The stability constants of some ternary mixed-ligand complexes, Pt(Phen)(CA)+, where Phen=1,10-phenanthroline and CA- =carboxylate, were determined by means of potentiometric pH titration in aqueous solutions(I=0.1 mo...The stability constants of some ternary mixed-ligand complexes, Pt(Phen)(CA)+, where Phen=1,10-phenanthroline and CA- =carboxylate, were determined by means of potentiometric pH titration in aqueous solutions(I=0.1 mol/L, KNO 3; 25 ℃), and the stability of them was compared with that of the corresponding binary complexes. It was revealed that the ternary complexes containing phenylalkane carboxylates ligands(PCA-) are much more stable than those formed with formate and acetate. The results indicate that there exist the intramolecular aromatic-ring interactions between the phenanthroline ring of Phen and the phenyl moiety of ligand PCA- in the ternary mixed-ligand Pt(Phen)(PCA)- complexes. The extent of the stacking interactions, which depends on the number of methylene groups between the phenyl moieties and the coordinated phenylalkane carboxylate groups, was calculated. The best-fitted stack was obtained for the complexes with 2-phenylacetate and 3-phenylpropionate as the ligands.展开更多
One of the typical phenomena of intramolecular ligand-ligand interaction in complexes is the aromatic-ring stacking which depends on the stacking of those non-coordinating aromatic rings. Since 1974 H. Sigel reported ...One of the typical phenomena of intramolecular ligand-ligand interaction in complexes is the aromatic-ring stacking which depends on the stacking of those non-coordinating aromatic rings. Since 1974 H. Sigel reported that the stacking interaction was observed between pyridine ring of bpy（bpy=2, 2′-bipyridyl） and purine ring of ATP<sup>4-</sup>(ATP<sup>4-</sup>=adenosine 5′-triphosphate) among the mixed-ligand Cu（bpy） （ATP）<sup>2-</sup> complexes. The study on this field has been extended to a large amount of ligands such as nucleotides, xanthosines,展开更多
So far, more attention was paid to the fact that the kind, position and properties of the substituted radicals of coordinating or non-coordinating groups in the complexes exert an important influence on the stability ...So far, more attention was paid to the fact that the kind, position and properties of the substituted radicals of coordinating or non-coordinating groups in the complexes exert an important influence on the stability of the complexes, but less to the interaction between those non-coordinating groups. Although the existence of hydrogen bonds between ligands and the formation of covalent and ionic bonds have been reported, it is only about ten展开更多
The stability constants of the binary ML2+ and ternary M(ATP)L2? complexes, where L=Iq (isoquinoline) or BIm (benzimidazole) and M=Zn2+ or Cd2+, have been determined by potentiometric pH titration in aqueous solution ...The stability constants of the binary ML2+ and ternary M(ATP)L2? complexes, where L=Iq (isoquinoline) or BIm (benzimidazole) and M=Zn2+ or Cd2+, have been determined by potentiometric pH titration in aqueous solution at I=0.1 mol/L (NaClO4), T=25°C. The stability of the ternary complexes characterized by ΔlogKM=logKM(ATP)LM(ATP)L- logKMML corresponding to the equilibrium M(ATP)2? + ML2+ = M(ATP)L2? + M2+ in higher than what would be expected on statistical grounds. The increase may be related to the stacking interaction between the aromatic ring of the ligands L and the purine moiety of ATP4–. 1H NMR studies of Zn2+/ATP4?/L confirm the presence of stacking in the ternary complexes. It is concluded that the strength of the intramolecular stacking interaction ia dependent on the structure of the aromatic ring of the ligand L and the formation of a metal ion bridge. Possible implications an discussed briefly.展开更多
A synergistically directed assembly approach to distinctive metal-organic frameworks utilizing both donor-acceptor (D-A) interaction from aromatic systems and coordination interactions is presented.Based on such an ap...A synergistically directed assembly approach to distinctive metal-organic frameworks utilizing both donor-acceptor (D-A) interaction from aromatic systems and coordination interactions is presented.Based on such an approach,the coronene-tpt (tpt =2,4,6-tri(4-pyridyl)-1,3,5-triazine) stacks based coronene-MOF-1-4 have been successfully fabricated.Their structural discrepancies with coroneneabsent control products,1'-4',illustrate clearly the significance of coronene-tpt based D-A interactions in these architectures.All these coronene-MOFs contain varied coronene-tpt stacks as organic secondary building blocks (SBUs),which are closely interrelated with the coordination based framework structures.Moreover,porous coronene-MOF-1 and-2 exhibit high physicochemical stability and significant light hydrocarbons storage and separation performances.展开更多
CONSPECTUS:Controlling self-assembled peptide nanostructures has emerged as a significant area of research,offering versatile tools for developing functional materials for various applications.This Account emphasizes ...CONSPECTUS:Controlling self-assembled peptide nanostructures has emerged as a significant area of research,offering versatile tools for developing functional materials for various applications.This Account emphasizes the essential role of noncovalent interactions,particularly in peptide-based materials.Key forces,such as aromatic stacking and hydrogen bonding,are crucial for promoting molecular aggregation and stabilizing supramolecular structures.Numerous studies demonstrate how these interactions influence the phase transitions and the morphology of self-assembled structures.Recent advances in computational methodologies,including molecular dynamics simulations and machine learning,have significantly enhanced our understanding of self-assembly processes.These tools enable researchers to predict how molecular properties,such as hydrophobicity,charge distribution,and aromaticity,affect assembly behavior.Simulations uncover the energetic landscapes governing peptide aggregation,providing insights into the kinetic pathways and thermodynamic stabilities.Meanwhile,machine learning facilitates the rapid screening of peptide libraries,identifying sequences with optimal self-assembly characteristics,and accelerating material design with tailored functionalities.Beyond their structural and physicochemical properties,self-assembled peptide nanostructures hold immense potential in biological applications due to their versatility and biocompatibility.By manipulating molecular interactions,researchers have engineered responsive systems that interact with cellular environments to elicit specific biological responses.These peptide nanostructures can mimic extracellular matrices,facilitating cell adhesion,proliferation,and differentiation.They also show promise in modulating immune responses,recruiting immune cells,and regulating signaling pathways,making them valuable tools in immunotherapy and regenerative medicine.Moreover,their ability to disrupt bacterial membranes positions them as innovative alternatives to conventional antibiotics,addressing the urgent need for solutions to antimicrobial resistance.Despite its promise,peptide self-assembly faces several challenges.The assembly process is highly sensitive to environmental conditions,such as pH,temperature,and ionic strength,leading to variability in the morphology and properties.Furthermore,peptide aggregation can result in heterogeneous and poorly defined assemblies,complicating the reproducibility and scalability.Designing peptides with predictable self-assembly behavior remains a significant hurdle.Looking ahead,integrating computational predictions with experimental validations will be crucial in discovering novel peptide sequences with tailored self-assembly properties.Machine learning,combined with high-throughput screening techniques,will enable the rapid identification of optimal peptide sequences.In situ characterization tools,such as cryoelectron microscopy and advanced spectroscopy,will provide deeper insights into assembly mechanisms,aiding the rational design of peptide materials.As research progresses,the dynamic and reversible nature of noncovalent interactions can be leveraged to create adaptive responsive to environmental stimuli.Self-assembled peptide nanostructures are poised for impactful applications in biomedicine including targeted drug delivery,tissue repair,and advanced therapeutic strategies.Ultimately,these nanostructures represent a powerful platform for addressing complex challenges in biomedicine and beyond,paving the way for transformative breakthroughs in science and technology.展开更多
A series of novel molecules with a cyclen(1,4,7,10-tetraazacyclododecane)moiety appended on and bearing different aromatic fragments in the structures were synthesized and characterized.The binding activities of these...A series of novel molecules with a cyclen(1,4,7,10-tetraazacyclododecane)moiety appended on and bearing different aromatic fragments in the structures were synthesized and characterized.The binding activities of these compounds towards DNA were systematically studied by spectroscopic,viscometric and gel electrophoresis methods.The results suggest that the stacking interaction plays an important role in improving the DNA binding ability of the compounds.The binding modes of the compounds towards DNA are also affected by the sizes of the aromatic rings.The binding interaction between binaphthyl compound 1b and several nucleosides was studied by fluorescence titration.Stacking interaction and hydrophobic interaction play the key role in such non-selective binding process.展开更多
Four new coordination polymers,{[Cd(mbtx)(4OHphCOO)]NO_(3)}n(1),{[Zn(mbtx)(1,4-bdc)_(0.5)(H_(2)O)_(2)]·(1,4-bdc)_(0.5)·4H_(2)O}n(2),{[Cd2(mbtx)(5NO_(2)-bdc)_(2)(H_(2)O)_(3)]·4.5H_(2)O}n(3),and{[Zn(H_(2)...Four new coordination polymers,{[Cd(mbtx)(4OHphCOO)]NO_(3)}n(1),{[Zn(mbtx)(1,4-bdc)_(0.5)(H_(2)O)_(2)]·(1,4-bdc)_(0.5)·4H_(2)O}n(2),{[Cd2(mbtx)(5NO_(2)-bdc)_(2)(H_(2)O)_(3)]·4.5H_(2)O}n(3),and{[Zn(H_(2)O)6][Zn_(2)(mbtx)_(2)(btc)_(2)(H_(2)O)_(4)]·2H_(2)O}n(4)(mbtx=1,3-bis(4H-1,2,4-triazole)benzene,4OHphCOO-=p-hydroxybenzoate,1,4-bdc2-=1,4-benzenedicarboxylate,5NO_(2)-bdc2-=5-nitro-isophthalate,btc3-=1,3,5-benzenetricarboxylate),were synthesized under room temperature condition and characterized by single-crystal X-ray diffraction,elemental analyses,and powder X-ray diffraction.Single-crystal X-ray structural analysis shows that complexes 1 and 3 are 2D networks.In 1,the adjacent 2D networks are linked to a 3D network byπ-πstacking interaction.2 and 4 exhibit 1D chains,and the 1D chains are connected into a 3D network byπ-πstacking interaction and intermolecular hydrogen bond.Luminescence and thermogravimetric analysis of the four complexes were discussed.CCDC:2416406,1;2416407,2;2416408,3;2416409,4.展开更多
π-πstacking,a fundamental noncovalent interaction between aromatic molecules,is essential for enabling charge transport across molecular fragments a process vital to both chemistry and biology.^(1,2)Owing to the wid...π-πstacking,a fundamental noncovalent interaction between aromatic molecules,is essential for enabling charge transport across molecular fragments a process vital to both chemistry and biology.^(1,2)Owing to the widespread importance ofπ-πinteractions in diverse fields,there is considerable interest in precisely modulating the interaction at the single-molecule scale.Studies have shown thatπ-πinteraction can be influenced by adjusting molecular concentration,^(3) applying mechanical forces,^(4) or designing target molecules with enhanced attraction.^(5)However,achieving precise control of intermolecularπ-πinteraction at the single-molecule level without altering molecular conformation or concentration remains a significant challenge.展开更多
A new binuclear copper(Ⅱ) complex, [Cu2(phen)2(H2O)2( μ2-C2O4)](NO3)2, has been synthesized and characterized by elemental analysis, IR and UV-Vis spectrum. Its crystal structure was determined by single crystal X-r...A new binuclear copper(Ⅱ) complex, [Cu2(phen)2(H2O)2( μ2-C2O4)](NO3)2, has been synthesized and characterized by elemental analysis, IR and UV-Vis spectrum. Its crystal structure was determined by single crystal X-ray diffraction techniques. Crystal data: monoclinic, space group P21/c, a=0.712 21(8) nm, b=1.170 93(14) nm, c=1.783 7(2) nm, β=111.828(2)°, and V=1.380 8(3) nm3, Dc=1.769 Mg·m-3, Z=2, F(000)=744, R1=0.025 4, wR2=0.069 5, Gof=1.077, Δρ=328^-455 e·nm-3. The complex is packed by one centrosymmetry binuclear copper(Ⅱ) unit, oxalate dianion and NO3- anion. In the molecule structure of the title complex, two Cu(Ⅱ) ions are bridged by oxalate dianion and each Cu(Ⅱ) ions coordinates with two nitrogen atoms from 1,10-phenanthroline ligand and one oxygen atom from water to form a five-coordinate distorted square-pyramidal configuration. The hydrogen bonds are observed between coordinated water molecules and NO3- anions. The analysis of the crystal structure indicates that the complex has a two-dimensional stacking network structure, which is formed by intramolecular hydrogen bonds, intermolecular hydrogen bonds and stacking effect of aromatic ring. CCDC: 255345.展开更多
The title complex, [Cu(Hsal)2(py)2], was synthesized by layered solution technique and structurally characterized by single crystal X ray. The copper atom has a square pyramidal geometry and the coordination number is...The title complex, [Cu(Hsal)2(py)2], was synthesized by layered solution technique and structurally characterized by single crystal X ray. The copper atom has a square pyramidal geometry and the coordination number is five. The molecular structure is linear one dimensional network. There is a stacking effect between pyridine ligands of neighbouring 1 D chains and the molecular structure is extended into two dimensional stacking network. Two salicylates in the complex have a position of crab pincers like, in which one salicylate is unidentate and another coordinates through the carboxylate group and phenyl group unidentately.展开更多
基金Supported by the Foundation of Academ y L eader of Zhejiang Gongshang U niversity(No.19972 0 0 2 )
文摘The stability constants of some ternary mixed-ligand complexes, Pt(Phen)(CA)+, where Phen=1,10-phenanthroline and CA- =carboxylate, were determined by means of potentiometric pH titration in aqueous solutions(I=0.1 mol/L, KNO 3; 25 ℃), and the stability of them was compared with that of the corresponding binary complexes. It was revealed that the ternary complexes containing phenylalkane carboxylates ligands(PCA-) are much more stable than those formed with formate and acetate. The results indicate that there exist the intramolecular aromatic-ring interactions between the phenanthroline ring of Phen and the phenyl moiety of ligand PCA- in the ternary mixed-ligand Pt(Phen)(PCA)- complexes. The extent of the stacking interactions, which depends on the number of methylene groups between the phenyl moieties and the coordinated phenylalkane carboxylate groups, was calculated. The best-fitted stack was obtained for the complexes with 2-phenylacetate and 3-phenylpropionate as the ligands.
基金Project supported by the National Natural Science Foundation of China
文摘One of the typical phenomena of intramolecular ligand-ligand interaction in complexes is the aromatic-ring stacking which depends on the stacking of those non-coordinating aromatic rings. Since 1974 H. Sigel reported that the stacking interaction was observed between pyridine ring of bpy（bpy=2, 2′-bipyridyl） and purine ring of ATP<sup>4-</sup>(ATP<sup>4-</sup>=adenosine 5′-triphosphate) among the mixed-ligand Cu（bpy） （ATP）<sup>2-</sup> complexes. The study on this field has been extended to a large amount of ligands such as nucleotides, xanthosines,
基金Project supported by the National Natural Science Foundation of China.
文摘So far, more attention was paid to the fact that the kind, position and properties of the substituted radicals of coordinating or non-coordinating groups in the complexes exert an important influence on the stability of the complexes, but less to the interaction between those non-coordinating groups. Although the existence of hydrogen bonds between ligands and the formation of covalent and ionic bonds have been reported, it is only about ten
基金Project (No.29170038) supported by the National Natural Science Foundation of China。
文摘The stability constants of the binary ML2+ and ternary M(ATP)L2? complexes, where L=Iq (isoquinoline) or BIm (benzimidazole) and M=Zn2+ or Cd2+, have been determined by potentiometric pH titration in aqueous solution at I=0.1 mol/L (NaClO4), T=25°C. The stability of the ternary complexes characterized by ΔlogKM=logKM(ATP)LM(ATP)L- logKMML corresponding to the equilibrium M(ATP)2? + ML2+ = M(ATP)L2? + M2+ in higher than what would be expected on statistical grounds. The increase may be related to the stacking interaction between the aromatic ring of the ligands L and the purine moiety of ATP4–. 1H NMR studies of Zn2+/ATP4?/L confirm the presence of stacking in the ternary complexes. It is concluded that the strength of the intramolecular stacking interaction ia dependent on the structure of the aromatic ring of the ligand L and the formation of a metal ion bridge. Possible implications an discussed briefly.
基金This work was supported by the National Natural Science Foundation of China (Nos. 21421001, 21531005, 91856124, and 21875115)the Programme of Introducing Talents of Discipline to Universities (B18030)the General Financial Grant from the China Postdoctoral Science Foundation (No. 2017M621056).
文摘A synergistically directed assembly approach to distinctive metal-organic frameworks utilizing both donor-acceptor (D-A) interaction from aromatic systems and coordination interactions is presented.Based on such an approach,the coronene-tpt (tpt =2,4,6-tri(4-pyridyl)-1,3,5-triazine) stacks based coronene-MOF-1-4 have been successfully fabricated.Their structural discrepancies with coroneneabsent control products,1'-4',illustrate clearly the significance of coronene-tpt based D-A interactions in these architectures.All these coronene-MOFs contain varied coronene-tpt stacks as organic secondary building blocks (SBUs),which are closely interrelated with the coordination based framework structures.Moreover,porous coronene-MOF-1 and-2 exhibit high physicochemical stability and significant light hydrocarbons storage and separation performances.
基金supported by the National Natural Science Foundation of China(82272145)and the Foundation of Westlake University.
文摘CONSPECTUS:Controlling self-assembled peptide nanostructures has emerged as a significant area of research,offering versatile tools for developing functional materials for various applications.This Account emphasizes the essential role of noncovalent interactions,particularly in peptide-based materials.Key forces,such as aromatic stacking and hydrogen bonding,are crucial for promoting molecular aggregation and stabilizing supramolecular structures.Numerous studies demonstrate how these interactions influence the phase transitions and the morphology of self-assembled structures.Recent advances in computational methodologies,including molecular dynamics simulations and machine learning,have significantly enhanced our understanding of self-assembly processes.These tools enable researchers to predict how molecular properties,such as hydrophobicity,charge distribution,and aromaticity,affect assembly behavior.Simulations uncover the energetic landscapes governing peptide aggregation,providing insights into the kinetic pathways and thermodynamic stabilities.Meanwhile,machine learning facilitates the rapid screening of peptide libraries,identifying sequences with optimal self-assembly characteristics,and accelerating material design with tailored functionalities.Beyond their structural and physicochemical properties,self-assembled peptide nanostructures hold immense potential in biological applications due to their versatility and biocompatibility.By manipulating molecular interactions,researchers have engineered responsive systems that interact with cellular environments to elicit specific biological responses.These peptide nanostructures can mimic extracellular matrices,facilitating cell adhesion,proliferation,and differentiation.They also show promise in modulating immune responses,recruiting immune cells,and regulating signaling pathways,making them valuable tools in immunotherapy and regenerative medicine.Moreover,their ability to disrupt bacterial membranes positions them as innovative alternatives to conventional antibiotics,addressing the urgent need for solutions to antimicrobial resistance.Despite its promise,peptide self-assembly faces several challenges.The assembly process is highly sensitive to environmental conditions,such as pH,temperature,and ionic strength,leading to variability in the morphology and properties.Furthermore,peptide aggregation can result in heterogeneous and poorly defined assemblies,complicating the reproducibility and scalability.Designing peptides with predictable self-assembly behavior remains a significant hurdle.Looking ahead,integrating computational predictions with experimental validations will be crucial in discovering novel peptide sequences with tailored self-assembly properties.Machine learning,combined with high-throughput screening techniques,will enable the rapid identification of optimal peptide sequences.In situ characterization tools,such as cryoelectron microscopy and advanced spectroscopy,will provide deeper insights into assembly mechanisms,aiding the rational design of peptide materials.As research progresses,the dynamic and reversible nature of noncovalent interactions can be leveraged to create adaptive responsive to environmental stimuli.Self-assembled peptide nanostructures are poised for impactful applications in biomedicine including targeted drug delivery,tissue repair,and advanced therapeutic strategies.Ultimately,these nanostructures represent a powerful platform for addressing complex challenges in biomedicine and beyond,paving the way for transformative breakthroughs in science and technology.
基金supported by the National Natural Science Foundation of China(Grant Nos.20725206 and 20732004)Specialized Research Fund for the Doctoral Program of Higher EducationScientific Fund of Sichuan Province for Outstanding Young Scientists
文摘A series of novel molecules with a cyclen(1,4,7,10-tetraazacyclododecane)moiety appended on and bearing different aromatic fragments in the structures were synthesized and characterized.The binding activities of these compounds towards DNA were systematically studied by spectroscopic,viscometric and gel electrophoresis methods.The results suggest that the stacking interaction plays an important role in improving the DNA binding ability of the compounds.The binding modes of the compounds towards DNA are also affected by the sizes of the aromatic rings.The binding interaction between binaphthyl compound 1b and several nucleosides was studied by fluorescence titration.Stacking interaction and hydrophobic interaction play the key role in such non-selective binding process.
文摘Four new coordination polymers,{[Cd(mbtx)(4OHphCOO)]NO_(3)}n(1),{[Zn(mbtx)(1,4-bdc)_(0.5)(H_(2)O)_(2)]·(1,4-bdc)_(0.5)·4H_(2)O}n(2),{[Cd2(mbtx)(5NO_(2)-bdc)_(2)(H_(2)O)_(3)]·4.5H_(2)O}n(3),and{[Zn(H_(2)O)6][Zn_(2)(mbtx)_(2)(btc)_(2)(H_(2)O)_(4)]·2H_(2)O}n(4)(mbtx=1,3-bis(4H-1,2,4-triazole)benzene,4OHphCOO-=p-hydroxybenzoate,1,4-bdc2-=1,4-benzenedicarboxylate,5NO_(2)-bdc2-=5-nitro-isophthalate,btc3-=1,3,5-benzenetricarboxylate),were synthesized under room temperature condition and characterized by single-crystal X-ray diffraction,elemental analyses,and powder X-ray diffraction.Single-crystal X-ray structural analysis shows that complexes 1 and 3 are 2D networks.In 1,the adjacent 2D networks are linked to a 3D network byπ-πstacking interaction.2 and 4 exhibit 1D chains,and the 1D chains are connected into a 3D network byπ-πstacking interaction and intermolecular hydrogen bond.Luminescence and thermogravimetric analysis of the four complexes were discussed.CCDC:2416406,1;2416407,2;2416408,3;2416409,4.
文摘π-πstacking,a fundamental noncovalent interaction between aromatic molecules,is essential for enabling charge transport across molecular fragments a process vital to both chemistry and biology.^(1,2)Owing to the widespread importance ofπ-πinteractions in diverse fields,there is considerable interest in precisely modulating the interaction at the single-molecule scale.Studies have shown thatπ-πinteraction can be influenced by adjusting molecular concentration,^(3) applying mechanical forces,^(4) or designing target molecules with enhanced attraction.^(5)However,achieving precise control of intermolecularπ-πinteraction at the single-molecule level without altering molecular conformation or concentration remains a significant challenge.
文摘A new binuclear copper(Ⅱ) complex, [Cu2(phen)2(H2O)2( μ2-C2O4)](NO3)2, has been synthesized and characterized by elemental analysis, IR and UV-Vis spectrum. Its crystal structure was determined by single crystal X-ray diffraction techniques. Crystal data: monoclinic, space group P21/c, a=0.712 21(8) nm, b=1.170 93(14) nm, c=1.783 7(2) nm, β=111.828(2)°, and V=1.380 8(3) nm3, Dc=1.769 Mg·m-3, Z=2, F(000)=744, R1=0.025 4, wR2=0.069 5, Gof=1.077, Δρ=328^-455 e·nm-3. The complex is packed by one centrosymmetry binuclear copper(Ⅱ) unit, oxalate dianion and NO3- anion. In the molecule structure of the title complex, two Cu(Ⅱ) ions are bridged by oxalate dianion and each Cu(Ⅱ) ions coordinates with two nitrogen atoms from 1,10-phenanthroline ligand and one oxygen atom from water to form a five-coordinate distorted square-pyramidal configuration. The hydrogen bonds are observed between coordinated water molecules and NO3- anions. The analysis of the crystal structure indicates that the complex has a two-dimensional stacking network structure, which is formed by intramolecular hydrogen bonds, intermolecular hydrogen bonds and stacking effect of aromatic ring. CCDC: 255345.
文摘The title complex, [Cu(Hsal)2(py)2], was synthesized by layered solution technique and structurally characterized by single crystal X ray. The copper atom has a square pyramidal geometry and the coordination number is five. The molecular structure is linear one dimensional network. There is a stacking effect between pyridine ligands of neighbouring 1 D chains and the molecular structure is extended into two dimensional stacking network. Two salicylates in the complex have a position of crab pincers like, in which one salicylate is unidentate and another coordinates through the carboxylate group and phenyl group unidentately.
