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Here, a hexanuclear Co

Inspired by natural 2-quinolinecarboxylic acid derivatives, a series of quinoline compounds containing acylhydrazine, acylhydrazone, sulfonylhydrazine, oxadiazole, thiadiazole, or triazole moieties were synthesized and evaluated for their fungicidal activity. Most of these compounds exhibited excellent fungicidal activity in vitro. Significantly, compound 2e displayed the superior in vitro antifungal activity against Sclerotinia sclerotiorum, Rhizoctonia solani, Botrytis cinerea, and Fusarium graminearum with the EC50 values of 0.39, 0.46, 0.19, and 0.18 μg/mL, respectively, and were more potent than those of carbendazim (EC50, 0.68, 0.14, >100, and 0.65 μg/mL, respectively). Moreover, compound 2e could inhibit spore germination of F. graminearum. Preliminary mechanistic studies showed that compound 2e could cause abnormal morphology of cell walls and vacuoles, loss of mitochondrion, increases in membrane permeability, and release of cellular contents. These results indicate that compound 2e displayed superior fungicidal activities and could be a potential fungicidal candidate against plant fungal diseases.

Phytopathogenic fungal infections have become a major threat to agricultural production, food security, and human health globally, and novel antifungal agents with simple chemical scaffolds and high efficiency are needed. In this study, we designed and synthesized 38 8-hydroxyquinoline metal complexes and evaluated their antifungal activities. The results showed that most of the tested compounds possessed remarkable in vitro antifungal activity. Especially, compound 1e exhibited the highest antifungal potency among all target compounds, with EC50 values of 0.0940, 0.125, 2.95, and 5.96 μg/mL, respectively, against Sclerotinia sclerotiorum, Botrytis cinerea, Fusarium graminearum, and Magnaporthe oryzae. Preliminary mechanistic studies had shown that compound 1e might cause mycelial abnormalities of S. sclerotiorum, cell membrane permeability changes, leakage of cell contents, and inhibition of sclerotia formation and germination. Moreover, the results of in vivo antifungal activity of compound 1e against S. sclerotiorum showed that 1e possessed higher curative effects than that of the positive control azoxystrobin. Therefore, compound 1e is expected to be a novel leading structure for the development of new antifungal agents.

The novel sulfonate-carboxylate ligand of 5,7-disulfonate-1,4-naphthalenedicarboxylic acid (H4-DSNPDC) was synthesized, and its series of lanthanide compounds {[Ln3(μ2-OH)(DSNPDC)2(H2O)x]·yH2O}n (J...

A novel fluorinated biphenyldicarboxylate ligand of 3,3',5,5'-tetrafluorobiphenyl-4,4'-dicarboxylic acid (H2-TFBPDC) and its terbium metal-organic framework, {[Tb2(TFBPDC)3(H2O)]·4.5DMF·0.5H2O}n (denoted as JXNU-6), were synthesized. JXNU-6 exhibits a three-dimensional (3D) framework built from one-dimensional (1D) terbium carboxylate helical chains bridged by TFBPDC2- linkers. The 3D framework of JXNU-6 features 1D fluorine-lined channels. The gas adsorption experiments show that the activated JXNU-6 (JXNU-6a) displays distinct adsorption behavior for propyne (C3H4) and propylene (C3H6) gases. The effective removal of a trace amount of C3H4 from C3H6 was achieved by JXNU-6a under ambient conditions, which is demonstrated by the column-breakthrough experiments. The modeling studies show that the preferential binding sites for C3H4 are the exposed F atoms on the pore surface in 1D channels. The strong C-H···F hydrogen bonds between C3H4 molecules and F atoms of TFBPDC2- ligands dominate the host-guest interactions, which mainly account for the excellent C3H4/C3H6 separation performance of JXNU-6a. This work provides a strategy for specific recognition toward C3H4 over C3H6 through the C-H···F hydrogen bond associated with the fluorinated organic ligand.

Due to the intrinsic coordination preference of the linear uranyl unit, uranyl-organic frameworks (UOFs) are generally prone to exhibiting low-dimensional structures. Reactions of uranyl nitrate with biphenyl-3,3'-disulfonyl-4,4'-dicarboxylic acid dipotassium salt (K2H2BPDSDC) under different conditions led to three UOFs, namely, {(Me2NH2)[K2(UO2)3(μ3-O)(μ3-OH)2(μ2-OH)(BPDSDC)(H2O)3]·4DMF}n (1), {[K2(UO2)(μ3-O)(BPDSDC)0.5(H2O)2]}n (2), and {(Me2NH2)2.5[K1.5(UO2)(BPDSDC)1.5(H2O)3]}n (3). Compounds 1 and 2 contain one-dimensional (1D) ribbon structures formed from UO22+ units bridged by μ3-O atoms and carboxylate groups. The 1D ribbons in 1 are linked by K+ atoms to form a two-dimensional (2D) layer, which is further pillared by the biphenyl units to give a three-dimensional (3D) framework. For 2, the oxygen atoms of UO22+ units in each 1D ribbon bridge the K+ atoms to form four -[K-O-K]n- infinite chains located above and below the ribbon. The 1D ribbons in 2 are bridged by sulfonate groups to generate a 3D substructure featuring 1D channels occupied by biphenyl moieties. In 3, each mononuclear [(UO2)(COO)3] unit is bridged by three K+ atoms to form a 3D substructure featuring 1D small left-handed and large righted helical channels occluded by biphenyl moieties. Compound 2 exhibits an excellent proton conductivity with the highest conductivity of 1.07 × 10-3 S cm-1. The inner walls of 1D channels of 2 are full of the hydrophilic sulfonate groups, which boost enrichment of the guest water molecules, thus resulting in a high proton conductivity. Finally, temperature dependence of fluorescent studies showed that compounds 1 and 2 display the characteristic uranyl emissions. This work presents the elegant examples of the rarely explored 3D UOFs and expands the potentials of UOFs.

It is valuable to develop a sensing platform for not only detecting a tumor marker in body fluids but also measuring its expression at single cells. In the present study, a simple closed bipolar electrodes-based electrochemiluminescence (BPEs-ECL) imaging strategy was developed for visual immunoassay of prostate specific antigen (PSA) at single cells using functional nanoprobes of heterogeneous Ru(bpy)32+@SiO2/Au nanoparticles. Multiple-assisted ECL signal amplification strategy was introduced into the detection system on the basis of the synergetic amplifying effect of the anodic and cathodic amplification. On the basis of the synergetic amplifying effect, the detection limits of PSA by using photomultiplier tube and charge-coupled device (CCD) imaging are 3.0 and 31 pg/mL, respectively. The obtained immunosensor was employed to evaluate PSA levels in serum samples with a satisfying result. Moreover, the obtained functional nanoprobes were used to visually profile the PSA expression on the surface of sin...

A metal–organic framework (MOF), {(Me2NH2)2[Zn6(μ4-O)(ad)4(BPDC)4]}n (JXNU-4; ad– = adeninate), with an anionic three-dimensional (3D) framework constructed from one-dimensional (1D) columnar [Zn6(ad)4(μ4-O)]n secondary building units (SBUs) and 4,4′-biphenyldicarboxylate (BPDC2–) ligand, was prepared. The anionic 3D framework has 1D square channels with an aperture of about 9.8 A and exhibits a carboxylate-O-decorated pore environment. The microporous nature of JXNU-4 was established by the N2 adsorption data, which gives Langmuir and Brumauer–Emmett–Teller surface areas of 1800 and 1250 m2 g–1, respectively. Noticeably, JXNU-4 shows potential as a separation agent for the selective removal of propane and ethane from natural gas with high selectivities of 144 for C3H8/CH4 (5:95) and 14.6 for C2H6/CH4 (5:95), respectively. Most importantly, JXNU-4 shows an aqueous-phase adsorption of a positively charged ion of methylene blue selectively over a negatively charged ion of resorufin, which is pertinent to th...

A novel sulfonate-carboxylate ligand of biphenyl-3,3'-disulfonyl-4,4'-dicarboxylic acid (H4-BPDSDC) and its lanthanide-organic frameworks {[LnK(BPDSDC)(DMF)(H2O)]·x(solvent)}n (JXNU-2, where JXNU denotes Jiangxi Normal University, DMF indicates dimethylformamide, and Ln = Sm(3+), Eu(3+), and Pr(3+)) were synthesized and structurally characterized. The three isomorphous lanthanide compounds feature three-dimensional frameworks constructed from one-dimensional (1D) rod-shaped heterometallic Ln-K secondary building units and are an illustration of a Kagome-like lattice with large 1D hexagonal channels and small 1D trigonal channels. The porous material of the representive JXNU-2(Sm) has an affinity to quadrupolar molecules such as CO2 and C2H2. In addition, the JXNU-2(Sm) compound exhibits humidity- and temperature-dependent proton conductivity with a large value of 1.11 × 10(-3) S cm(-1) at 80 °C and 98% relative humidity. The hydrophilic sulfonate group on the surface of channels facilitates enrichment of the solvate water molecules in the channels, which enhances the proton conductivity of this material. Moreover, the JXNU-2(Eu) material with the characteristic bright red color shows the potential for recognition of K(+) and Fe(3+) ions. The enhancing Eu(3+) luminescence with the K(+) ion and quenching Eu(3+) luminescence with the Fe(3+) ion can be associated with the functional groups of the organic ligand.

A series of dinuclear Dy(III) compounds with the general formula [Dy2(μ2-anthc)4(anthc)2(L)2] (anthc(-) = 9-anthracenecarboxylate, L = 2,2'-bipyridyl (1), 1,10-phenanthroline (2), and 4,7-dimethyl-1,10-phenanthroline (3)) were synthesized and magnetically characterized. These compounds exhibit single-molecule magnet (SMM) behavior in the absence of the direct-current field, which is rarely observed for carboxylate-bridged dinuclear Dy2 system. With the first coordination sphere of Dy(III) centers being fixed, the energy barrier was modulated by sequentially modifying the terminal neutral L ligands in this Dy2 system. Theoretical calculations revealed that the symmetry of the charge distribution surrounding the Dy(III) centers in 1-3 is the decisive factor to determine the relaxation of the SMMs. The combination of the larger charge distribution along the magnetic axis and lower charge distribution in the equatorial plane (hard plane) formed by five coplanar coordination atoms including two N atoms provided by an L ligand led to a strong easy-axis ligand field in these compounds. This work presents a rational method to modulate the dynamic magnetic relaxation of the lanthanide SMMs through fine-tuning electrostatic potential of the atoms on the hard plane.

A new compound, {[Co(bmzbc)(2)]center dot 2DMF}(n) (JXNU-1, JXNU denotes Jiangxi Normal University), based on the 4-(benzimidazole-1-yl)benzoate (bmzbc(-)) ligand has been synthesized and structurally characterized. The Co(II) ions are bridged by the rod-like bmzbc(-) ligands to give a two-dimensional (2D) sheet wherein the Co(II) ions are spatially separated from each other by the long bmzbc- rods. The 2D sheets are further stacked into a 3D framework with ID channels occluding the guest DMF molecules. Detailed magnetic studies show that the individual octahedral Co(II) ions in JXNU-1 exhibit field-induced slow magnetic relaxation, which is characteristic behavior of single-ion magnets (SIMs). The rarely observed positive value of zero-field splitting (ZFS) parameter D for the Co(II) ion in JXNU-1 demonstrates that JXNU-1 is a unique example of Co(II)-based SIMs with easy-plane anisotropy, which is also confirmed by the calculations. The microporous nature of JXNU-1 was established by measuring CO2 sorption isotherms. The abrupt changes observed in the C3H8 and C2H6 adsorption isotherms indicate that a structural transformation occurred in the gas-loading process. The long connection between the magnetic metal centers in JXNU-1 meets the requirements for construction of porosity and SIM in a well-defined network, harmoniously providing a good candidate of functional molecular materials exhibiting SIM and porosity.

An organic ligand 4-(1,2,4-triazol-1-yl) benzoic acid (Htzbc) with a nonlinear optical (NLO) chromophore has been synthesized. Reaction of Zn(NO3)2 with Htzbc ligand in 1-n-butyl-3-methylimidazolium tetrafluoroborate ionic liquid afforded compound Zn(tzbc)2 (1). The Htzbc organic solid and 1 crystallize in the acentric Pn and Cc space groups, respectively. The tetrahedral Zn2+ center in 1 coordinates to two triazole nitrogen atoms and two carboxylate oxygen atoms from four tzbc– ligands, leading to a noncentrosymmetric 5-fold interpenetrating diamondoid network. Second-harmonic generation (SHG) measurements revealed the Htzbc solid and 1 have SHG activities. The Htzbc compound has a large SHG effect, which is approximately 3 times that of KDP and is type-I phase matchable, while 1 also belongs to phase-matchable class with a SHG response of about 1.2 times that of KDP. The SHG active of the organic solid can be derived from the inherently dipolar Htzbc molecule as well as the optimal relative orientation ...

A sulfonate-carboxylate ligand, 4,8-disulfonyl-2,6-naphthalenedicarboxylic acid (H(4)-DSNDA), and eight new lanthanide coordination polymers {[Pr(4)(OH)(4)(DSNDA)(2)(H(2)O)(12)](H(2)O)(10)}(n) (1), [Ln(H(2)-DSNDA)(0.5)(DSNDA)(0.5)(H(2)O)(5)](n) (Ln = La(2), Nd(3), Sm(4), Eu(5), Gd(6), and Dy(7)), and {[Er(H-DSNDA)(H(2)O)(4)](H(2)O)}(n) (8) have been synthesized. Detailed crystal structures of these compounds have been investigated. Compound 1 has a 3D framework featuring the unique cubane-shaped [Pr(4)(μ(3)-OH)(4)] clusters and is a binodal 4,8-connected network with (4(16)·6(12))(4(4)·6(2))(2) topology. Compounds 2-7 are isostructural and have 2D layered structures. Compound 8 is also a 2D layer but belongs to different structural types. The luminescence behavior of compound Eu(5) shows that the π-rich aromatic organic ligands efficiently transfer the absorbed light energy to the Eu(III) ions, thus enhancing the overall luminescent properties of compound Eu(5). The magnetic properties of all compounds except for the diamagnetic La(2) compound have been investigated. In addition, elemental analysis, IR spectra, and thermogravimetric analysis of these compounds are also described.

Two homochiral enantiomers {(EMIM)[Zn(SIP)(IM)]}n (1a and 1b, EMIM = 1-ethyl-3-methylimidazolium) possessing chiral (10,3)-a topology constructed from an achiral rigid 5-sulfoisophthalate (SIP) ligand and imidazole (IM) have been obtained by spontaneous resolution under ionothermal conditions. The homochiral enantiomers show second-order nonlinear optical effects and photoluminescence.

Solvo(hydro)thermal reactions of CuX (X = Cl, Br, I) with 4-methyl-1,2,4-triazole-3-thiol (Hmptrz) ligand afforded four new copper(I) coordination polymers, namely, [Cu(μ4-mptrz)]n (1), [Cu(μ2-Hmptrz)(μ2-I)]n (2), [Cu12(μ4-mptrz)4(μ4-I)3(μ3-I)4(μ2-I)]n (3), and [Cu(μ2-Hmptrz)(μ2-DmptrzSS)I]n (4) (DmptrzSS = 4,4′-dimethyl-3,3′-dithiodi-1,2,4-triazole), respectively. Single-crystal X-ray diffraction revealed that compound 1 has a two-dimensional (2D) layered structure with (44·62) topology and contains meso-helical (CuS)n chains. Compound 2 features a one-dimensional (1D) chain structure constructed from an unusual inorganic [Cu(μ2-S)2Cu(μ2-I)2Cu]n chain formed from two types of four-membered Cu2(μ2-S)2 and Cu2(μ2-I)2 rings. Compound 3 is a two-dimensional (2D) structure constructed from rugby-shaped Cu6I5 and planar Cu4I3 cluster units, and two types of Cu(mptrz)2 units. The I− ion in structure 3 displays its coordination versatility with μ4-, μ3-, and μ2- bridging coordination modes. Compound 4 has a doub...