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In this paper, a novel bismuthoxide Schiff-base complex [Bi9O8(vanen)3(NO3)2(CH3OH)2(H2O)·3NO3·5.5H2O](abbreviated as Bivanen) was synthesized with Salen-like ligand[H2vanen=N,N’-ethylene bis(3-methoxy-salicylideneimine)] and bismuth(III) nitrate. Its structure was characterized by IR spectra, NMR spectra and X-ray diffraction. In particular, the biology activities of the ligand and the complex against Schizosaccharomyces pombe (S. pombe) were studied using biological microcalorimetry. The metabolic thermogenic curves of S. pombe were measured at 32.00 °C. Then, some quantitative thermokinetic parameters of growth metabolism of S. pombe including the rate constant(k), inhibition ratio(I) and half inhibition concentration(IC50) were calculated. Experimental results showed that the k values of S. pombe decreased while I values of S. pombe increased with the increase of concentrations of the ligand and the complex. The IC50 of the ligand and the complex were found to be 0.067 and 0.037 mmol/L, respectively.

In this paper, a new bismuth(III) Schiff-base complex [Bi9O8(vanen)3(NO3)2(CH3OH)2(H2O)]·3NO3·5.5H2O was synthesized by reaction of [H2vanen = N,N′-ethylene bis(3-methoxysalicylideneimine)] and Bi(NO3)3·5H2O in methanol at 45–60 °C. The inhibitory effects of the complex and its ligand on Schizosaccharomyces pombe (S. pombe) growth were investigated by microcalorimetry. The experimental results indicated the complex had a stronger inhibitory activity towards S. pombe than that of the ligand. The interaction between bovine serum albumin (BSA) and the complex under physiological conditions was studied by fluorescence spectroscopy. The complex had a quite strong ability to quench the fluorescence of BSA and their combination reactions were a static quenching process. The complex could bind BSA via a binding site and the binding distance r was 3.52 nm. The synchronous fluorescence spectroscopy further revealed that the complex had partly inserted into the hydrophobic pocket of BSA.

The first investigation of chiral ruthenium(II) complexes Δ- and Λ-[Ru(bpy)

A mononuclear salen-type complex [Cu( vanen )(H 2 O)] was synthesized from the ligand [H 2 vanen = N , N - ethylene-bis(3-methoxysalicylideneimine)] and Cu(OAc) 2 ·H 2 O. Based on Hess law, a reasonable thermochemical cycle was designed. According to the cycle, the standard molar enthalpies of dissolution of samples in the calorimetric solvent of DMF ( N , N -dimethylformamide) were determined, respectively. The standard molar enthalpy change of the coordination reaction (Δ r H m θ ) was calculated to be -(16.61 ± 0.54) kJ/mol. Combined with some relevant literature data, the standard molar enthalpy of formation (Δ f H m θ ) of the complex was obtained to be -(756.5 ± 2.4) kJ/mol. At the temperature of 32 ℃, the metabolic thermogenetic curves of S. pombe under the influence of the complex with different concentration were determined by using a TAM air isothermal calorimeter. The relationships of the concentration of the complex with the microbial growth rate constant ( k ) of S. pombe , inhibition ratio (I), the half inhibition concentration (IC 50 ), the maximum heat output power ( P max ) and the time it took ( t max ) were analyzed. The results indicated that the complex possessed the Hormesis effect, which promoted the growth of S. pombe at lower concentration, but inhibited the growth at higher concentration.

The title complex [Pr(H 2 vanen )(NO 3 ) 2 (H 2 O) 2 ·NO 3 ] was synthesized reacting of Valen Schiff-base ligand [H 2 vanen = N , N ′-ethylene-bis(3-methoxysalicylideneimine)] and Pr(NO 3 ) 3 ·6H 2 O in ethanol at 60 °C. The complex was crystallized in the monoclinic crystal system with space group P21/c. The coordination polyhedron of Pr(III) ion was consisted of two bidentate nitrate ions, two molecules of water and one ligand which coordinated through oxygen atoms of the two phenolic and methoxy groups. After designing two reasonable thermochemical cycles according to Hess's law, the calorimetric experiments were conducted using isoperibol solution–reaction calorimeter at a constant temperature of 298.15 K. The standard molar enthalpy changes of two reactions were determined to be Δ r H m θ ( 1 a ) = − ( 51.94 ± 1.26 ) kJ mol −1 and Δ r H m θ ( 1 b ) = − ( 8.62 ± 1.34 ) kJ mol −1 . Then the standard molar enthalpies of formation of the ligand and the title complex were calculated to be Δ f H m θ [H 2 vanen (s), 298.15 K] = −(517.75 ± 2.36) kJ mol −1 and Δ f H m θ [Pr(H 2 vanen )(NO 3 ) 2 (H 2 O) 2 ·NO 3 (s), 298.15 K] = −(2454.8 ± 2.7) kJ mol −1 , respectively. The rationality of two thermochemical cycles was verified by UV spectra and refractive indexes.

In this paper, the one-step synthesis of N-bromoamino acids has been developed by electrolyzing imines and carbon dioxide (4 MPa). The electrosynthesis was performed in an undivided cell with Ni cathode and Al sacrificial anode containing n-Bu4NBr–DMF as supporting electrolyte with a constant current at room temperature. The N-bromoamino acids were afforded in moderate to good yields rather than traditional α-amino acids. To explore the truth, some influenced factors (cathode materials, supporting electrolyte, and electricity etc.) were investigated. The experimental results indicated that the NH group of the α-amino acid could be deprotonated by alkyl anion R− (carbanion, a strong base), followed by the oxidation of hypobromous acid resulted from the two-step oxidation of the bromide ion at the anode, and produced the N-bromoamino acid. Finally, the reaction mechanism was briefly discussed.

The Schiff-base ligand [H2salen = N,N′-bis(salicylidene) ethylendiamine] and the binuclear copper (II) complex [Cu2(salen)2(μ − O)2] were synthesized and the structure of the complex was characterized by X-ray crystallography. Two thermochemical cycles were designed on basis of Hess's law. According to the two cycles, the dissolution enthalpies of relevant substance in the calorimetric solvent of DMF were determined by a solution-reaction isoperibol calorimeter. The measurement experiment was performed at a constant ambient temperature of 298.15 K. After that, the rationality of these two thermochemical cycles was demonstrated by UV spectra and refractive indexes. Base on the measurement results and relevant literature data, the standard molar enthalpies of formation of the Schiff base and the complex were reckoned to be: Δ f H m θ [ H 2 salen ( s ) , 298.15 K ] = − ( 146.4 ± 1.9 ) kJ mol − 1 ; Δ f H m θ [ Cu 2 ( salen ) 2 ( μ − O ) 2 ( s ) , 298.15 K ] = − ( 171.8 ± 3.9 ) kJ mol − 1 .

In this paper, the one-step synthesis of N-bromoamino acids has been developed by electrolyzing imines and carbon dioxide (4 MPa). The electrosynthesis was performed in an undivided cell with Ni cathode and Al sacrificial anode containing n-Bu4NBr–DMF as supporting electrolyte with a constant current at room temperature. The N-bromoamino acids were afforded in moderate to good yields rather than traditional α-amino acids. To explore the truth, some influenced factors (cathode materials, supporting electrolyte, and electricity etc.) were investigated. The experimental results indicated that the NH group of the α-amino acid could be deprotonated by alkyl anion R− (carbanion, a strong base), followed by the oxidation of hypobromous acid resulted from the two-step oxidation of the bromide ion at the anode, and produced the N-bromoamino acid. Finally, the reaction mechanism was briefly discussed.