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
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 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
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
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
A new metal-organic complex Zn2(cbba)4(phen)2 (Hcbba = 2-(4'chlorine-ben- zoyl)benzoic acid, phen = 1,10-phenanthroline) 1 has been hydrothermally synthesized and structurally characterized by elemental analy...A new metal-organic complex Zn2(cbba)4(phen)2 (Hcbba = 2-(4'chlorine-ben- zoyl)benzoic acid, phen = 1,10-phenanthroline) 1 has been hydrothermally synthesized and structurally characterized by elemental analysis, IR, fluorescence spectrum and single-crystal X-ray diffraction. The compound crystallizes in orthorhombic, space group Pbcn with a = 12.0821(II), b = 18.3140(17), c = 30.961(3) A, V= 6850.7(11) A^3, C80H48C14N4O12Zn2, Mr= 1529.76, Dc = 1.483 g/cm^3,μ(MoKa) = 0.925 mm^-1, F(000) = 3120, Z = 4, the final R = 0.0559 and wR = 0.1146 for 3963 observed reflections (I〉 2σ(I)). In the crystal structure, the zinc atom is five-coordinated with three carboxylate oxygen atoms from three different cbba ligands and two nitrogen atoms from the phen ligand, showing a distorted square-pyramidal geometry. Furthermore, it exhibits a 3D supramolecular network through π-π interactions and shows yellow photoluminescent property at room temperature.展开更多
A new mixed-ligand nickel(Ⅱ) complex, [Ni(L)(DCA)(H2O)]·2H2O (L = C8H9N3, 2-aminomethyl-benzimidazole, DCA2- = 7-oxabicyclo[2,2,1]heptane-2,3-dicarboxylate, demethylcantharate, C8H8O5), has been synthe...A new mixed-ligand nickel(Ⅱ) complex, [Ni(L)(DCA)(H2O)]·2H2O (L = C8H9N3, 2-aminomethyl-benzimidazole, DCA2- = 7-oxabicyclo[2,2,1]heptane-2,3-dicarboxylate, demethylcantharate, C8H8O5), has been synthesized and characterized. The structure of the complex was determined by single-crystal X-ray diffraction. It is of monoclinic system, space group P21/c with a = 7.7211(7), b = 12.0799(12), c = 19.7867(19), β = 100.390(6)°, V = 1815.2(3) nm3, Dc = 1.625 g·cm-3, Ζ = 4, F(000) = 928, R = 0.0314 and wR = 0.0822. In addition, the interaction between the complex and DNA was studied by means of fluorescence spectra and viscosity. The results indicate that the complex binds to DNA by the mode of partial intercalation with the Stern-Volmer constants Ksv of 3.81 × 104 mol·L-1.展开更多
A new zinc(II) complex, Zn(2-NH2py)2Br2 (py=pyridine), has been synthesized, and its molecular structure has been confirmed by IR, elemental analysis and -ray crystal structure analysis. Its space group is P21/n with...A new zinc(II) complex, Zn(2-NH2py)2Br2 (py=pyridine), has been synthesized, and its molecular structure has been confirmed by IR, elemental analysis and -ray crystal structure analysis. Its space group is P21/n with Mr=413.43 (C10H12Br2N4Zn), a=7.435(2), b=12.865(3), c=14.186(4)? b=94.08(2)? V=1353.5(5) 3, Z=4, Dc=2.029 g/cm3, F(000)=328, ?2.378mm-1, R=0.0283, wR=0.0501. The total observed reflections with I≥2?I) were 5314, of which the independent reflections were 3106. The complex structure contains a distorted tetrahedron formed by four atoms coordinated to zinc atom, namely two bromide atoms and two nitrogen atoms. The two ZnBr bond lengths within one molecule, 2.3763(6) and 2.4002(5)? respectively, are not equal; and so are the two ZnN bond lengths, which are 2.031(2) and 2.044(2)?respectively. The calculation results using PM3 method through MOPAC software package in Chem 3D show that its first molecular hyperpolarizability b value is 5.210-30esu, which is comparable with that of p-nitroaniline. No bulk SHG effect has been detected due to the centrosymmetric space group.展开更多
A new dinuclear complex [Zn(dpa)(bipy)(H2O)]2 (dpa = 2,2'-diphenic acid, bipy = 2,2'-bipyridine) 1 has been hydrothermally synthesized and structurally characterized by elemental analysis, IR, fluorescence s...A new dinuclear complex [Zn(dpa)(bipy)(H2O)]2 (dpa = 2,2'-diphenic acid, bipy = 2,2'-bipyridine) 1 has been hydrothermally synthesized and structurally characterized by elemental analysis, IR, fluorescence spectrum and single-crystal X-ray diffraction. The complex crystallizes in monoclinic, space group P21/c with a = 10.960(2), b = 9.4841(18), c = 20.599(4), β = 104.452(3)o, V = 2073.4(7)3, C48H36N4O10Zn2, Mr = 959.55, Dc = 1.537 g/cm3, μ(MoKα) = 1.225 mm-1, F(000) = 984, Z = 2, the final R = 0.0364 and wR = 0.0843 for 2788 observed reflections (I 〉 2σ(I)). In the crystal structure, the zinc atom is five-coordinated with two carboxylate oxygen atoms from different dpas, one coordinated water molecule and two nitrogen atoms from bipy ligands, showing a slightly distorted triangular bipyramidal geometry. Furthermore, it exhibits a zero-dimensional network structure with a sixteen-membered ring and shows yellow photoluminescent property at room temperature.展开更多
Two homochiral mercury (1) and cadmium (2) complexes derived from chiral twisted biphenyl pyridine ligand (3,3'-bipyridine-5,5',6,6'-tetramethyl-2,2'-dimethoxy-1,1'-biphenyl) have been synthesized and chara...Two homochiral mercury (1) and cadmium (2) complexes derived from chiral twisted biphenyl pyridine ligand (3,3'-bipyridine-5,5',6,6'-tetramethyl-2,2'-dimethoxy-1,1'-biphenyl) have been synthesized and characterized by IR, microanalysis, TGA, UV-Vis, powder and single-crystal X-ray crystallography. Both 1 and 2 crystallize in orthorhombic space group P21212 with Z = 2. For 1, a = 14.2038(16), b = 14.3630(17), c = 7.0257(8), V = 1433.3(3)3, Mr = 878.91, Dc = 2.037 g/cm3, μ = 7.549 mm-1, F(000) = 824, the final GOF = 1.017, R = 0.0296 and wR = 0.0645 for 2925 observed reflections with I 2σ(I). For 2, a = 14.212(3), b = 14.392(3), c = 7.0498(14), V = 1442.0(5)3, Mr = 790.72, Dc = 1.821 g/cm3, μ = 2.924 mm–1, F(000) = 760, the final GOF = 1.075, R = 0.0340 and wR = 0.0834 for 3144 observed reflections with I 2σ(I). The crystal structures of 1 and 2 are isostructural and each adopts a two-dimensional supramolecular network which contains the C–H···π interactions.展开更多
A new dinuclear copper(II) complex ([Cu(C12H17N2O)(N3)]2, C24H34Cu2N10O2) has been synthesized and characterized by X-ray structure determination. It crystallizes in the monoclinic system, space group P21/c with a =...A new dinuclear copper(II) complex ([Cu(C12H17N2O)(N3)]2, C24H34Cu2N10O2) has been synthesized and characterized by X-ray structure determination. It crystallizes in the monoclinic system, space group P21/c with a = 18.529(4), b = 10.933(2), c = 14.534(3) ?, β = 111.07(3)°, V = 2748(1) ?3, Z = 4, Mr = 621.69, F(000) = 1288, Dc = 1.503 g/cm3 and μ(MoKα) = 1.590 mm?1. The structure was refined to R = 0.0647 and wR = 0.1846 for 4406 observed reflections (I > 2σ(I)). The asymmetric unit comprises two halfmolecules. The complex is a centrosymmetric dimmer in which the copper atoms are penta-coordinated by three coordination atoms from the corresponding tridentate Schiff base ligand and two bridging azide anions. The Cu(II)…Cu(II) average distance is 3.350(1) ?.展开更多
A discrete binuclear copper (II) complex containing Cu 2O 2 unit has been synthesized by the reaction of Cu (ClO 4) 2·6H 2O with 2 aminopyridine in the CH 3OH solution and characterized by X ray diffracti...A discrete binuclear copper (II) complex containing Cu 2O 2 unit has been synthesized by the reaction of Cu (ClO 4) 2·6H 2O with 2 aminopyridine in the CH 3OH solution and characterized by X ray diffraction study and IR spectroscopy. The crystal is monoclinic, space group: P2 1/n, with unit cell parameters: a=8.2952(2), b=18.4633(3), c=10.5049(2) . β=108.965(1)°, V=1521.56(5) 3, Z=2, C 22 H 30 N 8O 10 Cl 2Cu 2, M r =764.52, D c =1.669 Mg/m 3, F(000)=780, μ (Mo Kα )=8.60, T =293(2)K, final R=0.0623, wR =0.1536 for 2660 observed reflections with I>2.0σ(I ). The centrosymmetric complex Cu 2(CH 3O) 2(C 5H 6N 2) 4(ClO 4) 2 comprises a pair of Cu(II) atoms bridged by two methanoxo and N coordination 2 aminopyridine. The Cu(II)…Cu(II) distance is 3\^002(1).展开更多
The title complex Ni(C4H5NO4)(C7H6N2)31.75(H2O) (C25H26.5N7NiO5.75, Mr = 575.74) has been prepared and its crystal structure was determined by X-ray diffraction method. The crystal of this chiral complex belongs to mo...The title complex Ni(C4H5NO4)(C7H6N2)31.75(H2O) (C25H26.5N7NiO5.75, Mr = 575.74) has been prepared and its crystal structure was determined by X-ray diffraction method. The crystal of this chiral complex belongs to monoclinic, space group P21 with a = 13.208(1), b = 10.741(1), c = 19.398(1) ? b = 104.39(1)o, V = 2665.8(4) 3, Z = 4, Dc = 1.435 g/cm3, m(MoKa) = 0.780 mm-1 and F(000) = 1198. The final R = 0.0504 and wR = 0.1267 for 9159 observed reflections (I > 2s(I)), and R = 0.065 and wR = 0.1299 for 11006 independent reflections. The complex assumes a distorted octa- hedral coordinate geometry formed by one aspartate dianion and three benzimidazole ligands. The aspartate chelates to the Ni atom as a tridentate ligand. The lattice water molecules are hydrogen- bonded to the Ni complex molecule.展开更多
The title complex, C18H15N3NiO3, has been prepared and characterized by X-ray diffraction analysis. It crystallizes in the monoclinic system, space group Cc with a = 10.939(2), b = 22.909(5), c = 6.907(1) ?, β = 11...The title complex, C18H15N3NiO3, has been prepared and characterized by X-ray diffraction analysis. It crystallizes in the monoclinic system, space group Cc with a = 10.939(2), b = 22.909(5), c = 6.907(1) ?, β = 116.75(3)°, V = 1545.7(5) ?, Z = 4, Mr = 380.04, F(000) = 784, Dc = 1.633 g/cm3 and μ(MoKα) = 1.279 mm–1. The structure was refined to R = 0.0472 and wR = 0.0893 for 2571 observed reflections with I > 2σ(I). The absolute structure Flack parameter X is 0.01(2). In this crystal structure, strong face-to-face π-π stacking interactions between adjacent molecules lead to a one-dimensional chain structure.展开更多
A novel dinuclear complex with an empirical formula [Co2(1H-benzimidazole)4(1, 4-bdoa)2] (1,4-bdoa2– = benzene-1,4-dioxyacetate dianion) has been synthesized and characterized by elemental analysis, IR and single-cry...A novel dinuclear complex with an empirical formula [Co2(1H-benzimidazole)4(1, 4-bdoa)2] (1,4-bdoa2– = benzene-1,4-dioxyacetate dianion) has been synthesized and characterized by elemental analysis, IR and single-crystal X-ray diffraction. It crystallizes in monoclinic system, space group P21/c with a = 11.000(2), b = 19.385(4), c = 11.417(2) ?, β = 95.49(3)o, V = 2423.3(8) ?3, Z = 2, Mr = 1074.77, Dc = 1.473 g/cm3, μ = 0.760 mm–1, F(000) = 1108, the final R = 0.0645 and wR = 0.0714 for 3273 observed reflections (I > 2σ(I)). Two octahedrally coordinated Co(II) atoms are bridged by two 1,4-bdoa2– groups, generating a macrocyclic ring complex. The Co…Co separa- tion is 7.677(3) ?. An extended 3-D supramolecular network is formed through hydrogen bonds and weak π-π stacking interactions.展开更多
The cobalt(II) complex with (quinolin-8-yloxy)acetate, [CoCl(C11H8NO3)]n (1), has been prepared via the solvothermal method and characterized by IR, elemental analysis, UV- Vis diffuse-reflection spectra and s...The cobalt(II) complex with (quinolin-8-yloxy)acetate, [CoCl(C11H8NO3)]n (1), has been prepared via the solvothermal method and characterized by IR, elemental analysis, UV- Vis diffuse-reflection spectra and single-crystal X-ray diffraction analysis. Complex 1 is a novel carboxylate-bridged one-dimensional helical cobalt(II) polymer, and the Co(II) centre exhibits an approximately square pyramidal CoClNO3 coordination geometry. It crystallizes in monoclinic, space group P21/n, with a = 9.1594(10), b = 6.8864(7), c = 17.290(2) , β = 102.629(3)o, C11H8ClCoNO3, Mr = 296.56, V = 1064.2(2) 3, Z = 4, Dc = 1.851 g/cm3, F(000) = 596, μ = 1.856 mm-1, the final R = 0.0308 and wR = 0.0807. Interestingly, the chain complexes are assembled to form two-dimensional networks through intermolecular face-to-face π-π stacking interactions with the centroid-to-centroid distance of 3.559(1) and the dihedral angle of 8.4(1)° between the aromatic rings.展开更多
A new copper(II)-2,2'-biimidazole metal-organic POMs-supported compound [Cu(H2biim)2]{[Cu(H2biim)212[H10W12O44]}'8H2O (H2biim = 2,2'-biimidazole) has been success- fully synthesized under hydrothermal condi...A new copper(II)-2,2'-biimidazole metal-organic POMs-supported compound [Cu(H2biim)2]{[Cu(H2biim)212[H10W12O44]}'8H2O (H2biim = 2,2'-biimidazole) has been success- fully synthesized under hydrothermal conditions and characterized by single-crystal X-ray diffraction, IR spectroscopy, elemental analysis and TG. The crystal adopts space group Pi with a = 11.800(2), b = 13.437(3), c = 13.685(3) A, V = 1922.5(7) A3, D,. = 3.507 g/cm3, C36H62Cu3N24W12O52, M,. = 4059.92, F(000) = 1837,μ = 18.796 mm-1, Z = 1, R = 0.0579 and wR = 0.1465 for 8734 observed reflections (I 〉 2σ(I)). X-ray crystallography analysis exhibits that the title compound consists of one [H10W12044]6- polyanion and three [Cu(H2biim)2] units. And significant π-π stacking interactions and intermolecular O-H-,.O or N-H.'-O hydrogen-bonding interactions lead to a three-dimensional supramolecular framework. Thermal stability and magnetic property of the complex have also been investigated.展开更多
Three stable 4-substituted pyridine-based ruthenium(II)complexes[RuCl2(PPh3)L](L=4-R-2,6-bis (diethylaminomethylene)pyridine,R=Br,H or allyloxy)were synthesized.The catalytic activities of the complexes toward...Three stable 4-substituted pyridine-based ruthenium(II)complexes[RuCl2(PPh3)L](L=4-R-2,6-bis (diethylaminomethylene)pyridine,R=Br,H or allyloxy)were synthesized.The catalytic activities of the complexes toward transfer hydrogenation from alcohols to ketones were investigated.The electronic effects of the para-substituent in the pyridyl ring were probed and we found that the electron-donating group increased the catalytic activity.The result suggests that an electron-donating group is probably preferential for linking the catalytic ruthenium complex and the chemically inert supporting molecules such as a carbosilane dendrimer.展开更多
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 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.
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.
基金supported by the Science and Technology Research Projects of the Education Department of Jilin Province (No. 2011. 459)
文摘A new metal-organic complex Zn2(cbba)4(phen)2 (Hcbba = 2-(4'chlorine-ben- zoyl)benzoic acid, phen = 1,10-phenanthroline) 1 has been hydrothermally synthesized and structurally characterized by elemental analysis, IR, fluorescence spectrum and single-crystal X-ray diffraction. The compound crystallizes in orthorhombic, space group Pbcn with a = 12.0821(II), b = 18.3140(17), c = 30.961(3) A, V= 6850.7(11) A^3, C80H48C14N4O12Zn2, Mr= 1529.76, Dc = 1.483 g/cm^3,μ(MoKa) = 0.925 mm^-1, F(000) = 3120, Z = 4, the final R = 0.0559 and wR = 0.1146 for 3963 observed reflections (I〉 2σ(I)). In the crystal structure, the zinc atom is five-coordinated with three carboxylate oxygen atoms from three different cbba ligands and two nitrogen atoms from the phen ligand, showing a distorted square-pyramidal geometry. Furthermore, it exhibits a 3D supramolecular network through π-π interactions and shows yellow photoluminescent property at room temperature.
基金Supported by the Natural Science Foundation of Zhejiang Province (Y407301)
文摘A new mixed-ligand nickel(Ⅱ) complex, [Ni(L)(DCA)(H2O)]·2H2O (L = C8H9N3, 2-aminomethyl-benzimidazole, DCA2- = 7-oxabicyclo[2,2,1]heptane-2,3-dicarboxylate, demethylcantharate, C8H8O5), has been synthesized and characterized. The structure of the complex was determined by single-crystal X-ray diffraction. It is of monoclinic system, space group P21/c with a = 7.7211(7), b = 12.0799(12), c = 19.7867(19), β = 100.390(6)°, V = 1815.2(3) nm3, Dc = 1.625 g·cm-3, Ζ = 4, F(000) = 928, R = 0.0314 and wR = 0.0822. In addition, the interaction between the complex and DNA was studied by means of fluorescence spectra and viscosity. The results indicate that the complex binds to DNA by the mode of partial intercalation with the Stern-Volmer constants Ksv of 3.81 × 104 mol·L-1.
基金This work was financed by the National Key Fundamental Research Program of China.
文摘A new zinc(II) complex, Zn(2-NH2py)2Br2 (py=pyridine), has been synthesized, and its molecular structure has been confirmed by IR, elemental analysis and -ray crystal structure analysis. Its space group is P21/n with Mr=413.43 (C10H12Br2N4Zn), a=7.435(2), b=12.865(3), c=14.186(4)? b=94.08(2)? V=1353.5(5) 3, Z=4, Dc=2.029 g/cm3, F(000)=328, ?2.378mm-1, R=0.0283, wR=0.0501. The total observed reflections with I≥2?I) were 5314, of which the independent reflections were 3106. The complex structure contains a distorted tetrahedron formed by four atoms coordinated to zinc atom, namely two bromide atoms and two nitrogen atoms. The two ZnBr bond lengths within one molecule, 2.3763(6) and 2.4002(5)? respectively, are not equal; and so are the two ZnN bond lengths, which are 2.031(2) and 2.044(2)?respectively. The calculation results using PM3 method through MOPAC software package in Chem 3D show that its first molecular hyperpolarizability b value is 5.210-30esu, which is comparable with that of p-nitroaniline. No bulk SHG effect has been detected due to the centrosymmetric space group.
基金Supported by the Science and Technology Research Projects of the Education Office of Jilin Province (No. 2009. 272)
文摘A new dinuclear complex [Zn(dpa)(bipy)(H2O)]2 (dpa = 2,2'-diphenic acid, bipy = 2,2'-bipyridine) 1 has been hydrothermally synthesized and structurally characterized by elemental analysis, IR, fluorescence spectrum and single-crystal X-ray diffraction. The complex crystallizes in monoclinic, space group P21/c with a = 10.960(2), b = 9.4841(18), c = 20.599(4), β = 104.452(3)o, V = 2073.4(7)3, C48H36N4O10Zn2, Mr = 959.55, Dc = 1.537 g/cm3, μ(MoKα) = 1.225 mm-1, F(000) = 984, Z = 2, the final R = 0.0364 and wR = 0.0843 for 2788 observed reflections (I 〉 2σ(I)). In the crystal structure, the zinc atom is five-coordinated with two carboxylate oxygen atoms from different dpas, one coordinated water molecule and two nitrogen atoms from bipy ligands, showing a slightly distorted triangular bipyramidal geometry. Furthermore, it exhibits a zero-dimensional network structure with a sixteen-membered ring and shows yellow photoluminescent property at room temperature.
基金supported by NNSFC (20971085)"973" Programs (2007CB209701 and 2009CB930403)the Key Project and Scientific Research Foundation for the Returned Overseas Chinese Scholars of State Education Ministry
文摘Two homochiral mercury (1) and cadmium (2) complexes derived from chiral twisted biphenyl pyridine ligand (3,3'-bipyridine-5,5',6,6'-tetramethyl-2,2'-dimethoxy-1,1'-biphenyl) have been synthesized and characterized by IR, microanalysis, TGA, UV-Vis, powder and single-crystal X-ray crystallography. Both 1 and 2 crystallize in orthorhombic space group P21212 with Z = 2. For 1, a = 14.2038(16), b = 14.3630(17), c = 7.0257(8), V = 1433.3(3)3, Mr = 878.91, Dc = 2.037 g/cm3, μ = 7.549 mm-1, F(000) = 824, the final GOF = 1.017, R = 0.0296 and wR = 0.0645 for 2925 observed reflections with I 2σ(I). For 2, a = 14.212(3), b = 14.392(3), c = 7.0498(14), V = 1442.0(5)3, Mr = 790.72, Dc = 1.821 g/cm3, μ = 2.924 mm–1, F(000) = 760, the final GOF = 1.075, R = 0.0340 and wR = 0.0834 for 3144 observed reflections with I 2σ(I). The crystal structures of 1 and 2 are isostructural and each adopts a two-dimensional supramolecular network which contains the C–H···π interactions.
文摘A new dinuclear copper(II) complex ([Cu(C12H17N2O)(N3)]2, C24H34Cu2N10O2) has been synthesized and characterized by X-ray structure determination. It crystallizes in the monoclinic system, space group P21/c with a = 18.529(4), b = 10.933(2), c = 14.534(3) ?, β = 111.07(3)°, V = 2748(1) ?3, Z = 4, Mr = 621.69, F(000) = 1288, Dc = 1.503 g/cm3 and μ(MoKα) = 1.590 mm?1. The structure was refined to R = 0.0647 and wR = 0.1846 for 4406 observed reflections (I > 2σ(I)). The asymmetric unit comprises two halfmolecules. The complex is a centrosymmetric dimmer in which the copper atoms are penta-coordinated by three coordination atoms from the corresponding tridentate Schiff base ligand and two bridging azide anions. The Cu(II)…Cu(II) average distance is 3.350(1) ?.
文摘A discrete binuclear copper (II) complex containing Cu 2O 2 unit has been synthesized by the reaction of Cu (ClO 4) 2·6H 2O with 2 aminopyridine in the CH 3OH solution and characterized by X ray diffraction study and IR spectroscopy. The crystal is monoclinic, space group: P2 1/n, with unit cell parameters: a=8.2952(2), b=18.4633(3), c=10.5049(2) . β=108.965(1)°, V=1521.56(5) 3, Z=2, C 22 H 30 N 8O 10 Cl 2Cu 2, M r =764.52, D c =1.669 Mg/m 3, F(000)=780, μ (Mo Kα )=8.60, T =293(2)K, final R=0.0623, wR =0.1536 for 2660 observed reflections with I>2.0σ(I ). The centrosymmetric complex Cu 2(CH 3O) 2(C 5H 6N 2) 4(ClO 4) 2 comprises a pair of Cu(II) atoms bridged by two methanoxo and N coordination 2 aminopyridine. The Cu(II)…Cu(II) distance is 3\^002(1).
文摘The title complex Ni(C4H5NO4)(C7H6N2)31.75(H2O) (C25H26.5N7NiO5.75, Mr = 575.74) has been prepared and its crystal structure was determined by X-ray diffraction method. The crystal of this chiral complex belongs to monoclinic, space group P21 with a = 13.208(1), b = 10.741(1), c = 19.398(1) ? b = 104.39(1)o, V = 2665.8(4) 3, Z = 4, Dc = 1.435 g/cm3, m(MoKa) = 0.780 mm-1 and F(000) = 1198. The final R = 0.0504 and wR = 0.1267 for 9159 observed reflections (I > 2s(I)), and R = 0.065 and wR = 0.1299 for 11006 independent reflections. The complex assumes a distorted octa- hedral coordinate geometry formed by one aspartate dianion and three benzimidazole ligands. The aspartate chelates to the Ni atom as a tridentate ligand. The lattice water molecules are hydrogen- bonded to the Ni complex molecule.
基金The project was supported by the Education Department of Zhejiang Province (20030710)
文摘The title complex, C18H15N3NiO3, has been prepared and characterized by X-ray diffraction analysis. It crystallizes in the monoclinic system, space group Cc with a = 10.939(2), b = 22.909(5), c = 6.907(1) ?, β = 116.75(3)°, V = 1545.7(5) ?, Z = 4, Mr = 380.04, F(000) = 784, Dc = 1.633 g/cm3 and μ(MoKα) = 1.279 mm–1. The structure was refined to R = 0.0472 and wR = 0.0893 for 2571 observed reflections with I > 2σ(I). The absolute structure Flack parameter X is 0.01(2). In this crystal structure, strong face-to-face π-π stacking interactions between adjacent molecules lead to a one-dimensional chain structure.
基金This work was supported by the National Natural Science Foundation of China (No. 20101003), Natural Science Foundation of Heilongjiang Province (No. B0007) and the Scientific Fund of Remarkable Teachers of Heilongjiang Province (1054G036)
文摘A novel dinuclear complex with an empirical formula [Co2(1H-benzimidazole)4(1, 4-bdoa)2] (1,4-bdoa2– = benzene-1,4-dioxyacetate dianion) has been synthesized and characterized by elemental analysis, IR and single-crystal X-ray diffraction. It crystallizes in monoclinic system, space group P21/c with a = 11.000(2), b = 19.385(4), c = 11.417(2) ?, β = 95.49(3)o, V = 2423.3(8) ?3, Z = 2, Mr = 1074.77, Dc = 1.473 g/cm3, μ = 0.760 mm–1, F(000) = 1108, the final R = 0.0645 and wR = 0.0714 for 3273 observed reflections (I > 2σ(I)). Two octahedrally coordinated Co(II) atoms are bridged by two 1,4-bdoa2– groups, generating a macrocyclic ring complex. The Co…Co separa- tion is 7.677(3) ?. An extended 3-D supramolecular network is formed through hydrogen bonds and weak π-π stacking interactions.
基金Supported by the Science and Technology Foundation of Ministry of Development of China (2010-K6-8)Science Foundation of Suzhou University of Science and Technology
文摘The cobalt(II) complex with (quinolin-8-yloxy)acetate, [CoCl(C11H8NO3)]n (1), has been prepared via the solvothermal method and characterized by IR, elemental analysis, UV- Vis diffuse-reflection spectra and single-crystal X-ray diffraction analysis. Complex 1 is a novel carboxylate-bridged one-dimensional helical cobalt(II) polymer, and the Co(II) centre exhibits an approximately square pyramidal CoClNO3 coordination geometry. It crystallizes in monoclinic, space group P21/n, with a = 9.1594(10), b = 6.8864(7), c = 17.290(2) , β = 102.629(3)o, C11H8ClCoNO3, Mr = 296.56, V = 1064.2(2) 3, Z = 4, Dc = 1.851 g/cm3, F(000) = 596, μ = 1.856 mm-1, the final R = 0.0308 and wR = 0.0807. Interestingly, the chain complexes are assembled to form two-dimensional networks through intermolecular face-to-face π-π stacking interactions with the centroid-to-centroid distance of 3.559(1) and the dihedral angle of 8.4(1)° between the aromatic rings.
基金supported by the Knowledge Innovation Program(No.KJCX2-EW-H01)of Chinese Academy of SciencesNational Natural Science Foundation of China(No.21003125,21073190)Natural Science Foundation of Fujian Province(2010J05040,2010J01057)
文摘A new copper(II)-2,2'-biimidazole metal-organic POMs-supported compound [Cu(H2biim)2]{[Cu(H2biim)212[H10W12O44]}'8H2O (H2biim = 2,2'-biimidazole) has been success- fully synthesized under hydrothermal conditions and characterized by single-crystal X-ray diffraction, IR spectroscopy, elemental analysis and TG. The crystal adopts space group Pi with a = 11.800(2), b = 13.437(3), c = 13.685(3) A, V = 1922.5(7) A3, D,. = 3.507 g/cm3, C36H62Cu3N24W12O52, M,. = 4059.92, F(000) = 1837,μ = 18.796 mm-1, Z = 1, R = 0.0579 and wR = 0.1465 for 8734 observed reflections (I 〉 2σ(I)). X-ray crystallography analysis exhibits that the title compound consists of one [H10W12044]6- polyanion and three [Cu(H2biim)2] units. And significant π-π stacking interactions and intermolecular O-H-,.O or N-H.'-O hydrogen-bonding interactions lead to a three-dimensional supramolecular framework. Thermal stability and magnetic property of the complex have also been investigated.
基金Supported by the National Natural Science Foundation of China(20576052) the Joint Innovation Fund of Jiangsu Province(BY2009107) the National Basic Research Program of China(2003CB615707)
文摘Three stable 4-substituted pyridine-based ruthenium(II)complexes[RuCl2(PPh3)L](L=4-R-2,6-bis (diethylaminomethylene)pyridine,R=Br,H or allyloxy)were synthesized.The catalytic activities of the complexes toward transfer hydrogenation from alcohols to ketones were investigated.The electronic effects of the para-substituent in the pyridyl ring were probed and we found that the electron-donating group increased the catalytic activity.The result suggests that an electron-donating group is probably preferential for linking the catalytic ruthenium complex and the chemically inert supporting molecules such as a carbosilane dendrimer.