellent ion accessibility in one single fiber electrode of the fibershaped supercapacitor. Herein, a novel family of amphiphilic core-sheath structured carbon nanotube composite fibers has been developed and applied to the fiber-shaped supercapacitor to address the above challenge. The polyaniline-modified hydrophilic sheath of the composite fiber electrode effectively enhanced the electrochemical property via advancing ion accessibility, while Au-deposited hydrophobic core demonstrated improved electrical conductivity by fast electron supply. On the basis of a synergistic effect, a remarkable specific capacitance of 324 F cm^-3 at 0.5 A cm^-3 and greatly enhanced rate performance were achieved, i.e” a 79% retention (256 F cm 3) at 50 A cm^-3. The obtained fiber-shaped supercapacitor finally displayed remarkable energy and power densities of 7.2 mW h cm 3 and 10 W cm^-3, respectively. The strategy developed herein also presents a general pathway towards novel fiber electrodes for high-performance wearable devices.
基金supported by grants from the National Natural Science Foundation of China (90922032, 21171100, 21151001)Ministry of Education (IRT0927)
文摘Three new isostructural binuclear transition metal complexes with azido ion and 1,2-bis（3-（pyridin-2-yl）-lH-pyrazol-1- yl）ethane （bppe）, formulated as [M2（N3）2（bppe）2]（C104）2 （M = Co, 1; Ni, 2; Cu, 3）, were successfully synthesized. They were structurally and magnetically characterized. In 1-3, the double azido ions link two adjacent octahedral metal centers together in the end-to-on mode （EO）, with the M-NEo-M angles of 99.41°, 100.24° and 99.80°, respectively. The co-ligand bppe acts as terminal ligand to saturate the remaining coordination sites. The magnetic properties of 1-3 have been investigated in the tem- perature range of 2-300 K. Fitting of the magnetic susceptibility data revealed the occurrence of the strong ferromagnetic in- teractions [J = 26.32 cm-1 （1）, J = 38.23 cm-1 （2） and J = 139.83 cm-1 （3）]. Density functional theory calculations have been performed on 1-3 to provide a magneto-structural correlation of the ferromagnetic behavior.
基金supported by the National Natural Science Foundation of China(21172272,21272291)
文摘G-quadruplexes comprise a class of secondary structures that are formed in guanine-rich sequences in eukaryotic genomes and play a crucial role in the regulation of many biological events.G-quadruplexes have become targets for anticancer drugs with high selectivity vs.duplex DNA and low cytotoxicity against normal cells.Natural products and their derivatives display polymorphism,structural complexity,and potent activity.It is,therefore,reasonable to seek ligands targeting G-quadruplexes from natural products.Recently,many successful examples have been reported,showing ligands with excellent anticancer activities.In this review,we summarized the development of research on natural products and derivatives that target G-quadruplex structures in an effort to guide future studies.
