PRELIMINARY STUDIES ON THE SYNTHESIS AND CHARACTERIZATION OF OXY-AND THIO-DIACETIC ACID HYDRAZITION AND THEIR FIRST-ROW TRANSITION METAL COMPLEXES

It has been made certain that thio-and oxy-diacetic acid hydrazides are potential anticancer compounds.However,their ability to form complexes with transition metals and the properties of the complexes thus formed have not been studied.Employing a new potential anticancer ligand 1,2-bis(thioacetic acid hydrazide)ethane prepared in our lab,along with ligands oxydiacetic hydrazide and 1,2-bis(oxyacetic acid hydrazide) ethane,a series of 11 new first-row transition metal(M=Zn^(2+),Cu^(2+),Co^(2+), Ni^(2+))complexes with each of the above three ligands have been synthesized and characterized by means of elemental analyses,IR,TG and X-ray powder diffraction.

Biochemical Characterization of Soluble Acid and Alkaline Invertases from Shoots of Etiolated Pea Seedlings

Soluble invertase was purified from pea （Pisum sativum L.） by sequential procedures entailing ammonium sulfate precipitation, DEAE-Sepharose column, Con-A- and Green 19-Sepharose affinity columns, hydroxyapatite column, ultra-filtration, and Sephacryl 300 gel filtration. The purified soluble acid （SAC） and alkaline （SALK） invertases had a pH optimum of 5.3 and 7.3, respectively. The temperature optimum of two invertases was 37 ℃. The effects of various concentrations of Tris-HCI, HgCI2, and CuSO4 on the activities of the two purified enzymes were examined. Tris-HCI and HgCI2 did not affect SAC activity, whereas 10 mM Tris-HCI and 0.05 mM HgCI2 inhibited SALK activity by about 50%. SAC and SALK were inhibited by 4.8 mM and 0.6 mM CuSO4 by 50%, respectively. The enzymes display typical hyperbolic saturation kinetics for sucrose hydrolysis. The Kms of SAC and SALK were determined to be 1.8 and 38.6 mM, respectively. The molecular masses of SAC shown by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunoblotting were 22 kDa and 45 kDa. The molecular mass of SALK was 30 kDa. Iso-electric points of the SAC and SALK were estimated to be about pH 7.0 and pH 5.7, respectively.

Synthesis and characterization of acetylated sept-D-glucopyranose carbamate as an oligosaccharide donor

An oligosaccharide donor, acetylated sept-o-glucopyranose tetradecyl carbamate, was designed and synthesized. This compound could be easily linked to hydroxyl-containing compounds through an Oglycosidic bond. Characterization of all the oligosaccharide intermediates and the final product was thoroughly discussed.

Convenient synthesis and application of novel bi-SO_3H-functionalized ionic liquids based on piperazinium

In this article, series of novel bi-SOaH-functionalized ILs were synthesized using simple, efficient and economic procedure. Hammer method had been used to determine the acidity order of these ionic liquids, and the acidifies of bi-SOaH-functionalized ILs were stronger than that of traditional single-SOaH-functionalized ILs. Their catalytic activities in the synthesis of N-（3-phenyl）-3- oxo-1-（phenylpropyl）acetamide were investigated and they were consistent with their acidities.

Acidic Ionic Liquids as Efficient and Environmentally Benign Medium for the Synthesis of 2-Phenylbenzimidazole

2-Substituted benzimidazoles have been synthesized in excellent yields under solvent-free conditions using a series of acidic ionic liquids as catalysts. The results indicate that SO3H-functionalized ionic liquids show higher catalytic activities than other acidic ionic liquids. The effects of reaction conditions such as the amounts of ionic liquids, the ratio of reactants were investigated. A Hammett method was used to determine the acidity order of these ionic liquids and the results were found to be relevant to the catalytic activities observed in the synthesis reaction. Besides, the reaction mechanism was stimulated using DFT method.

The effect of oxidation on physicochemical properties and aqueous stabilization of multiwalled carbon nanotubes：comparison of multiple analysis methods

Surface oxidation can alter physicochemical properties of multiwalled carbon nanotubes(MWCNTs) and influence their aqueous stabilization.Many techniques have been used to characterize the physicochemical properties and aqueous stabilization of MWCNTs.However,the relationship between the change in physicochemical property and the aqueous stabilization of MWCNTs merits more studies,and the multiple characterization techniques have not been well compared.This study systematically and comparatively investigated the effect of oxidation on the physicochemical properties and aqueous stabilization of MWCNTs using multiple analysis methods.Increased surface area,disclosed tube ends,defects on the sidewalls,disruption of the electronic structure,and removal of metal catalysts and amorphous carbon were observed for the oxidized MWCNTs(o-MWCNTs) using the multipoint Brunauer-Emmett-Teller(BET) method,transmission electron microscope observation,Raman spectroscopy,UV-Vis spectroscopy,and thermogravimetric analysis.An oxidation-time-dependent increase in oxygen content of the MWCNTs was verified by the methods of elemental analysis,mass difference calculation,and X-ray photoelectron spectroscopy(XPS).Fourier transform infrared spectroscopy,XPS,and the Boehm titration were employed to study the functionalities on the MWCNT surfaces.Despite the limitations of these techniques,the results indicated that the dramatic increase in carboxyl groups was mainly responsible for the significant increase in oxygen content after the oxidation.The dissociation of the grafted functional groups increased electronegativity of the o-MWCNTs and facilitated the aqueous stabilization of o-MWCNTs through electrostatic repulsions.The oxidation affected the UV-Vis absorbance of MWCNT suspensions.The absorbances at 800 nm of the stabilized MWCNT suspensions had a good correlation with the MWCNT concentrations and could be used to quantify the MWCNT suspensions.The findings of this work are expected to boost the research on carbon nanotubes and their environmental behaviors.