Syntheses,crystal structures,and photophysical properties of two 2-D coordination polymers with different geometries of lead(II)

Two complexes constructed from aromatic acid and N-heterocyclic ligands have been synthesized by hydrothermal reaction: [Pb(cipt)(NDC)]_n (1) [cipt?=?2-(3-chlorophenyl)-1H-imidazo[4,5-f][1,10]phenanthroline, NDC?=?naphthalene-1,4-dicarboxylic acid] and [Pb(ipm)(BDC)₂]_n (2) [BDC?=?terephthalic acid, ipm?=?5-(1H-imidazo[4,5-f][1,10]phenanthrolin-2-yl)-2-methoxyphenol]. Single-crystal X-ray analysis shows that 1 exhibits an interesting arm-shaped chain structure. 1-D ladder chain structure is formed by N–H···O bonding interactions and further into a 2-D network by N–H···O hydrogen bonds and interchain π–π stacking interactions. Complex 2 shows a 2-D butterfly wings structure, which has been rarely reported. The structure in 2 has intermolecular N–H···O interactions, which help in construction of the 3-D framework. In 1, the coordination sphere of Pb(II) is hemi-directed, whereas the Pb(II) geometry in 2 is holo-directed. The solid-state fluorescence spectra of 1 and 2 are also investigated, as well as the ligands cipt and ipm.     

Syntheses,crystal structures,and photophysical properties of two 2-D coordination polymers

Two coordination polymers, [Mn(dipt)(m-BDC)₃] _n (1) and [Pb(mip)(1,4-NDC)] _n (2) [dipt?=?2-(2,4-dichlorophenyl)-1H-imidazo[4,5-f][1,10]phenanthroline, mip?=?2-(3-methoxyphenyl)-1H-imidazo[4,5-f][1,10]phenanthroline, m-BDC?=?isophthalic acid, 1,4-NDC?=?naphthalene-1,4-dicarboxylic acid], have been synthesized by hydrothermal reactions and characterized by elemental analysis, thermogravimetric analysis, infrared spectrum, and single-crystal X-ray diffraction. Single-crystal X-ray diffraction reveals that 1 and 2 have 1-D chain architecture. Complex 1 has a 2-D-layered structure constructed from C–H···O hydrogen bonds. Complex 2 has a 2-D-layered structure constructed from N–H···O hydrogen bonds and π–π interactions. TG analyses suggest 1 and 2 have excellent thermal stabilities from hydrogen bonds and π–π interactions. Mn(II) in 1 has trigonal bipyramidal geometry surrounded by three carboxylate oxygen atoms from three monodentate bridging m-BDC and two nitrogen atoms from one dipt. Pb(II) has [:PbN2O4] pentagonal bipyramidal geometry in 2. The luminescent properties for dipt, mip, 1, and 2 are also presented.     

Ruthenium(II) complexes: synthesis,cytotoxicity in vitro,apoptosis, DNA-binding,photocleavage, and antioxidant activity studies

Two new ruthenium(II) complexes, [Ru(dmp)₂(APIP)](ClO₄)₂ (1) (APIP?=?2-(2-aminophenylimidazo[4,5-f][1,10]phenanthroline), dmp?=?2,9-dimethyl-1,10-phenanthroline) and [Ru(dmp)₂(HAPIP)](ClO₄)₂ (2) (HAPIP?=?2-(2-hydroxyl-5-aminophenyl)imidazo[4,5-f][1,10]phenanthroline), were synthesized and characterized. The DNA-binding properties of these complexes were investigated by absorption titration, viscosity measurements, and photoactivated cleavage. The DNA-binding constants for 1 and 2 have been determined to be 2.3 (±?0.3)?×?10⁴ (mol?L^?1)^?1 and 3.3 (±?0.4)?×?10⁴ (mol?L^?1)^?1. The results indicate that 1 and 2 interact with DNA through intercalative mode. The cytotoxicities of 1 and 2 were assessed against BEL-7402, HepG-2 and MCF-7 cell lines using standard MTT assay. The apoptosis induced by these complexes was studied with the acridine orange/ethidium bromide staining method. The antioxidant activity on hydroxyl radical was also investigated.     

Synthesis and characterization of Pb(II) compounds constructed from N-tosyl-L-glutamic acid

{[Pb(tsgluo)]?·?H₂O} _n (1), [Pb₂(tsgluo)₂(phen)₂] (2), and [Pb₂(tsgluo)₂(bipy)₂] (3) (H₂tsgluo?=?N-p-tolylsulfonyl-L-glutamate, phen?=?1,10-phenanthroline, bipy?=?2,2′-pyridine) have been synthesized in the absence or presence of phen or 2,2′-bipy and structurally characterized by elemental analysis, IR, and X-ray crystallography. Single-crystal X-ray analyses reveal that tsgluo exhibits two coordination modes to link lead ions. Complex 1 gives a 2-D layer structure while 2 and 3 exhibit monomolecular structures; 3 is further connected into a double-chain structure by hydrogen bonds. Phen and 2,2′-bipy are very important for the crystal structure. Fluorescence of the compounds is also discussed.     

Bimetallic bis(diphenylphosphino)acetylene bridged copper(I) complexes with 1,10-phenanthroline derivatives: synthesis,crystal structure,and spectroscopic characterization

A new series of bimetallic bis(diphenylphosphino)acetylene-bridged copper(I) 1,10-phenanthroline complexes, [Cu₂(dppa)₂(L)₂](BF₄)₂; L?=?1,10-phenanthroline (1); 4-methyl-1,10-phenanthroline (2); 4,7-dimethyl-1,10-phenanthroline (3); and 2,9-dimethyl-1,10-phenanthroline (4), have been prepared and characterized by spectroscopic methods. The X-ray structures of 1 and 4 were determined. The structures consist of centrosymmetric bimetallic 10-membered chair-like dimetallacycles. In 1, intermolecular C–H?π interactions result in bending of the phenanthroline ligand and sterically induced lengthening of one Cu–P bond. In 1–4, the ³¹P NMR downfield coordination shift, relative to the free ligand, correlates with the basic strength of the 1,10-phenanthroline ligands.     

Hydrothermal synthesis,structure, and properties of lead(II)-based coordination compounds with R-isophthalic acid (R=OH,CH3)

Three new lead(II)-based coordination polymers, [Pb(5-OH-BDC)] _n ?·?nH₂O (1) (5-OH-BDC?=?5-hydroxyisophthalate), [Pb₂(5-CH₃-BDC)₂] _n (2), and [Pb₂(5-CH₃-BDC)₂(phen)₂] _n ?·?2nH₂O (3) (5-CH₃-BDC?=?5-methylisophthalate, phen?=?1,10-phenanthroline), have been hydrothermally synthesized, structurally determined by single-crystal X-ray diffraction, and characterized by elemental analyses, IR spectra, and thermogravimetric analyses. Both 1 and 2 exhibit 2-D double-layer network structures, while 3 possesses 1-D chain structure bridged by 5-CH₃-BDC. The coordination sphere of Pb(II) in 1 is holodirected, whereas in 2 and 3 the spheres feature hemidirected structures. Fluorescence properties of 1–3 have been investigated in the crystalline state at room temperature.     

Synthesis and crystal structures of two lead(II) complexes of 4,4,4-trifluoro-1-naphthyl-1,3-butanedione ligand,subtle interplay of weak intermolecular interactions

[Pb₂(tfnb)₄ (µ-CH₃OH)] _n (1) and [Pb₂(dmp)₂(tfnb)₄] (2) (tfnb and dmp are the abbreviations for 4,4,4-trifluoro-1-naphthyl-1,3-butanedionate and 2,9-dimethyl-1,10-phenanthroline) have been synthesized and characterized by elemental analysis, IR, ¹H NMR spectroscopy, and thermal analysis. The single-crystal structure of 1 shows that the complex forms two 1-D polymeric networks containing four types of Pb²⁺ with coordination numbers seven for Pb(1) and Pb(3), five for Pb(2), and six for Pb(4). The single-crystal structure of 2 shows that the complex forms a dinuclear complex with eight-coordinate Pb(II). The supramolecular features in this complex are guided by lone-pair activity and the control of weak directional intermolecular interactions and aromatic π–π stacking interactions.     

Synthesis,characterization, and antitumor properties of ruthenium(II) anthraquinone complexes

Three new Ru(II) complexes, [Ru(dmb)₂(ipad)](ClO₄)₂ (dmb = 4,4′-dimethyl-2,2′-bipyridine, ipad = 2-(anthracene-9,10-dione-2-yl) imidazo[4,5-f][1,10]phenanthroline, 1), [Ru(dmp)₂(ipad)](ClO₄)₂ (dmp = 2,9-dimethyl-1,10-phenanthroline, 2), and [Ru(dip)₂(ipad)](ClO₄)₂ (dip = 4,7-diphenyl-1,10-phenanthroline, 3), have been synthesized and characterized. The three Ru(II) complexes intercalate with the base pairs of DNA. The in vitro antiproliferative activities and apoptosis-inducing characteristics of these complexes were investigated. The complexes exhibited cytotoxicity against various human cancer cell lines. BEL-7402 cells displayed the highest sensitivity to 1, accounted for by the greatest cellular uptake. Complex 1 was shown to accumulate preferentially in the nuclei of BEL-7402 cells and cause DNA damage and induce apoptosis, which involved cell cycle arrest and reactive oxygen species generation.     

Two manganese(II) complexes constructed from 2-(3-pyridyl)-imidazo[4,5-f] 1,10-phenanthroline and organic dicarboxylates: syntheses,crystal structures,and luminescence

In this study, two new Mn(II) complexes consisting of a phenanthroline derivative and organic acid ligands, [Mn(3-PIP)(1,3-bdc)] _n (1) and [Mn(3-PIP)₂(1,4-bdc)] _n (2) (3-PIP?=?2-(3-pyridyl)-imidazo[4,5-f]?1,10-phenanthroline, 1,3-H₂bdc?=?benzene-1,3-dicarboxylic acid, 1,4-H₂bdc?=?benzene-1,4-dicarboxylic acid), have been synthesized via hydrothermal reaction and characterized by Fourier transform infrared (FT-IR) spectra, elemental analyses, and single-crystal X-ray diffraction. Complex 1 is a one-dimensional (1-D) twisted double chain bridged by 1,3-bdc. The 3-PIP ligands in a parallel fashion are alternately attached to both sides of the 1-D double chain. Complex 2 exhibits a 1-D zigzag chain, to which pairs of crossed 3-PIP ligands are alternately attached. The two complexes are further extended into three-dimensional (3-D) supramolecular structures by hydrogen-bonding and π–π stacking interactions. The N-donor ligands with an extended π-system play a crucial role in formation and stabilization of the final supramolecular frameworks. Thermal properties of 1 and 2 and fluorescence of 2 are investigated in the solid state.     

Synthesis,characterization, and DNA-binding of [Co(phen)2(CPIA)]3+, [Co(phen)2(BIP)]3+, and [Co(phen)2(CIP)]3+

Three ligands, 2-(3-(carboxymethyl)-1,10-phenanthroline-[5,6-d]imidazole-1-yl)acetate (CPIA), 2-(benzo[d][1,3]dioxol-4-yl)-1H-imidazo[4,5-f][1,10]phenanthroline (BIP), and 2-(9H-carbazol-3-yl)-1H-imidazo[4,5-f][1,10]phenanthroline (CIP), and their complexes, [Co(phen)₂(CPIA)]³⁺ (1) (phen = 1,10-phenanthroline), [Co(phen)₂(BIP)]³⁺ (2), and [Co(phen)₂(CIP)]³⁺ (3), have been synthesized and characterized. Binding of the three complexes with calf thymus DNA (CT-DNA) has been investigated by spectroscopic methods, cyclic voltammetry, and viscosity measurements. The three complexes bind to DNA through an intercalative mode, and the size and shape of the intercalative ligands have significant effects on the binding affinity of complexes to CT-DNA.     

Synthesis,structures, and properties of lead(II) and cobalt(II) metal-organic frameworks based on a flexible benzophenone-2,4′-dicarboxylic acid (H2bpdc)

Two new coordination polymers, [Pb(bpdc)] _n (1) and [Co(bpdc)(phen)] _n (2) [H₂bpdc?=?benzophenone-2,4′-dicarboxylic acid, phen?=?1,10-phenanthroline], have been synthesized and structurally characterized. Hydrogen bonding and π?···?π stacking extend 1 and 2 into 3-D supramolecular architectures, where 1 exhibits a 3-D framework with 1-D hairpin-like helicates based on Pb–O covalent bonds and 2 displays a 3-D network with 1-D zipper-like chains based on Co–O and Co–N covalent bonds. The FT-IR spectra, PXRD and TG analyses are discussed for 1 and 2. Fluorescence spectra and luminescent lifetime are studied for 1.     

Syntheses,structures and luminescence of two copper(I)–dppm complexes,dppm = bis(diphenylphosphino) methane

Two copper(I)–dppm complexes, [Cu₂(dppm)₂(NMP)₂](ClO₄)₂ (1) (NMP?=?2-(4-dimethylaminophenyl)imidazo(4,5-f)(1,10)phenanthroline, dppm?=?bis(diphenylphosphino) methane) and [Cu₂(dppm)₂(phen-NO₂)₂](ClO₄)₂ (2) (phen-NO₂?=?5-nitro-1,10-phenanthroline), were synthesized and their crystal structures were determined by X-ray diffraction. The different ligands chelated to copper(I) give distinct luminescent properties. Complex 1 shows a broad emission (λ _max?=?523?nm) in the visible region with short lifetime (0.33?ns), while complex 2 has a large red shift (λ _max?=?634?nm) and has longer emission lifetime (0.23?µs) compared with complex 1. DFT calculations indicate that emission of 1 and 2 originate from singlet ILCT excited states and triplet MLCT excited states, respectively.     

Crystal engineering of Cd(II) metal–organic frameworks bridged by dicarboxylates and N-donor coligands

Two new metal–organic coordination polymers, {[Cd₄(bpea)₄(IP)₈]?·?6H₂O} _n (1) and {[Cd_1.5(suc)_1.5(IP)_1.5]?·?4H₂O} _n (2) (bpea?=?biphenylethene-4,4′-dicarboxylate, H₂suc?=?succinic acid and IP?=?1H-imidazo[4,5-f][1,10]-phenanthroline), have been obtained through two types of dicarboxylate linkers. Complex 1 contains a neutral 2-D puckered sheet that is interdigitated by neutral 1-D zigzag chains. Compound 2 shows a 2-D (4,4) net, which is extended into a 3-D supramolecular framework by weak aromatic interactions. The different structures demonstrate the effect of the dicarboxylate ligands on the formation of such coordination architectures. The fluorescence property of the two complexes was also investigated.     

Synthesis,characterization, photocleavage,antimicrobial activity and DNA binding of [Co(bpy)2MHPIP]3+, [Co(dmb)2MHPIP]3+, and [Co(phen)2MHPIP]3+ complexes

4-Methyl-2-(2-hydroxyphenyl)imidazo[4,5-f][1,10]phenanthroline) (MHPIP) and its complexes [Co(bpy)₂MHPIP]³⁺ (1) (bpy = 2,2′-bipyridine), [Co(dmb)₂MHPIP]³⁺ (2) (dmb = 4,4′-dimethyl-2,2′-bipyridine), and [Co(phen)₂MHPIP]³⁺ (3) (phen = 1,10-phenanthroline) have been synthesized and characterized by UV/VIS, IR, EA, ¹H, ¹³C-NMR, and mass spectra. The binding of the three complexes with calf-thymus-DNA (CT-DNA) has been investigated by absorption and emission spectroscopy, DNA-melting techniques, viscosity measurements, and DNA cleavage assay. The spectroscopic data and viscosity results indicate that these complexes bind to CT-DNA via an intercalative mode. The complexes also promote photocleavage of plasmid pBR322 DNA and were screened for antimicrobial activity.     

Positional isomeric and N-donor auxiliary chelating ligand effect on engineering crystalline architectures of four lead(II) complexes with diverse fluorescent properties

This work presents an investigation on the positions of the substituent and N-donor auxiliary chelating ligand (bipy/phen) effect on engineering of crystalline architectures of four Pb(II) complexes with a pair of methyl-substituted 3-sulfobenzoic isomers: [Pb(4-msba)(phen)(H₂O)] (1), [Pb(4-msba)(bipy)(H₂O)]·H₂O (2), [Pb(5-msba)(phen)₂]·9H₂O (3), and [Pb₂(5-msba)₂(bipy)₂(H₂O)₂] (4) (4/5-msba?=?4/5-methyl-3-sulfobenzoate, phen?=?1,10-phenanthroline and bipy?=?2,2′-bipyridine). The lead(II) ions exhibit hemidirected geometry in 1–4. The positions of the methyl as well as the auxiliary chelating ligands influence coordination modes of the sulfonates and thus determine the architectures. As the position of methyl in aromatic ring changes from 4 to 5, the structures change from 2-D sheet-like compounds for 1 and 2 to 0-D dimeric species for 3 and 4. A water cluster (H₂O)₁₈ exists in 3, which further assembles into a water tape with a new pattern T4(3)4(3)10(3)A4. Complex 3 loses crystallinity rapidly in the open air and turns into [Pb(5-msba)(phen)₂]·2H₂O (3A). Thermal stabilities and solid state fluorescent properties of 1, 2, 3A, and 4 have been studied.     

吡啶基咪唑[4,5-f]1,10-菲咯啉合成、表征及与瓜环作用的光谱学考察

设计合成了2个吡啶基菲咯啉衍生物2-(3-吡啶基)咪唑[4,5-f]1,10-菲咯啉(G1)和2-(4-吡啶基)咪唑[4,5-f]1,10-菲咯啉(G2),通过元素分析、质谱和核磁共振氢谱对其结构进行了表征。 利用紫外吸收光谱和荧光光谱法考察了所合成化合物与六元瓜环Q[6]、七元瓜环Q[7]的相互作用,以及体系pH值对主-客体相互作用的影响。 在酸性条件下,Q[6]、Q[7]与Gl以及Q[6]与G2均发生包合形成1∶1的包合物,并有荧光增敏作用;Q[7]与G2作用形成1∶2包合物,且对G2有荧光猝灭作用;Q[6]、Q[7]与G1的包合常数分别为3.00×104和1.86×104 L/mol;Q[6]、Q[7]与G2的包合常数分别为1.64×104和1.01×103 L/mol。 随着体系酸性减弱,瓜环与客体作用减弱,在中性条件下,瓜环未与客体发生包合作用。     

Cytotoxicity,apoptosis, interaction with DNA,cellular uptake,and cell cycle arrest of ruthenium(II) polypyridyl complexes containing 4,4′-dimethyl-2,2′-bipyridine as ancillary ligand

Two new ruthenium(II) polypyridyl complexes, [Ru(dmb)₂(DNPIP)](ClO₄)₂ (1) (DNPIP?=?2-(2,4-dinitrophenyl)imidazo[4,5-f][1,10]phenanthroline, dmb?=?4,4′-dimethyl-2,2′-bipyridine) and [Ru(dmb)₂(DAPIP)](ClO₄)₂ (2) (DAPIP?=?2-(2,4-diaminophenyl)imidazo[4,5f][1,10]phenanthroline), were synthesized and characterized. The DNA-binding behaviors of these complexes have been studied by UV-Vis absorption titration, viscosity measurements, and photocleavage. The DNA-binding constants are 7.39 (±0.16)?×?10⁴ (s?=?2.68) and 2.73 (±0.16)?×?10^4?(mol?L^?1)^?1 (s?=?0.64) for 1 and 2, respectively. Their evaluation as cytotoxic agents on different cancer cell lines was investigated with IC₅₀ values of 59.5, 51.3, and 70.3?µmol?L^?1 for 1, >100, 87.9, and 77.9?µmol?L^?1 for 2 against BEL-7402, HepG-2, and MCF-7 cells, respectively. Complex 1 is more active than 2 against selected cancer cell lines. The apoptosis induced by these complexes was studied. Cellular uptake showed that these complexes could enter into the cytoplasm and accumulate in the nuclei. The cell cycle arrest and antioxidant activity against hydroxyl radicals were also investigated.     

Spectroscopy studies on DNA binding of two ruthenium complexes [Ru(MeIm)4(L)]2+ (L = iip and tip)

Two ruthenium(II) complexes [Ru(MeIm)₄(L)]²⁺ (L?=?2-(imidazo-4-group)-1H-imidazo-[4,5-f][1,10]phenanthroline, 2-(thiophene-2-group)-1H-imidazo[4,5-f][1,10]phenanthroline, MeIm?=?1-methylimidazole) have been synthesized according to literature and structurally characterized. The interaction of the complexes with calf thymus DNA has been explored using electronic absorption titration, competitive binding experiment, circular dichroism, thermal denaturation, and viscosity measurements. The results show that both complexes could bind DNA in a intercalation mode and the DNA-binding affinity of [Ru(MeIm)₄(tip)]²⁺ (K _b?=?(7.2?±?0.3)?×?10⁵?(mol?L^?1)^?1) is greater than that of [Ru(MeIm)₄(iip)]²⁺ (K _b?=?(6.1?±?0.2)?×?10⁵?(mol?L^?1)^?1).     

DNA-binding,antioxidant activity and in vitro cytotoxicity induced by ruthenium(II) complexes containing polypyridyl ligands

Two new ruthenium(II) polypyridyl complexes, [Ru(dmp)₂(maip)](ClO₄)₂ 1 (maip = 2-(3-aminophenyl)imizado[4,5-f][1,10]phenanthroline and [Ru(dmp)₂(paip)](ClO₄)₂ 2 (paip = 2-(4-aminophenyl)imidazo[4,5-f][1,10]phenanthroline, dmp = 2, 9-dimethyl-1,10-phenanthroline) have been synthesized and characterized. The DNA-binding behaviors of complexes 1 and 2 were studied by viscosity measurements, thermal denaturation, and absorption titration. The results show that the two complexes intercalate between the base pairs of DNA. The DNA-binding constants K _b for complexes 1 and 2 were determined to be 3.23 ± 0.16 × 10⁴ M⁻¹ (s = 0.97) and 4.34 ± 0.65 × 10⁴ M⁻¹ (s = 1.13). The cytotoxicity of these complexes has been evaluated by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. The IC₅₀ values are 35.70, 41.04, 55.25 and 37.50 for complex 1 and 37.02, 103.08, 130.07 and 37.80 for complex 2 against BEL-7402, C-6, HepG-2 and MCF-7 cell lines, respectively. The antioxidant activity against hydroxyl radical (OH•) was also investigated.     

Structure and magnetism of a new 2-D trinuclear Mn(II) polymer

A new complex, {[Mn₃(oba)₂(IP)₂(CH₃COO)₂]·H₂O}_n (1) (H₂oba?=?4,4′-oxybis(benzoic acid), IP?=?1-H-imidazo[4,5-f][1,10]-phenanthroline), has been synthesized and structurally characterized by single-crystal diffraction analysis. The structural determination revealed that 1 has a 2-D grid motif, which can be further linked into a 3-D porous network via packing interactions. The magnetic properties of 1 are discussed.