Reaction of 2-(4,5-dihydrofur-3-yl)-1,3-diphenyl-1,3-diaza-2-2λ3-phospholidine withC,N-diphenylnitriliminewithC,N-diphenylnitrilimine

The reaction of 2-(4,5-dihydrofur-3-yl)-1,3-diphenyl-1,3-diaza-2λ³-phospholidine withC,N-diphenylnitrilimine is a multistage process, in the course of which the 1,2,4-diazaphosphorine ring is formed and both rings of the initial organophosphorus compound are cleaved. 5-(2-Chloroethyl)-4-(N,N′-diphenylethylenediamino)-1,3-diphenyl-1,4-dihydro-1, 2,4λ⁵-diazaphosphorine was obtained as the final product. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 125–128, January, 2000.     

{[Ag(ATO)_2]CIO_4}_n的制备和分子结构

通过4-氨基-1,2,4-三唑-5-酮(ATO)水溶液与高氨酸银溶液反应,制备了聚高氨酸二(4-氨基-1,2,4-三唑-5-酮)合银(Ⅰ).并用X射线衍射、红外光谱和TG-DTG对其进行了结构表征.晶体属三斜晶系,空间群为P1,a=0.7534(1)nm,b=0.8505(1)nm,c=1.0257(1)nm;α=69.47(1)°,β=72.69(1)°,γ=86.00(1)°;V=0.5872(1)nm~3,Z=2,D_c=2.305g/cm~3,F(000)=400;偏离因子R为0.0358.中心银离子表现为较为特殊的三配位.     

Studies on Amidothiosemicarbazides and Related Hcterocyclic Derivatives ( XIII) --Synthetic Studies on 2-(3-Pyridyl)-5-Arylamino- 1,3, 4-Thiadiazoles and Oxadiazoles

By ring-closure of 1-nicotinyl-4-arylthiosemicarbazides under the catalysis of concentrated sulfuric acid or mercuric acetate, a series of 2-(3-pyridyl)-5-arylarnino-1,3,4-thiadiazoles and 2-(3-pyridyl)-5-ary-lamino-1,3,4-oxadiazoles were synthesized, respectively. All the products were subjected to testing of biological activity. Furthermore, the IR, 1H NMR and MS spectral properties of these new compounds were studied in details and some significant conclusions were drawn.     

硒功能化杯芳烃载体银离子选择性膜电极的研究

合成6个硒功能化杯芳烃为载体,采用双层夹心膜电位法直接测定了溶剂聚合物膜中载体与金属离子生成的络合物生成常数。制备并考察了以硒功能化杯芳烃为载体的银离子选择性电极的性能,发现以载体6为银离子选择性电子的载体,制成的膜电极,用作Ag^ 电位滴定Cl^-的指示电极,效果最佳。     

反相高效液相色谱法测定叶酸及其相关物质

建立了反相高效液相色谱法对叶酸及其相关物质的分离测定方法。对叶酸原料药进行了测定,色谱柱为JASCO C18柱(250mm×4.6mmi.d.,5μm),流动相为V(0.05mol LKH2PO4):V(0.1mol LKOH)∶V(甲醇)=78∶2∶20,流速为1.0mL min,柱温为30℃。叶酸检出限为1.0ng,叶酸的质量分数为98.52%～99 87%;加标回收率为95.22%～100.83%。该法快速简捷,精密度高,重现性好,可用于叶酸的质量控制。     

氨甲苯酸的荷移分光光度法测定

研究了氨甲苯酸与2,3 二氯 5,6 二氰 1,4 对苯醌的荷移反应。结果表明:在水介质中,两者于30℃水浴中恒温130min,可形成稳定的络合物,其λmax=340nm,线性范围1～9μg mL,相关系数r=0.9990,表观摩尔吸光系数ε=1.1×104L·mol-1·cm-1,方法的回收率99.93%～100.1%,相对标准偏差为0.72%～1.1%。用该方法测定了氨甲苯酸注射液,结果与文献方法一致。     

Predicting Dinitrogen Activation via Transition-Metal-Involved [4+2] Cycloaddition Reaction

As the strongest triple bond in nature, the N≡N triple bond activation has always been a challenging project in chemistry. On the other hand, since the award of the Nobel Prize in Chemistry in 1950, the Diels-Alder reaction has served as a powerful and widely applied tool in the synthesis of natural products and new materials. However, the application of the Diels-Alder reaction to dinitrogen activation remains less developed. Here we first demonstrate that a transition-metal-involved [4+2] Diels-Alder cycloaddition reaction could be used to activate dinitrogen without an additional reductant by density functional theory calculations. Further study reveals that such a dinitrogen activation by 1-metalla-1,3-dienes screened out from a series of transition metal complexes (38 species) according to the effects of metal center, ligand, and substituents can become favorable both thermodynamically (with an exergonicity of 28.2 kcal mol⁻¹) and kinetically (with an activation energy as low as 13.8 kcal mol⁻¹). Our findings highlight an important application of the Diels-Alder reaction in dinitrogen activation, inviting experimental chemists’ verification.     

Design and Construction of 3D Porous Na3V2(PO4)3/C as High Performance Cathode for Sodium Ion Batteries

An easy and delicate approach using cheap carbon source as conductive materials to construct 3D sequential porous structural Na3V2(PO4)3/C(NVP/C)with high performance for cathode materials of sodium ion battery is highly desired.In this paper,the NVP/C with 3D sequential porous structure is constructed by a delicate approach named as“cooking porridge”including evaporation and calcination stages.Especially,during evaporation,the viscosity of NVP/C precursor is optimized by controlling the adding quantity of citric acid,thus leading to a 3D sequential porous structure with a high specific surface area.Furthermore,the NVP/C with a 3D sequential porous structure enables the electrolyte to interior easily,providing more active sites for redox reaction and shortening the diffusion path of electron and sodium ion.Therefore,benefited from its unique structure,as cathode material of sodium ion batteries,the 3D sequential porous structural NVP/C exhibits high specific capacities(115.7,88.9 and 74.4 mA·h/g at current rates of 1,20 and 50 C,respectively)and excellent cycling stability(107.5 and 80.4 mA·h/g are remained at a current density of 1 C after 500 cycles and at a current density of 20 C after 2200 cycles,respectively).     

Theoretical computation of interaction parameters for the complexation of GSH with Pr(III) and Mg(II) in solution: Analysis of their reaction dynamics and thermodynamic characters

The current research focuses on the computation of absorption spectral parameters like energy interaction parameters viz. Slater-Condon factor (F_k), Racah (E^k), Lande spin-orbit interaction (ζ_4f), nephelauxetic ratio (β), bonding parameter (b^1/2), per cent covalency (δ), and the intensity parameters like oscillator strength (P) and Judd-Ofelt T_λ, (λ ​= ​2,4,6) parameters, of Pr³⁺ ion complexes with reduced Glutathione (GSH) in the presence and absence of Mg²⁺ in different aqueous solutions of CH₃OH, C₄H₈O₂, CH₃CN and DMF. The variations in the values of the energy interaction and intensity parameters clearly demonstrates the relative sensitivity of the 4f-4f transitions and its correlation with ligand structure and the nature of metal-ligand interaction. Further, the reaction dynamics and thermodynamic properties for the complexation of Pr³⁺ with glutathione and Mg²⁺ ligand have been investigated using different computed parameters like rate constant (k), activation energy (E_a), A (pre-exponential factor) and thermodynamic parameters, ΔH⁰, ΔG⁰ and ΔS⁰.     

The Physico-Chemical Properties of Glipizide: New Findings

The present work is a concrete example of how physico-chemical studies, if performed in depth, are crucial to understand the behavior of pharmaceutical solids and constitute a solid basis for the control of the reproducibility of the industrial batches. In particular, a deep study of the thermal behavior of glipizide, a hypoglycemic drug, was carried out with the aim of clarifying whether the recognition of its polymorphic forms can really be done on the basis of the endothermic peak that the literature studies attribute to the melting of the compound. A number of analytical techniques were used: thermal techniques (DSC, TGA), X-ray powder diffraction (XRPD), FT-IR spectroscopy and scanning electron microscopy (SEM). Great attention was paid to the experimental design and to the interpretation of the combined results obtained by all these techniques. We proved that the attribution of the endothermic peak shown by glipizide to its melting was actually wrong. The DSC peak is no doubt triggered by a decomposition process that involves gas evolution (cyclohexanamine and carbon dioxide) and formation of 5-methyl-N-[2-(4-sulphamoylphenyl) ethyl] pyrazine-2-carboxamide, which remains as decomposition residue. Thermal treatments properly designed and the combined use of DSC with FT-IR and XRPD led to identifying a new polymorphic form of 5-methyl-N-[2-(4-sulphamoylphenyl) ethyl] pyrazine-2-carboxamide, which is obtained by crystallization from the melt. Hence, our results put into evidence that the check of the polymorphic form of glipizide cannot be based on the temperature values of the DSC peak, since such a peak is due to a decomposition process whose Tonset value is strongly affected by the particle size. Kinetic studies of the decomposition process show the high stability of solid glipizide at room temperature.