Novel polymeric Cu<sup>2+</sup> complexes derived from the reaction of cyanoacetylhydrazine (<strong>CAH</strong>;<strong>L</strong>) with CuCl<sub>2</sub>•2H<sub>...Novel polymeric Cu<sup>2+</sup> complexes derived from the reaction of cyanoacetylhydrazine (<strong>CAH</strong>;<strong>L</strong>) with CuCl<sub>2</sub>•2H<sub>2</sub>O in different solvents were synthesized and characterized. The isolated solid polymeric complexes were investigated using modern conventional physicochemical and spectral (IR, <sup>1</sup>H-NMR, UV-Vis. ESR, Raman), magnetic and thermal studies. The results revealed that <strong>CAH</strong> behaves in different ways towards the coordination of the Cu<sup>2+</sup> ion. The promotion of solvents to the cyano group was discussed on the basis of the solvent and the Cu<sup>2+</sup> ion used. Magnetic and spectral studies suggest octahedral geometry is proposed for the Cu<sup>2+</sup> complexes. EPR studies indicate the existence of polymeric complexes depending on the results of <i>g</i>-values. The results suggest that the number of copper atoms ranges from three to twelve atoms. The molecular modeling is drawn and some chemical characteristics are calculated such as chemical reactivity and energy components are investigated between the different types of the ligands.展开更多
Background:Pig organ xenotransplantation is a potential solution for the severe organ shortage in clinic,while immunogenic genes need to be eliminated to improve the immune compatibility between humans and pigs.Curren...Background:Pig organ xenotransplantation is a potential solution for the severe organ shortage in clinic,while immunogenic genes need to be eliminated to improve the immune compatibility between humans and pigs.Current knockout strategies are mainly aimed at the genes causing hyperacute immune rejection(HAR)that occurs in the first few hours while adaptive immune reactions orchestrated by CD4 T cell thereafter also cause graft failure,in which process the MHCⅡmolecule plays critical roles.Methods:Thus,we generate a 4-gene(GGTA1,CMAH,β4GalNT2,and CIITA)knockout pig by CRISPR/Cas9 and somatic cell nuclear transfer to compromise HAR and CD4 T cell reactions simultaneously.Results:We successfully obtained 4KO piglets with deficiency in all alleles of genes,and at cellular and tissue levels.Additionally,the safety of our animals after gene editing was verified by using whole-genome sequencing and karyotyping.Piglets have survived for more than one year in the barrier,and also survived for more than 3 months in the conventional environment,suggesting that the piglets without MHCⅡcan be raised in the barrier and then gradually mated in the conventional environment.Conclusions:4KO piglets have lower immunogenicity,are safe in genomic level,and are easier to breed than the model with both MHCⅠandⅡdeletion.展开更多
Photoinduced electron transfer reaction between the excited state ruthenium (II) polypyridyl complexes and quinones has been investigated in cetyltrimethylammonium bromide using luminescent quenching techniques. The c...Photoinduced electron transfer reaction between the excited state ruthenium (II) polypyridyl complexes and quinones has been investigated in cetyltrimethylammonium bromide using luminescent quenching techniques. The complexes have the absorption and emission maximum in the range 452 - 468 nm and 594 - 617 nm respectively. The static nature of quenching is confirmed from the ground state absorption studies. The association constants for the complexes with quinones are calculated from the Benesi-Hildebrand plots using absorption spectral data. The value of quenching rate constant (kq) is highly sensitive to the nature of the ligand and the quencher, the medium, structure and size of the quenchers. Compared to the aqueous medium, the electron transfer rate is altered in CTAB medium. The oxidative nature of the quenching is confirmed by the formation of Ru3+ ion and quinone anion radical.展开更多
l,l'-biisoquinoline can coordinate with ruthenfum(Ⅱ) to form a new series of mononuclear complexes and the electronic absorption of these complexes were measured and reasonably assigned.
The synthesis and characterization of several hexa – coordinated Ru(II) complexes of the type [Ru(CO)(B)(L)] (B = PPh3/AsPh3/py/pip;L = di-basic tetradentate ligand derived from the condensation of isatin with diamin...The synthesis and characterization of several hexa – coordinated Ru(II) complexes of the type [Ru(CO)(B)(L)] (B = PPh3/AsPh3/py/pip;L = di-basic tetradentate ligand derived from the condensation of isatin with diamines) were reported. IR, electronic, 1H- NMR, 31P-NMR of the complexes are discussed. An octahedral geometry has been tentatively proposed for all these complexes. The new complexes have been tested for the catalytic activity in the reaction of oxidation of alcohols in the presence of N-me- thylmorpholine–N-oxide as co-oxidant. The new complexes were also exhibited antimicrobial investigations.展开更多
Using two new flexible and functional nitronyl nitroxide radicals as ligands, two copper (II) complexes {[Cu(hfac)<sub>2</sub>]<sub>3</sub>(NITmPhO3Py)<sub>2</sub>}<sub>n...Using two new flexible and functional nitronyl nitroxide radicals as ligands, two copper (II) complexes {[Cu(hfac)<sub>2</sub>]<sub>3</sub>(NITmPhO3Py)<sub>2</sub>}<sub>n</sub> (1) and [Cu(hfac)<sub>2</sub><sub> </sub>(NIToPhO3Py)]<sub>2</sub> (2) (NITmPhO3Py = 2-[(3-methoxy-pyridinyl)phen-3-yl]- 4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide, NIToPhO3Py = 2-[(3-methoxy-pyridinyl)phen-2-ly]-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide, hfac = hexafluoroacetylacetone), have been characterized structurally and magnetically. The X-ray crystal analyses showed that complex 1 displayed a chain polymer structure which formed with {[Cu(hfac)<sub>2</sub>]<sub>3</sub>(NITmPhO3Py)<sub>2</sub>}<sub>n</sub> due to the cross-linking of two cyclic binuclear fragments {[Cu(hfac)<sub>2</sub>]<sub>2</sub>(NITmPhO3- Py)<sub>2</sub>} via the bridging unit [Cu(hfac)<sub>2</sub>];complex 2 presented a binuclear cyclic structure [Cu(hfac)<sub>2</sub>]<sub>2</sub>(NIToPhO3Py)<sub>2</sub>. The magnetic behaviors of the two complexes 1 and 2 have been investigated. Magnetic studies showed that antiferromagnetic interactions dominated in complex 1, while there existed ferromagnetic interactions between Cu(II) and coordinated NO group in complex 2.展开更多
This work was undertaken to see how Ru II complexes can be suitable for photodynamic therapy through theoretical prediction. For that, four Ru II complexes, α-RuCl<sub>2</sub>(Azpy)<sub>2</sub>...This work was undertaken to see how Ru II complexes can be suitable for photodynamic therapy through theoretical prediction. For that, four Ru II complexes, α-RuCl<sub>2</sub>(Azpy)<sub>2</sub>, , and were used in unrestricted state by providing with no more energy than 2.68 eV. The unrestricted state allows the complex molecule to display each of its electrons in one orbital. All the calculations such as optimization, frequency and TD-DFT calculations were performed at WB97XD/Lanl2dz level. It resulted from this investigation that Ru II complexes are active for both mechanisms suitable for photodynamic therapy in presence or absence of <sup>3</sup>O<sub>2</sub>. Moreover, this reaction was assumed to take place only with Guanine DNA base as demonstrated in literature. Therefore, Guanine is admitted as the base most reacting with ruthenium complexes for photodynamic therapy. This work confirms our prediction regarding metallic complexes that are assumed to be photosensitized in condition that an electron must be isolated to favor the excitation. Nevertheless, Ru II complexes are found suitable for superficial therapy while Ru III must be active for deep therapy.展开更多
The catalysis of olefin polymerization through the chain-walking process is a subject of great interest. In this contribution, the successful synthesis of a Brookhart-type unsymmetrical α-diimine nickel catalyst Ni, ...The catalysis of olefin polymerization through the chain-walking process is a subject of great interest. In this contribution, the successful synthesis of a Brookhart-type unsymmetrical α-diimine nickel catalyst Ni, which contains both dibenzhydryl and phenyl groups, was determined by X-ray crystallography. The compound has a pseudo-tetrahedral geometry at the Ni center, showing pseudo-C2-symmetry. Upon activation with modified methylaluminoxane (MMAO), Ni1 exhibits high catalytic activity up to 1.02 × 107 g PE (mol Ni h)−1 toward ethylene polymerization, enabling the synthesis of high molecular weight branched polyethylene. The molecular weights and branching densities could be tuned over a very wide range. The polymerization results indicated the possibility of precise microstructure control, depending on the polymerization temperature. The branching densities were decreased with increasing the polymerization temperature.展开更多
The ground and the lowest-lying triplet excited state geometries, electronic structures, and spectroscopic properties of three mixed-ligand Ru(II) complexes [Ru(terpy)(phen)X]+ (terpy=2,2',6',2″-terpyridine...The ground and the lowest-lying triplet excited state geometries, electronic structures, and spectroscopic properties of three mixed-ligand Ru(II) complexes [Ru(terpy)(phen)X]+ (terpy=2,2',6',2″-terpyridine, phen=l,10-phenanthroline, and X=-C-=CH (1), X=Cl (2), X-CN (3)) were investigated theoretically using the density functional theory method. The ground and excited state geometries have been fully optimized at the B3LYP/LanL2DZ and UB3LYP/LanL2DZ levels, respectively. The absorption and emission spectra of the com- plexes in CHaCN solutions were calculated by time-dependent density functional theory with the PCM solvent model. The calculated bond lengths of Ru-C, Ru-N, and Ru-Cl in the ground state agree well with the corresponding experimental results. The highest occupied molecular orbital were dominantly localized on the Ru atom and monodentate X ligand for 1 and 2, Ru atom and terpy ligand for a, while the lowest unoccupied molecular orbital were π*(terpy) type orbital. Therefore, the lowest-energy absorptions of 1 and 2 at 688 and 631 nln are attributed to a dyz (Ru)+Tr/p(X)--π* (terpy) transition with MLCT/XLCT (metal-to-ligand charge transfer/X ligand to terpy ligand charge transfer) character, whereas that of 3 at 529 nm is related to a dyz (Ru)+π(terpy)-π* (terpy) transition with MLCT and ILCT transition character. The calculated phosphorescence of three complexes at 1011 nm (1), 913 nm (2), and 838 nm (3) have similar transition properties to that of the lowest-lying absorption. It is shown that the lowest lying absorptions and emissions transition character of these Ru(II) complexes can be tuned by changing the electron-withdrawing ability of the monodentate ligand.展开更多
The interactions between human erythrocyte spectrin(SP) and Pt(II) complexes with different composition and configuration were studied by fluorescence and circular dichroism spectra. The results showed that there are ...The interactions between human erythrocyte spectrin(SP) and Pt(II) complexes with different composition and configuration were studied by fluorescence and circular dichroism spectra. The results showed that there are 4.7×10 2 binding sites of cisplatin(CDDP) in a spectrin tetramer(SPT). Among them, about 70 sites with apparent binding constant K 1】3.47×10 6 were of highest affinity, 1.8×10 2 sites with K 2 = 3.47×10 6 were of high affinity, and other 2.2×10 2 sites with K 3 = 8.77×10 5 were of low affinity. The conformation change of spectrin, depending on the concentration of Pt(II) complex and molar ratio(R) of Pt(II) complex to spectrin, was induced by the binding of Pt(II) complexes. It indicated that the interaction of both CDDP and cis diaquodiamine platinum(DADP) with SP followed a two step first order kinetic process in the first stage (1 h), and the kinetic constants were determined. In the second stage, the induced conformation change, polymerization and depolymerization of SP were probably involved. It was noticed that in the reaction of SP and Pt(II) complexes with 1,2 cyclohexanediammine isomers as chiral carrier ligand, stereo matching played a more important role than the affinity of Pt(II) to thiol groups of SP.展开更多
A series of mononuclear complexes and unsymmetric dinuclear alkynylplatinum(II)terpyridine complexes with oligo(paraphenylene ethynylene)(OPE)-derived backbone with a variation of the lengths of alkoxy chains and OPE ...A series of mononuclear complexes and unsymmetric dinuclear alkynylplatinum(II)terpyridine complexes with oligo(paraphenylene ethynylene)(OPE)-derived backbone with a variation of the lengths of alkoxy chains and OPE backbones was synthesized.The morphological properties,packing lattice and gelation behaviors of the mononuclear complexes were systematically studied,and the thermodynamic parameters and packing lattices of the dinuclear complexes were also investigated,providing further insights into the roles of the non-covalent interactions and their delicate balance in constructing sophisticated supramolecular architectures.Metallogel and nanotube formation have been observed upon a delicate control of the intermolecular interactions by altering the lengths and structural dimensions of the complexes.展开更多
The platinum (II) complexes of the [Pt (N4,N7-Ribavirin) (DMSO) Cl], [Pt (N4,N7-De-oxyribavirin) (DMSO) Cl] were obtained by the reactions of cis-[Pt (DMSO)2 Cl2] and K[Pt (DMSO) Cl3] with 1-??-D-ribofuranosyl-1,2,4-t...The platinum (II) complexes of the [Pt (N4,N7-Ribavirin) (DMSO) Cl], [Pt (N4,N7-De-oxyribavirin) (DMSO) Cl] were obtained by the reactions of cis-[Pt (DMSO)2 Cl2] and K[Pt (DMSO) Cl3] with 1-??-D-ribofuranosyl-1,2,4-triazole-3-carboxamide (Ribavirin) and its deoxy-analogue (deoxyribavirin). The preparation of 1-(2'-deoxy-?-D-ribofuranosyl) -1,2,4-triazole-3-carboxamide was also performed through a four-step procedure, protection of 3', 5'-dihydroxyl group of Ribavirin with 1,3-dichloro-1,1,3,3-tetraisopropyldisiloxane (TPDS-Cl), phenoxythio-carbonylation of the 2'-hydroxyl group of 3', 5'-O-TPDS-Ribavirin with phenoxythiocarbonyl-chloride (PTC-Cl), reduction of 2′-O-phenoxythiocarbonyl ester of 3', 5'-O-TPDS-Ribavirin with tri-n-butyltin hydride and AIBN, deprotection of 3', 5'-O-TPDS-Ribavirin with tetrabutylammon-ium fluoride in THF.展开更多
An alkaline earth metal-organic framework [Ba(Hsip)(H2O)4]n (1, NaH2sip = 5-sulfoisophthalic acid sodium) has been constructed, and characterized by single-crystal X-ray diffraction. In complex 1, each Ba(II) ...An alkaline earth metal-organic framework [Ba(Hsip)(H2O)4]n (1, NaH2sip = 5-sulfoisophthalic acid sodium) has been constructed, and characterized by single-crystal X-ray diffraction. In complex 1, each Ba(II) atom coordinates to one ligand Hsip3- and four water molecules with a distorted nine-coordinated monocapped tetragonal antiprism geometry. Each Hsip2- anion acts as a μ3-bridging ligand, in which two carboxylate groups adopt the same bidentate chelating coordinating model and the sulfonate group takes a monodentate coordinating model, resulting in a wave-like two-dimensional network with a (6, 3) topological structure. The two-dimensional networks are further linked by O–H···O to form a three-dimensional structure. Luminescent property and thermal stability of complex 1 are investigated. 1 belongs to the orthorhombic system, space group Pna21 with a = 7.3333(2), b = 16.7044(3), c = 10.4817(2), Z = 4, V = 1283.99(5)3, Mr = 453.58, Dc = 2.346 g/cm3, F(000) = 880, μ = 3.314 mm–1, the final R = 0.0261 and wR = 0.0592 for 2425 observed reflections with I 2σ(I).展开更多
The complex [Ni(L)(N3)2](H_2O (L=N,N(-Bis(2-pyridylaldehyde) condensation 1,3-diaminopropane) was synthesized by the reaction of NiCl2(6H_2O with 2-pyridylaldehyde and 1,3-diaminopropane and sodium azide in the ethan...The complex [Ni(L)(N3)2](H_2O (L=N,N(-Bis(2-pyridylaldehyde) condensation 1,3-diaminopropane) was synthesized by the reaction of NiCl2(6H_2O with 2-pyridylaldehyde and 1,3-diaminopropane and sodium azide in the ethanol. A single-crystal X-ray study shows that the complex is a six-coordinated nickel (II) with an octahedral environment compound (C15H18N10NiO). The crystal is orthogonal, space group Pbca, with unit cell parameters: a = 13.577(3), b = 15.261(3), c = 17.554(4) ?, V= 3637(1) ?3, Z=8, Mr=413.10, Dc=1.509 g/cm3, ( = 1.096 mm-1, F(000) = 1712, T = 293(2)K, R = 0.0411, wR = 0.1048 for 2888 reflections with I >2( (I). The distances between Ni and N atoms (N(1), N(2), N(3), N(4)) range from 2.050(2) to 2.140(2)?. The distances of Ni-N(5) and Ni-N(8) are 2.115(3) and 2.133(3)?, respectively. The solvent molecule H_2O(O(1)) is linked by hydrogen bonds with O(1) and N(5) and N(8) atoms. Their distances are 2.881(+x, +y, +z) and 2.893(0.5+x, y, 0.5+z)?, respectively.展开更多
Oxygenation constants and thermodynamic parameters DeltaH degrees and DeltaS degrees of cobalt (II) complexes with bis-(furaldehyde) Schiff bases (1, 2, 3, 4)were obtained by mearsuring saturated dioxygen uptake of th...Oxygenation constants and thermodynamic parameters DeltaH degrees and DeltaS degrees of cobalt (II) complexes with bis-(furaldehyde) Schiff bases (1, 2, 3, 4)were obtained by mearsuring saturated dioxygen uptake of these complexes in pyridine at different temperature. These complexes could activate molecular oxygen and were used as catalysts in cyclohexene oxidation. The influence of ligand structure on the dioxygen affinity and catalytic activity of the complexes were discussed.展开更多
The title complex [Cu2(bipy)2(Hpht)2Cl](Hpht) (bipy = 2,2?-bipyridine, H2pht = o-phthalic acid) has been synthesized in the NaOH aqueous solution of CuCl2, Gd(NO3)3, bipy and H2pht, and its crystal structure was det...The title complex [Cu2(bipy)2(Hpht)2Cl](Hpht) (bipy = 2,2?-bipyridine, H2pht = o-phthalic acid) has been synthesized in the NaOH aqueous solution of CuCl2, Gd(NO3)3, bipy and H2pht, and its crystal structure was determined by single-crystal X-ray diffraction method. It crys- tallizes in triclinic, space group P1, C44H31ClCu2N4O12, Mr = 970.26, a = 8.175(2), b = 16.254(4), c = 16.946(4) ?, α = 62.966(6), β = 84.833(8), γ = 84.348(8)°, V = 1993.4(8) ?3, Z = 2, Dc = 1.616 g/cm3, F(000) = 988 and μ = 1.207 mm-1. The final R = 0.0429 and wR = 0.0843 for 5682 observed reflections with I > 2σ(I). Each copper(II) atom displays a distorted square-pyramidal geometry with two nitrogen atoms of one chelate 2,2?-bipy molecule, two oxygen atoms from two different bridging carboxylate groups of Hpht- and one bridging chloride atom occupying the apical position. The two copper(II) atoms are connected by a μ2-Cl atom and two bridging Hpht- ligands in a syn-syn coordination mode to form an isolated dinuclear unit. The molecular structure is extended to a one-dimensional wavy chain through hydrogen bonds. The title complex exhibits blue fluorescent emission at 443 nm (λex = 372 nm) in the solid state at room temperature.展开更多
文摘Novel polymeric Cu<sup>2+</sup> complexes derived from the reaction of cyanoacetylhydrazine (<strong>CAH</strong>;<strong>L</strong>) with CuCl<sub>2</sub>•2H<sub>2</sub>O in different solvents were synthesized and characterized. The isolated solid polymeric complexes were investigated using modern conventional physicochemical and spectral (IR, <sup>1</sup>H-NMR, UV-Vis. ESR, Raman), magnetic and thermal studies. The results revealed that <strong>CAH</strong> behaves in different ways towards the coordination of the Cu<sup>2+</sup> ion. The promotion of solvents to the cyano group was discussed on the basis of the solvent and the Cu<sup>2+</sup> ion used. Magnetic and spectral studies suggest octahedral geometry is proposed for the Cu<sup>2+</sup> complexes. EPR studies indicate the existence of polymeric complexes depending on the results of <i>g</i>-values. The results suggest that the number of copper atoms ranges from three to twelve atoms. The molecular modeling is drawn and some chemical characteristics are calculated such as chemical reactivity and energy components are investigated between the different types of the ligands.
基金National Key Research and Development Program,Grant/Award Number:2019YFA0903800,2021YFA0805701,2021YFA0805905 and 2022YFA1103603CAS Project for Young Scientists in Basic Research,Grant/Award Number:YSBR-012+2 种基金STI 2030-Major Project,Grant/Award Number:2023ZD0407503National Natural Science Foundation of China,Grant/Award Number:32071456 and 82241224Strategic Priority Research Program of the Chinese Academy of Sciences,Grant/Award Number:XDA16030000。
文摘Background:Pig organ xenotransplantation is a potential solution for the severe organ shortage in clinic,while immunogenic genes need to be eliminated to improve the immune compatibility between humans and pigs.Current knockout strategies are mainly aimed at the genes causing hyperacute immune rejection(HAR)that occurs in the first few hours while adaptive immune reactions orchestrated by CD4 T cell thereafter also cause graft failure,in which process the MHCⅡmolecule plays critical roles.Methods:Thus,we generate a 4-gene(GGTA1,CMAH,β4GalNT2,and CIITA)knockout pig by CRISPR/Cas9 and somatic cell nuclear transfer to compromise HAR and CD4 T cell reactions simultaneously.Results:We successfully obtained 4KO piglets with deficiency in all alleles of genes,and at cellular and tissue levels.Additionally,the safety of our animals after gene editing was verified by using whole-genome sequencing and karyotyping.Piglets have survived for more than one year in the barrier,and also survived for more than 3 months in the conventional environment,suggesting that the piglets without MHCⅡcan be raised in the barrier and then gradually mated in the conventional environment.Conclusions:4KO piglets have lower immunogenicity,are safe in genomic level,and are easier to breed than the model with both MHCⅠandⅡdeletion.
文摘Photoinduced electron transfer reaction between the excited state ruthenium (II) polypyridyl complexes and quinones has been investigated in cetyltrimethylammonium bromide using luminescent quenching techniques. The complexes have the absorption and emission maximum in the range 452 - 468 nm and 594 - 617 nm respectively. The static nature of quenching is confirmed from the ground state absorption studies. The association constants for the complexes with quinones are calculated from the Benesi-Hildebrand plots using absorption spectral data. The value of quenching rate constant (kq) is highly sensitive to the nature of the ligand and the quencher, the medium, structure and size of the quenchers. Compared to the aqueous medium, the electron transfer rate is altered in CTAB medium. The oxidative nature of the quenching is confirmed by the formation of Ru3+ ion and quinone anion radical.
文摘l,l'-biisoquinoline can coordinate with ruthenfum(Ⅱ) to form a new series of mononuclear complexes and the electronic absorption of these complexes were measured and reasonably assigned.
文摘The synthesis and characterization of several hexa – coordinated Ru(II) complexes of the type [Ru(CO)(B)(L)] (B = PPh3/AsPh3/py/pip;L = di-basic tetradentate ligand derived from the condensation of isatin with diamines) were reported. IR, electronic, 1H- NMR, 31P-NMR of the complexes are discussed. An octahedral geometry has been tentatively proposed for all these complexes. The new complexes have been tested for the catalytic activity in the reaction of oxidation of alcohols in the presence of N-me- thylmorpholine–N-oxide as co-oxidant. The new complexes were also exhibited antimicrobial investigations.
文摘Using two new flexible and functional nitronyl nitroxide radicals as ligands, two copper (II) complexes {[Cu(hfac)<sub>2</sub>]<sub>3</sub>(NITmPhO3Py)<sub>2</sub>}<sub>n</sub> (1) and [Cu(hfac)<sub>2</sub><sub> </sub>(NIToPhO3Py)]<sub>2</sub> (2) (NITmPhO3Py = 2-[(3-methoxy-pyridinyl)phen-3-yl]- 4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide, NIToPhO3Py = 2-[(3-methoxy-pyridinyl)phen-2-ly]-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide, hfac = hexafluoroacetylacetone), have been characterized structurally and magnetically. The X-ray crystal analyses showed that complex 1 displayed a chain polymer structure which formed with {[Cu(hfac)<sub>2</sub>]<sub>3</sub>(NITmPhO3Py)<sub>2</sub>}<sub>n</sub> due to the cross-linking of two cyclic binuclear fragments {[Cu(hfac)<sub>2</sub>]<sub>2</sub>(NITmPhO3- Py)<sub>2</sub>} via the bridging unit [Cu(hfac)<sub>2</sub>];complex 2 presented a binuclear cyclic structure [Cu(hfac)<sub>2</sub>]<sub>2</sub>(NIToPhO3Py)<sub>2</sub>. The magnetic behaviors of the two complexes 1 and 2 have been investigated. Magnetic studies showed that antiferromagnetic interactions dominated in complex 1, while there existed ferromagnetic interactions between Cu(II) and coordinated NO group in complex 2.
文摘This work was undertaken to see how Ru II complexes can be suitable for photodynamic therapy through theoretical prediction. For that, four Ru II complexes, α-RuCl<sub>2</sub>(Azpy)<sub>2</sub>, , and were used in unrestricted state by providing with no more energy than 2.68 eV. The unrestricted state allows the complex molecule to display each of its electrons in one orbital. All the calculations such as optimization, frequency and TD-DFT calculations were performed at WB97XD/Lanl2dz level. It resulted from this investigation that Ru II complexes are active for both mechanisms suitable for photodynamic therapy in presence or absence of <sup>3</sup>O<sub>2</sub>. Moreover, this reaction was assumed to take place only with Guanine DNA base as demonstrated in literature. Therefore, Guanine is admitted as the base most reacting with ruthenium complexes for photodynamic therapy. This work confirms our prediction regarding metallic complexes that are assumed to be photosensitized in condition that an electron must be isolated to favor the excitation. Nevertheless, Ru II complexes are found suitable for superficial therapy while Ru III must be active for deep therapy.
文摘The catalysis of olefin polymerization through the chain-walking process is a subject of great interest. In this contribution, the successful synthesis of a Brookhart-type unsymmetrical α-diimine nickel catalyst Ni, which contains both dibenzhydryl and phenyl groups, was determined by X-ray crystallography. The compound has a pseudo-tetrahedral geometry at the Ni center, showing pseudo-C2-symmetry. Upon activation with modified methylaluminoxane (MMAO), Ni1 exhibits high catalytic activity up to 1.02 × 107 g PE (mol Ni h)−1 toward ethylene polymerization, enabling the synthesis of high molecular weight branched polyethylene. The molecular weights and branching densities could be tuned over a very wide range. The polymerization results indicated the possibility of precise microstructure control, depending on the polymerization temperature. The branching densities were decreased with increasing the polymerization temperature.
文摘The ground and the lowest-lying triplet excited state geometries, electronic structures, and spectroscopic properties of three mixed-ligand Ru(II) complexes [Ru(terpy)(phen)X]+ (terpy=2,2',6',2″-terpyridine, phen=l,10-phenanthroline, and X=-C-=CH (1), X=Cl (2), X-CN (3)) were investigated theoretically using the density functional theory method. The ground and excited state geometries have been fully optimized at the B3LYP/LanL2DZ and UB3LYP/LanL2DZ levels, respectively. The absorption and emission spectra of the com- plexes in CHaCN solutions were calculated by time-dependent density functional theory with the PCM solvent model. The calculated bond lengths of Ru-C, Ru-N, and Ru-Cl in the ground state agree well with the corresponding experimental results. The highest occupied molecular orbital were dominantly localized on the Ru atom and monodentate X ligand for 1 and 2, Ru atom and terpy ligand for a, while the lowest unoccupied molecular orbital were π*(terpy) type orbital. Therefore, the lowest-energy absorptions of 1 and 2 at 688 and 631 nln are attributed to a dyz (Ru)+Tr/p(X)--π* (terpy) transition with MLCT/XLCT (metal-to-ligand charge transfer/X ligand to terpy ligand charge transfer) character, whereas that of 3 at 529 nm is related to a dyz (Ru)+π(terpy)-π* (terpy) transition with MLCT and ILCT transition character. The calculated phosphorescence of three complexes at 1011 nm (1), 913 nm (2), and 838 nm (3) have similar transition properties to that of the lowest-lying absorption. It is shown that the lowest lying absorptions and emissions transition character of these Ru(II) complexes can be tuned by changing the electron-withdrawing ability of the monodentate ligand.
文摘The interactions between human erythrocyte spectrin(SP) and Pt(II) complexes with different composition and configuration were studied by fluorescence and circular dichroism spectra. The results showed that there are 4.7×10 2 binding sites of cisplatin(CDDP) in a spectrin tetramer(SPT). Among them, about 70 sites with apparent binding constant K 1】3.47×10 6 were of highest affinity, 1.8×10 2 sites with K 2 = 3.47×10 6 were of high affinity, and other 2.2×10 2 sites with K 3 = 8.77×10 5 were of low affinity. The conformation change of spectrin, depending on the concentration of Pt(II) complex and molar ratio(R) of Pt(II) complex to spectrin, was induced by the binding of Pt(II) complexes. It indicated that the interaction of both CDDP and cis diaquodiamine platinum(DADP) with SP followed a two step first order kinetic process in the first stage (1 h), and the kinetic constants were determined. In the second stage, the induced conformation change, polymerization and depolymerization of SP were probably involved. It was noticed that in the reaction of SP and Pt(II) complexes with 1,2 cyclohexanediammine isomers as chiral carrier ligand, stereo matching played a more important role than the affinity of Pt(II) to thiol groups of SP.
基金funding administered by The University of Hong Kong for supporting the Electrospray Ionization Quadrupole Time-of-Flight Mass Spectrometry Facilities under the Support for Interdisciplinary Research in Chemical Sciencefinancially supported by the General Research Fund(GRF)from the Research Grants Council of Hong Kong Special Administrative Region,P.R.China(HKU 17302723)and CAS-Croucher Funding Scheme for Joint Laboratories on Molecular Functional Materials for Electronics,Switching and Sensing+2 种基金Funding support from the Innovation Technology Commission to the State Key Laboratory of Synthetic Chemistry is acknowledgedthe receipt of a Swire Scholarshipa Hong Kong Ph.D.Fellowship administered by the Research Grants Council of Hong Kong Special Administrative Region,P.R.China.
文摘A series of mononuclear complexes and unsymmetric dinuclear alkynylplatinum(II)terpyridine complexes with oligo(paraphenylene ethynylene)(OPE)-derived backbone with a variation of the lengths of alkoxy chains and OPE backbones was synthesized.The morphological properties,packing lattice and gelation behaviors of the mononuclear complexes were systematically studied,and the thermodynamic parameters and packing lattices of the dinuclear complexes were also investigated,providing further insights into the roles of the non-covalent interactions and their delicate balance in constructing sophisticated supramolecular architectures.Metallogel and nanotube formation have been observed upon a delicate control of the intermolecular interactions by altering the lengths and structural dimensions of the complexes.
文摘The platinum (II) complexes of the [Pt (N4,N7-Ribavirin) (DMSO) Cl], [Pt (N4,N7-De-oxyribavirin) (DMSO) Cl] were obtained by the reactions of cis-[Pt (DMSO)2 Cl2] and K[Pt (DMSO) Cl3] with 1-??-D-ribofuranosyl-1,2,4-triazole-3-carboxamide (Ribavirin) and its deoxy-analogue (deoxyribavirin). The preparation of 1-(2'-deoxy-?-D-ribofuranosyl) -1,2,4-triazole-3-carboxamide was also performed through a four-step procedure, protection of 3', 5'-dihydroxyl group of Ribavirin with 1,3-dichloro-1,1,3,3-tetraisopropyldisiloxane (TPDS-Cl), phenoxythio-carbonylation of the 2'-hydroxyl group of 3', 5'-O-TPDS-Ribavirin with phenoxythiocarbonyl-chloride (PTC-Cl), reduction of 2′-O-phenoxythiocarbonyl ester of 3', 5'-O-TPDS-Ribavirin with tri-n-butyltin hydride and AIBN, deprotection of 3', 5'-O-TPDS-Ribavirin with tetrabutylammon-ium fluoride in THF.
基金supported by the University Science Foundation of Anhui Province (No. KJ2011Z271)the Applied Chemistry Key Constructing Subject of Anhui Province (No. 200802187C)
文摘An alkaline earth metal-organic framework [Ba(Hsip)(H2O)4]n (1, NaH2sip = 5-sulfoisophthalic acid sodium) has been constructed, and characterized by single-crystal X-ray diffraction. In complex 1, each Ba(II) atom coordinates to one ligand Hsip3- and four water molecules with a distorted nine-coordinated monocapped tetragonal antiprism geometry. Each Hsip2- anion acts as a μ3-bridging ligand, in which two carboxylate groups adopt the same bidentate chelating coordinating model and the sulfonate group takes a monodentate coordinating model, resulting in a wave-like two-dimensional network with a (6, 3) topological structure. The two-dimensional networks are further linked by O–H···O to form a three-dimensional structure. Luminescent property and thermal stability of complex 1 are investigated. 1 belongs to the orthorhombic system, space group Pna21 with a = 7.3333(2), b = 16.7044(3), c = 10.4817(2), Z = 4, V = 1283.99(5)3, Mr = 453.58, Dc = 2.346 g/cm3, F(000) = 880, μ = 3.314 mm–1, the final R = 0.0261 and wR = 0.0592 for 2425 observed reflections with I 2σ(I).
文摘The complex [Ni(L)(N3)2](H_2O (L=N,N(-Bis(2-pyridylaldehyde) condensation 1,3-diaminopropane) was synthesized by the reaction of NiCl2(6H_2O with 2-pyridylaldehyde and 1,3-diaminopropane and sodium azide in the ethanol. A single-crystal X-ray study shows that the complex is a six-coordinated nickel (II) with an octahedral environment compound (C15H18N10NiO). The crystal is orthogonal, space group Pbca, with unit cell parameters: a = 13.577(3), b = 15.261(3), c = 17.554(4) ?, V= 3637(1) ?3, Z=8, Mr=413.10, Dc=1.509 g/cm3, ( = 1.096 mm-1, F(000) = 1712, T = 293(2)K, R = 0.0411, wR = 0.1048 for 2888 reflections with I >2( (I). The distances between Ni and N atoms (N(1), N(2), N(3), N(4)) range from 2.050(2) to 2.140(2)?. The distances of Ni-N(5) and Ni-N(8) are 2.115(3) and 2.133(3)?, respectively. The solvent molecule H_2O(O(1)) is linked by hydrogen bonds with O(1) and N(5) and N(8) atoms. Their distances are 2.881(+x, +y, +z) and 2.893(0.5+x, y, 0.5+z)?, respectively.
文摘Oxygenation constants and thermodynamic parameters DeltaH degrees and DeltaS degrees of cobalt (II) complexes with bis-(furaldehyde) Schiff bases (1, 2, 3, 4)were obtained by mearsuring saturated dioxygen uptake of these complexes in pyridine at different temperature. These complexes could activate molecular oxygen and were used as catalysts in cyclohexene oxidation. The influence of ligand structure on the dioxygen affinity and catalytic activity of the complexes were discussed.
基金This work was supported by the National Natural Science Foundation of China (20001007 20131020)+1 种基金and Natural Science Foundation of Fujian Province (2003I031 A0420002)
文摘The title complex [Cu2(bipy)2(Hpht)2Cl](Hpht) (bipy = 2,2?-bipyridine, H2pht = o-phthalic acid) has been synthesized in the NaOH aqueous solution of CuCl2, Gd(NO3)3, bipy and H2pht, and its crystal structure was determined by single-crystal X-ray diffraction method. It crys- tallizes in triclinic, space group P1, C44H31ClCu2N4O12, Mr = 970.26, a = 8.175(2), b = 16.254(4), c = 16.946(4) ?, α = 62.966(6), β = 84.833(8), γ = 84.348(8)°, V = 1993.4(8) ?3, Z = 2, Dc = 1.616 g/cm3, F(000) = 988 and μ = 1.207 mm-1. The final R = 0.0429 and wR = 0.0843 for 5682 observed reflections with I > 2σ(I). Each copper(II) atom displays a distorted square-pyramidal geometry with two nitrogen atoms of one chelate 2,2?-bipy molecule, two oxygen atoms from two different bridging carboxylate groups of Hpht- and one bridging chloride atom occupying the apical position. The two copper(II) atoms are connected by a μ2-Cl atom and two bridging Hpht- ligands in a syn-syn coordination mode to form an isolated dinuclear unit. The molecular structure is extended to a one-dimensional wavy chain through hydrogen bonds. The title complex exhibits blue fluorescent emission at 443 nm (λex = 372 nm) in the solid state at room temperature.