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Dactylogyrus is one of the most common parasitic diseases in fish and causes huge losses to the aquaculture industry. With the advantages of safety, low toxicity and easy degradation, plant‐derived drugs are ideal for the creation of green aquatic ingredients. The use of plant‐derived drugs in aquaculture is limited by their low content and high processing costs, which is a challenge that can be solved by the chemical synthesis of plant‐derived drugs. Eleven new coumarin derivatives were synthesized and assessed for their anthelmintic activity in this study. Among them, the derivative 7‐((1‐tosyl‐1H‐1,2,3‐triazol‐4‐yl)methoxy)‐2H‐chromen‐2‐one (N11) has good anthelmintic activity and its mean anthelmintic efficacy against D. intermedius at a concentration of 10 μM reached 99.84%, which is even better than the anthelmintic activity of the positive control mebendazole. Further studies showed that N11 had concentration values of 3.31 and 1.94 μM for 50% maximal effect (EC50) against D. intermedius at 24 and 48 h, respectively. Furthermore, scanning electron microscopy revealed that N11 caused damage to D. intermedius. What is more noteworthy is that a substantial reduction in the ATP content of the parasite was observed following in vitro and in vivo administration of N11. Moreover, it was also found that N11 was able to inhibit the horizontal transmission of D. intermedius. Furthermore, real‐time quantitative PCR analysis was utilized to determine the expression profile of genes associated with anti‐inflammatory cytokines (IL‐10, TGF‐β and IL‐4) in goldfish. In all examined organs, it was observed that the expression of anti‐inflammatory cytokines increased subsequent to treatment with N11, according to the results. Thus, these results all suggest that N11 possesses good anthelmintic activity and is a potentially effective agent for the control of D. intermedius. [ABSTRACT FROM AUTHOR]

In language courses, it is important to foster students' systematic thinking and to develop their competence to express, appreciate, criticize and reflect, in particular in such courses as classical Chinese, which aim to develop students' cultural and literature knowledge. Problem posing is a promising strategy to achieve this objective. However, without sufficient supports, students could feel frustrated since problem posing is a challenging task, in particular for young students. In this study, a fill‐in concept mapping‐based problem‐posing approach was proposed to address this problem. A learning system was developed based on the proposed approach and a quasi‐experiment was conducted on an eighth‐grade classical Chinese course to evaluate the performance of the proposed approach. The experimental results show that the concept mapping‐based problem‐posing approach improved the students' learning achievement, critical thinking tendency and problem‐posing quality. The interview results further show that the students perceived the approach as being effective from the perspectives of "Improving article comprehension," "Improving problem‐posing performances," and "Boosting diverse thinking." [ABSTRACT FROM AUTHOR]

Herein, we describe a zinc‐catalysed N2‐selective olefination of benzotriazoles with unactivated alkenes and styrenes. The transformation is achieved by a N‐iodosuccinimide (NIS)‐mediated two‐step, one‐pot approach, proceeding through sequential regioselective β‐iodoalkylation of benzotriazoles with alkenes and a subsequent base‐promoted 1,2‐elimination. The N2‐selective β‐iodoalkylation of benzotriazoles is highly stereospecific and works under very simple and mild conditions, exhibiting excellent functional group tolerance. The high N2‐selectivity is attributed to intermolecular hydrogen bonding between the N‐iodosuccinimide and the NH hydrogen bond donor at the 1‐position of the benzotriazoles. This scalable process, serving as an efficient method for modular assembly of structurally diverse N2‐olefinated benzotriazoles, will significantly contribute to the chemistry of N2‐functionization of benzotriazoles. [ABSTRACT FROM AUTHOR]

Two unique dodecanuclear lanthanide clusters, [LnIII12Na3(µ3-OH)2(hmmp)6(piv)12(CO3)6(MeOH)6]OH ·5MeOH {Ln = Gd3+, Dy3+; hmmpH2 = 2-[(2-hydroxyethylimino)methyl]-6-methoxyphenol}, have been synthesized by treating the simple Schiff-base ligand hmmpH2 with the relevant lanthanide chloride and sodium pivalate (NaPiv). Single-crystal X-ray diffraction analysis revealed that the central cores of Gd12 and Dy12 are unprecedented and composed of a distorted four-layer triangular shelf-like molecular structure, which can be broken down into two types of four parallel triangular layers with an ABBA arrangement. Magnetic investigations revealed that the Gd12 cluster is a good candidate for magnetic refrigeration with a significant entropy change (-Δ Sm) of 30.99 J kg-1 K-1 for H = 7 T at 4 K, whereas the Dy12 cluster shows single-molecule magnet behavior. [ABSTRACT FROM AUTHOR]

The polymers [Cd(L)(H2O)] ( 1) and [Zn(L)(4, 4′-bipy)(H2O)3] ( 2) (L = 2, 2-dimethylsuccinated anion) were synthesized under hydrothermal conditions and characterized by IR spectrosopy, elemental analyses, and single-crystal X-ray diffraction analysis. The latter reveals that the polymer 1 exhibits a four-connected dia-topology net based on the novel tetranuclear CdII units, whereas polymer 2 displays a 4-connnected CdSO4 topology net. Moreover, the photoluminescent properties of 1 and 2 were investigated. [ABSTRACT FROM AUTHOR]

The syntheses, crystal structures, and magnetic properties of a novel family of heterometallic aggregates [CuII9LnIII2(μ3-OH)8(mea)4(C3H7COO)4(NO3)2Cl6(MeOH)4(H2O)2] ·3MeOH ·2H2O [Ln = Eu ( 1), Gd ( 2), Tb ( 3), Dy ( 4)] are reported. The compounds were obtained by the direct reaction of monoethanolamine (Hmea) with CuCl2 ·2H2O and Ln(NO3)3 ·6H2O in the presence of sodium butyrate (C3H7COONa) in MeOH/MeCN solution. Compounds 1- 4 are isomorphous and have an intriguing heterometallic undecanuclear [Cu9Ln2] core that contains a [3 × 3] [Cu9] grid and two [LnCu4] tetragonal pyramids that share a common [Cu4] vertex. Compounds 1- 4 are the first high-nuclearity 3d-4f aggregates bearing a monoethanolamine (Hmea) ligand to be reported. The magnetic properties of 1- 4 have been investigated by dc and ac susceptibility measurements. A detailed magnetic analysis revealed that antiferromagnetic Cu ···Cu interactions and ferromagnetic Cu ···Gd couplings exist in [Cu9Gd2] ( 2), which exhibits a significant magnetocaloric effect. Furthermore, [Cu9Tb2] ( 3) and [Cu9Dy2] ( 4) display slow relaxation of the magnetization. [ABSTRACT FROM AUTHOR]

Hydrogen-bond mediated coupling of 1,2,3-triazoles to indoles and pyrroles results in N2 selective functionalization of the triazole moiety in moderate to excellent yields. The reaction was tolerant of un-, mono- and disubstituted triazoles and was applied to synthesize tryptophan derived fluorescent amino acids. [ABSTRACT FROM AUTHOR]

Reactions of manganese perchlorate and a quinquedentate Schiff base ligand (H3 L), derived from o-vanillin and 3-amino-1,2-propanediol, together with a solution of coligands NaN3 or NaO2CH or NaO2CPh in methanol produced three new tetranuclear manganese clusters that contain a mixed-valent tetrahedral MnIIMnIII3 core with the corresponding general formula [NaMnIIMn3III(μ4-O2-)(H L)3(N3)3]ClO4 ·1.5H2O ( 1), [NaMnIIMn3III(μ4-O2-)(H L)3(HCO2)3]ClO4 ·4H2O ( 2), and [NaMnIIMn3III(μ4-O2-)(H L)3(PhCO2)(H2O)2](ClO4)2(PhCO2) ·PhCO2H ·H2O ·CH3OH ( 3). According to the feature of the tetrahedral MnIIMnIII3 core, we used a terephthalic acid disodium salt (Na2TA) instead of NaO2CPh and obtained an octanuclear manganese cluster that contained two tetrahedral MnIIMnIII3 cores bridged by a TA2- ligand with the general formula [Na2Mn2IIMn6III(μ4-O2-)2(H L)6(HCO2)2(CH3OH)2(TA)](TA)(ClO4)2 ·4CH3OH ·9.5H2O ( 4). Variable-temperature, solid-state direct-current (dc) magnetization studies were carried out on compounds 1- 4 in the 2.0-300 K range. The magnetic susceptibility data of these four compounds were fit to the theoretical χm T versus T expression derived by the use of an isotropic Heisenberg spin Hamiltonian and the Van Vleck equation. The fitting results revealed the presence of both antiferromagnetic and ferromagnetic interactions between the metal centers. [ABSTRACT FROM AUTHOR]

Two tetranuclear manganese complexes, [NaMnIIMn3III(μ4-O2-)(HL)3(SCN)4] ( 1) and [NaMnIIMn3III(μ4-O2-)(HL)3Cl4][NaMnIIMn3III(μ4-O2-)(HL)3Cl3(H2O)]ClO4 ·3.5H2O ( 2) were obtained from the reaction of manganese perchlorate with a quadridentate Schiff base ligand, 3-(2-hydroxybenzylideneamino)propane-1, 2-diol (H3L) derived from condensation of 2-hydroxybenzaldehyde with 3-amino-1, 2-propanediol, as well as the coligand KSCN or NaCl under basic conditions. Single-crystal X-ray studies reveal that those two complexes all have a mixed-valent tetrahedral core, which contains an apical MnII ion and three basal MnIII ions situated in the [Mn3(μ4-O2-)]7+ equilateral triangle plane. Fitting of the magnetic susceptibility data to the theoretical χm T vs. T expression, revealed that the presence of only antiferromagnetic interactions between the central metal atoms in 1, while both antiferromagnetic and ferromagnetic interactions are present in 2. [ABSTRACT FROM AUTHOR]

The one-pot reaction of nickel(II) perchlorate salt with NaN3 and the Schiff base ligand, 3-(2-hydroxybenzylideneamino) propane-1, 2-diol (H3L), derived from the condensation of 2-hydroxybenzaldehyde and 3-aminopropane-1, 2-diol, yields [Ni4(HL)2(H2L)2(N3)2] ·CH3CN ( 1). Single crystal X-ray studies reveal that the complex exhibits a tetranuclear face-shared defective double-cubane structure, having azido and alk/phenoxido bridges. Magnetic property of complex 1 was investigated using variable temperature magnetic susceptibility and both antiferromagnetic and ferromagnetic interactions exist in 1. On the basis of the known magneto-structural relationship of oxido-bridged nickel(II) complexes, the magnetic data were fitted and the parameters were given as g = 2.17, J1 = 9.22, J2 = 0.95, and J3 = -5.56. [ABSTRACT FROM AUTHOR]

A new tetranuclear manganese complex [Mn2IIMn2III(bhmcpH)2(hmp)4Cl2(MeOH)2] ( 1) [bhmcpH3 = 2, 6-bis(hydroxymethyl)-4-chlorophenol, hmpH = 2-(hydroxymethyl)pyridine] was synthesized and characterized. X-ray diffraction analyses reveal that complex 1 crystallizes in the monoclinic space group P21/ c. It has a mixed-valence tetranuclear dicubane unit, which comprises two MnII and two MnIII ions. The temperature dependence of the magnetic susceptibilities of 1 indicates ferromagnetic interactions between the manganese ions. [ABSTRACT FROM AUTHOR]

The reaction tolerates a wide range of substituents and functional groups, and proceeds with excellent selectivity. [ABSTRACT FROM AUTHOR]

Review: 58 refs. [ABSTRACT FROM AUTHOR]

The crystal structure of the title compound, [Co(3)(C(5)H(9)O(2))(6)O(CH(4)O)(3)]Cl, consists of trinuclear Co(III) complex cations and chloride anions. The Co(III) cation has site symmetry m, and is coordinated by four oxygen atoms from four bridging pivalate groups, one central O anion and a methanol oxygen atom, forming a distorted octa-hedral geometry. The coordinated methanol mol-ecule is located on a crystallographic special position, the C and O atoms being located on the mirror plane. The central O anion lies in the crystallographic position, and acts as a μ(3)-O bridge, linking three equivalent Co(III) cations and generating the oxo-centered trinuclear Co(III) complex. The chloride anion, which acts as the counter-ion, is located on crystallographic position. O-H⋯Cl hydrogen bonding between the Cl anion and hydroxyl group of the coordinated methanol mol-ecule links the mol-ecules into a supra-molecular network.

In the mononuclear title complex, [Cu(C(14)H(13)N(2)O(2))(2)], the Cu(II) atom lies on an inversion centre and adopts a square-planar coordination geometry. The dihedral angle formed by the pyridine and benzene rings is 74.61 (5)°. Intra-molecular C-H⋯O hydrogen bonds are present. The crystal structure is stabilized by weak aromatic π-π stacking inter-actions involving neighbouring pyridine rings [centroid-centroid distance = 3.853 (2) Å].

The title complex, [Co(2)Cl(4)(C(10)H(8)N(2))(2)(H(2)O)(2)], is composed of two Co(II) atoms, each hexa-coordinated by three Cl atoms, one 2,2'-bipyridine (bpy) ligand and one water mol-ecule in a distorted octa-hedral geometry. Neighboring Co(II) atoms are linked together by two Cl bridges, forming a dinuclear Co(II) complex with inversion symmetry. There are inter-molecular O-H⋯Cl hydrogen bonds and inter-molecular π-π stacking inter-actions between adjacent bpy ligands [centroid-centroid distance = 3.617 (2) Å] in the structure.