The methanol hemisolvate of amiloride hydrochloride

In the asymmetric unit of N-(3,5-di­amino-6-chloro­pyrazin-2-yl­carbonyl)-N-(di­amino­methyl­ene)­ammonium chloride methanol hemisolvate, C₆H₉ClN₇O⁺·Cl⁻·0.5CH₄O, there are two crystallographically different amiloride mol­ecules. Crystallographically identical amiloride mol­ecules are stacked one above the other, alternately rotated by 180°. These stacks are arranged parallel to each other, forming layer A. The least-squares plane of the non-H atoms of the other mol­ecules lying in layer B is tilted against the corresponding plane of the mol­ecules in layer A by an angle of 79.89 (3)°. The methanol mol­ecules and Cl⁻ anions are located between these layers, although the methanol mol­ecules are closer to layer A.     

α‐Onocerin chloro­form hemisolvate

The triterpenoid natural product α‐onocerin [8,14‐secogammacera‐8(26),14(27)‐diene‐3,21‐diol], determined here as the chloro­form hemisolvate, C₃₀H₅₀O₂·0.5CHCl₃, consists of two independent symmetric trans‐decalin C₁₅ building blocks. Hydro­gen bonds between the hydroxyl groups form an infinite two‐dimensional network perpendicular to the c axis.     

雌二醇的流动注射阻抑化学发光法测定

基于碱性介质中雌二醇对N-溴代丁二酰亚胺-钙黄绿素化学发光体系的阻抑作用,建立了雌二醇的流动注射化学发光分析新方法,优化了其分析条件,并初步探讨了该化学发光反应的机理。该方法测定雌二醇的线性范围为0.02~0.1、0.1~8.0 mg/L,检出限为0.008 5 mg/L。对0.1 mg/L的雌二醇标准溶液进行11次平行测定,相对标准偏差为1.2%。将该法用于注射液中雌二醇的测定,结果满意。     

Chlorotris(2,4,6‐trimethylphenyl)tin(IV) and its ethanol hemisolvate

Chloro­tris(2,4,6‐tri­methyl­phenyl)­tin(IV), crystallizes from ethanol as solvent‐free needles, [Sn(C₉H₁₁)₃Cl], (I), and as the hemisolvate, [Sn(C₉H₁₁)₃Cl]·0.5C₂H₆O, (II). The asymmetric unit in (I) has three independent mol­ecules, whereas in (II), there are two [Sn(C₉H₁₁)₃Cl] mol­ecules together with one ethanol molecule. In the unit cell of (II), the ethanol mol­ecules lie in channels between stacks of (Mes)₃SnCl mol­ecules (Mes is 2,4,6‐tri­methyl­phenyl) and each ethanol mol­ecule is disordered (0.50:0.50) over two positions. A comparison of the structures of the title compounds and other (Mes)₃SnX (X = F, Br or I) systems with those of the tri­phenyl­tin analogues shows that the steric requirements of the o‐CH₃ groups are met by a flattening of the SnC₃ skeleton and increases in the average Sn—X and Sn—C values. Comparing Sn—X data for (Mes)₃SnX (X = F, Cl, Br or I) systems with values for the tris(o‐methoxy­phenyl)­tin analogues suggests that the Sn—F distance of 1.961 Å in (Mes)₃SnF may well be characteristic of sterically unhindered four‐coordinate Ar₃SnF systems.     

Lagoden dimethylformamide hemisolvate dihydrate: absolute configuration,dipolar interactions and hydrogen‐bonding interactions

Lagoden (L·3H₂O, where L is Na⁺·C₂₀H₃₃O₆⁻; sodium 3β,16,18‐trihydroxy‐8,13‐epi‐9,13‐epoxylabdan‐15‐oate trihydrate) is widely used as an effective haemostatic agent. It has been crystallized from dimethylformamide (DMF) as sodium 3β,16,18‐trihydroxy‐8,13‐epi‐9,13‐epoxylabdan‐15‐oate dimethylformamide hemisolvate dihydrate, Na⁺·C₂₀H₃₃O₆⁻·0.5C₃H₇NO·2H₂O or L₂·DMF·4H₂O, and the asymmetric unit contains two of the latter formulation. The four symmetry‐independent Na⁺ cations and lagoden anions, one DMF molecule and six of the eight symmetry‐independent water molecules assemble into a one‐dimensional polymeric structure via dipolar and hydrogen‐bonding interactions. The lagoden anions coordinate to the Na⁺ cations via the carboxylate groups and the two primary hydroxy groups, whereas the secondary OH groups are solely involved in hydrogen bonding. Two of the four symmetry‐independent lagoden anions act in a chelating mode, forming seven‐membered chelate rings. The absolute structure, based on anomalous dispersion data collected at 130 K with Cu Kα radiation, confirms an inverted configuration at chiral centres C8 and C13 (labdane numbering) relative to the labdane skeleton.     

Synthesis and Investigation of Estradiol Receptors Modulators

New modulators of estradiol receptors were synthesized, 17(-alkoxy-3-oxo-8-isoestr-5(10)-enes and the respective D-homoanalogs. Reaction of these compounds with CuBr₂ in acetonitrile furnished steroids with aromatic A ring possessing hypocholesterolemic and osteoprotective activity.     

HPLC-ESI-TOFMS检测尿液中的雌二醇

用HPLC—ESI-TOFMS建立了快速灵敏检测尿中雌二醇的方法,尿样中雌二醇经盐酸水解后用OASISHLB小柱萃取．色谱柱为XTerraMS C18反相分离柱（3．5μm,2．1mm×100mm）,流动相为水和乙腈,梯度洗脱,流速为0．2mL／min,紫外检测波长为280nm,外标法定量．质谱采用负离子电离模式．线性方程：y=1．79×10^5x＋2．59×10^4,线性范围：0．0328—32．8mg／L,线性相关系数R^2=0．9979,最小检出浓度0．00328mg／L,萃取回收率101．83％．应用本方法对10例正常人尿样进行测定,结果满意．相比较其它检测尿中雌二醇的方法来说,此法比较简单、快速、准确,为临床的诊断提供有价值的指标．     

时间分辨荧光免疫分析法间接测定雌二醇

以氯磺酰基噻吩甲酰三氟丙酮（CTTA）为铕（Eu)的螯合剂,羊抗鼠（SAM）的IgG为二抗,用SAM－IgG-CTTA-Eu作标记二抗,建立了以竞争抑制为基础的时间分辨荧光免疫分析测定离雌二醇（E2）的新方法。同均相方法相比灵敏度有很大提高,测定雌二醇（E2）的线性范围为2．5－200pg/mL,检测限为2.5pg/mL。这一方法可望用于E2的临床检测。     

Chromatographic Behaviour and Lipophilicity of Estradiol Derivatives

The retention behaviour of estradiol derivatives has been studied by HPLC on polar chemically bonded stationary phases: C₃CN, DIOL and C₃NH₂, commercially available columns. The mobile phases used were: methanol-water and acetonitrile-water in various proportions. Reversed-phase chromatography occurred on polar chemically bonded stationary phases. Correlation between the retention constants of estradiol derivatives obtained on polar chemically bonded phases and log P calculated via different methods was examined too.     

时间分辨荧光免疫分析法直接测定雌二醇

合成了雌二醇抗原,并获得了雌二醇单克隆抗体,通过酶联免疫吸附法测得效价为１．０×１０＾７。使用洗脱增强－时间分辨荧光免疫分析法测定了血清中的雌二醇,浓度范围为１．０×１０＾－２－１．０×１０＾３μｇ／Ｌ,最低检出限为５．６ｎｇ／Ｌ,批内ＲＳＤ％小于３．７％,批间ＲＳＤ％小于７．５％。将测定结果 放射免疫分析法作了比较。     

The negative ion mass spectra of methanol and deuterated methanol

The negative ion mass spectra of methanol, methanol-d and trideuteromethanol have been measured at 70 eV. Use of deuterated methanols has enabled the ion at m/e 31 to be identified as CH₃O^? and not CH₂OH^?. Isotope effects have been determined for H^? and D^? formation, and for OH^? and OD^? formation. It has been shown that OH^? formation occurs as a rearrangement reaction as well as by simple C? O bond fission.     

Simultaneous Analysis Of Estradiol Dienanthate,Estradiol 3-Benzoate And Testosterone Enanthate Benzilic Acid Hydrazone In Oily Formulations Bygradient-Hplc

Abstract

A procedure is described for the analysis of estradiol-3-benzoate, testosterone enanthate benzylic acid hydrazone and estradiol dienanthate in oily solution. The multi-step gradient reversed phase ion-pairing HPLC method uses 1-pentane sulfonic acid sodium salt (0.0025 M in 0.1% acetic acid methanolic solution): acetonitrile and water (55 : 30 to 45 : 15 to 0) mobile phase gradient and a 250 × 4.6 mm, 5 micron octadecyl silane column, with 1,2,4,5-tetrachlorobenzene as internal standard. The time required for chromatography is 31 minutes. The method gives relative standard deviations (RSD) of .94% or better for the assay of active ingredients in commercial formulations.     

Recent development of methanol electrooxidation catalysts for direct methanol fuel cell

Direct methanol fuel cells(DMFCs) are very promising power source for stationary and portable miniature electric appliances due to its high efficiency and low emissions of pollutants. As the key material, catalysts for both cathode and anode face several problems which hinder the commercialization of DMFCs.In this review, we mainly focus on anode catalysts of DMFCs. The process and mechanism of methanol electrooxidation on Pt and Pt-based catalysts in acidic medium have been introduced. The influences of size effect and morphology on electrocatalytic activity are discussed though whether there is a size effect in MOR catalyst is under debate. Besides, the non Pt catalysts are also listed to emphasize though Pt is still deemed as the indispensable element in anode catalyst of DMFCs in acidic medium. Different catalyst systems are compared to illustrate the level of research at present. Some debates need to be verified with experimental evidences.     

基于甲醇自由基还原波的甲醇极谱测定

利用过硫酸根在电极上还原产生的硫酸根自由基SO4· - 将甲醇氧化成甲醇自由基HC·HOH ,该自由基还原产生极谱还原波 ,拟定了极谱测定甲醇的新方法。在 0 .0 33mol/LKH2 PO4+Na2 HPO4(pH 6.1± 0 .1 ) + 1 .6× 1 0 - 2 mol/LK2 S2 O8介质中 ,甲醇自由基还原波峰电流与甲醇浓度在 3.1 5× 1 0 - 4 mol/L～ 9 46× 1 0 - 3mol/L范围呈线性关系。用该方法测定了甲醇生产车间空气中的甲醇含量     

Crystal Structures and Physicochemical Properties of Solvated Estradiol

Polymorph screening is currently one of the most important tasks for innovators and for generic companies from both pharmaceutical and intellectual property rights aspects. The hemihydrate form(Form Ⅰ) and formamide solvate(Form Ⅱ) of estradiol are isolated and prepared via systemic crystallization screening in this paper, and the formamide solvate form is reported for the first time. Both polymorphic forms were characterized by single-crystal X-ray structure analysis(SXRD), powder X-ray diffraction(PXRD), and thermal analysis(TGA and DSC). The PXRD experiments indicate that the samples in this study are the pure polymorphic forms via comparing the patterns with the simulated ones. The stability and equilibrium solubility data of the solid-state phase were also examined in order to check the impact of the differences observed in their crystalline structures. It has been found that Forms I and II are of conformational polymorph and Form II is the more thermodynamically stable solid form, while Form I possesses higher solubility, indicating its possibility as an alternate solid form for its further solid formulation development if necessary.     

基于温度敏感水凝胶的雌二醇荧光免疫分析

雌二醇完全抗原(Ag)与异丙基丙烯酰胺(NIPA)共聚,可得水凝胶－抗原结合物(pNIPA－Ag),pNI－PA-Ag与游离的雌二醇(E₂)竞争有限的荧光标记的单抗McAb-F,利用水凝胶温度相变的性质,分离高分子免疫复合物,并测定其荧光信号.结果表明,游离E₂在10～625ng/mL范围内呈线性关系,样品的回收率为88.9%～102.0%.     

Different Biotinylation Strategies for Competitive Immunoassay of Estradiol

Study on biotinylation strategies for competitive immunoassay of estradiol (E2) was carried out. Two types of competitive enzyme immunoassay (EIA) with Biotin-Avidin amplification system were established and optimized.The E2-Biotin conjugate was used as a tracer in one assay, and biotinylated antibody was used as a tracer in the other. In both of EIAs, horseradish peroxidase-labelled Avidin (Avidin-HRP) was used with a spectrometric determination of enzyme activity. The precision, sensitivity and specificity were measured and compared. The results showed that although both were satisfactory in specificity, the EIA with hapten-Biotin showed to be superior to the EIA with biotinylated antibody in sensitivity and precision. The limit of detection of serum E2 was 8 and 50 pg/mL with E2-Biotin and biotinylated antibody as tracer, respectively.     

μ-Bis(diphenylphosphino)methane-P:P′-octacarbonyldimanganese(Mn–Mn) and its toluene hemisolvate

The Mn—Mn bonds in the two independent mol­ecules of the unsolvated title compound, [Mn₂(C₂₅H₂₂P₂)(CO)₈], (I), are 2.9714 (7) and 2.9746 (7) Å. This bond is distinctly shortened in the toluene hemisolvate, [Mn₂­(C₂₅­H₂₂P₂)(CO)₈]·­0.5C₇H₈, (II), to 2.9338 (14) Å and this shortening is accompanied by an increase in magnitude of the P—Mn—Mn—P torsion angle [26.93 (3) and 28.44 (3)° in (I), and 33.25 (7)° in (II)], while the P⋯P `bite' is much less affected [3.092 (2) and 3.099 (2) Å in (I), and 3.091 (3) Å in (II)]. The toluene solvate mol­ecule in (II) lies on a twofold axis.