Rapid and simple determination of aldose reductase and sorbitol dehydrogenase

Rapid and well-reproducible methods were developed for the determination of aldose reductase and sorbitol dehydrogenase. The aldose reductase activity measurement is based on photometric o-toluidine aldose back-measurement, which is widely used in laboratories for the quantitative determination of glucose. The spectrophotometric method based on the quantitative decrease in NADH proved suitable for the measurement of sorbitol dehydrogenase activity.Both methods could well be employed for the measurement of the aldose reductase and sorbitol dehydrogenase activities of normal and diabetic tissue homogenizates, and for the comparison of the measured values.     

多孔碳球封装纳米碳化钼催化剂无溶剂催化苄胺偶联反应

以盐酸多巴胺，磷钼酸（PMo）为原料，通过离子交换和聚合作用形成一种有机-杂多酸杂化材料，在N₂条件下高温碳化制备出一种新型多孔碳球封装纳米碳化钼催化剂PDA-PMo-800.利用傅里叶变换红外（FT-IR），N₂吸脱附等温仪（BET），扫描电子显微镜（SEM），透射电子显微镜（TEM），X射线粉末衍射（XRD），拉曼光谱仪（Raman），热重分析仪（TG），能谱仪（EDS）对催化剂进行表征与分析.结果显示：催化剂PDA-PMo-800具有规整的花状球体形貌以及较高的比表面积（102 m²/g），纳米碳化钼颗粒（3~4 nm）均匀地分布在多孔碳球骨架内.在无溶剂以氧气为氧化剂的条件下，将该催化剂应用于苄胺的氧化偶联反应合成亚胺，实现较高的转化率及选择性，且催化剂可以多次重复使用并保持较高的催化活性.     

Determination of dioxopromethazine hydrochloride by capillary electrophoresis with electrochemiluminescence detection

The paper presents a rapid method for the determination of dioxopromethazine hydrochloride (DPZ), an antihistamine drug, by the capillary electrophoresis with electrochemiluminescene detection (CE–ECL) using tris(2,2′-bipyridyl)ruthenium(II) (Ru(bpy)₃²⁺) reagent. This CE–ECL detection method has high sensitivity, good selectivity and reproducibility for DPZ analysis. Under the optimized conditions: separation capillary, 38 cm length (25 μm i.d.); sample injection, 10 s at 8 kV; separation voltage, 12.5 kV; running buffer, 20 mmol L⁻¹ sodium phosphate of pH 6.0; detection potential, 1.15 V; 50 mmol L⁻¹ of phosphate buffer (pH 7.14) containing 5 mmol L⁻¹ of Ru(bpy)₃²⁺ in ECL detection cell, the detection limit of DPZ was 0.05 μmol L⁻¹ (S/N = 3). The linear range extended from 5 to 100 μmol L⁻¹. The linear curve obtained was Y = 181.62 + 9.28X with a correlation coefficient of 0.9970. The relative standard deviations of the ECL intensity and the migration time for six continuous injections of 5 μmol L⁻¹ DPZ were 3.7% and 0.92%, respectively. The CE–ECL method was applied to analyze DPZ in real samples including tablets, rat serum and human urine, and satisfactory results were obtained without interference from samples matrix. The CE–ECL technique was proved to be a potential method for the detection of DPZ in clinic analysis.     

Potentiometric flow injection analysis of dicyclomine hydrochloride in serum, urine and milk

Five plastic membrane electrodes for the determination of dicyclomine hydrochloride (DcCl) were fabricated and fully characterized in terms of composition, life span, usable pH range, working concentration range and temperature. The membranes of these electrodes consist of dicyclominium-silicotungstate (Dc-ST), silicomolybdate (Dc-SM), phosphotungstate (Dc-PT), phosphomolybdate (Dc-PM) or tetraphenylborate (Dc-TPB) ion-associations dispersed in PVC matrix with dibutyl phthalate plasticizer. The electrodes showed near-Nernstian response over the concentration range of 4.0 × 10⁻⁶ to 1.0 × 10⁻² M DcCl and applied to the potentiometric determination of dicyclominium ion in pharmaceutical preparations, serum, urine and milk in batch and flow injection (FI) conditions with average recoveries of 96.1-102.7% and relative standard deviation of 0.055-1.994%. The electrodes exhibit good selectivity for DcCl with respect to a large number of inorganic cations, organic cations, sugars and amino acids. The sensitivities of these electrodes are high enough to measure as low as 1.73 μg/ml of DcCl which permit the determination of the K_sp values of the ion-associates used. The proposed potentiometric methods offer the advantages of simplicity, accuracy, automation feasibility and applicability to turbid and colored sample solutions.     

Transformed steroids. 190. Influence of Co-complexation on the epoxide ring opening of 17β-ethynyl-16α,17α-epoxyandrost-4-en-3-one on reacting with pyridine hydrofluoride,pyridine hydrochloride,and pyridine thiocyanate

The epoxide ring opening of 16,17-epoxy-17-ethynylandrost-4-en-3-one and its dicobalt hexacarbonyl complex on reacting with Py·HF, Py·HCl, and Py·HSCN was studied. The results of these reactions and the structure of the end products depend not only on the complexation of the acetylene bond, but also on the nucleophilic reagent used. On the basis of the reaction of a Co-coordinated 16,17-epoxy-17-ethynylandrost-4-en-3-one there has been developed a preparative method for the synthesis of pregn-4-ene-3,20-dione-[17,16-d]-1,3-oxazolidin-2-one.N. D. Zelinskii Institute of Organic Chemistry, Russian Academy of Sciences, 117913 Moscow. Translated fromIzvestiya Akademii Nauk, Seriya Khimicheskaya, No. 11, pp. 2661–2666, November, 1992.     

相转移催化二苯美仑类化合物的合成

以苯甲醇、苯酚为起始原料,在催化剂活性Al2O3存在下,通过Claisen重排反应得到关键中间体2-苄基苯酚,利用相转移催化技术进行醚化反应后,再经过胺化、酸化反应合成得到一种新型结构的二苯美仑类化合物。反应过程经优化使中间体2-苄基苯酚产率较文献提高8%,反应总收率64.7%。合成产物化学结构经红外光谱、核磁共振、质谱、元素分析得到确证。     

Spectrophotometric Determination of Ondansetron Hydrochloride in Pharmaceutical Bulk and Dosage Forms

A rapid, simple and accurate spectrophotometric method is developed for the determination of ondansetron hydrochloride in pure and tablet formulations. The method depends on the charge‐transfer complexation between ondansetron base as n‐electron donor with chloranil as π‐acceptor to give a colored complex, which absorbs maximally at 470 nm. Beer's law is obeyed in the concentration ranges 70–980 μg mL^?1 with molar absorptivity of 4.47 × 10² L mole^?1 cm^?1. The proposed method is precise, accurate and specific for the quantitative determination of drug in bulk and tablet formulations.     

维生素B1—金属配合物的制备及其分子结构

制得了M(th)Cl_3 (M=Zn(Ⅱ)、Cd(Ⅱ)、Mn(Ⅱ)、Co(Ⅱ))、Cu(thH)Cl_4和Hg_3(C_(12)H_(16)N_4OS)Cl_8三种类型的维生素B_1-金属配合物。结构表征表明,Zn、Cd、Mn、Co配合物属M—N配位型,Cu配合物属离子型,Hg配合物既有M—O键合,又有离子键存在。     

Ion Pairing,H‐bonding,and π‐π Interactions in Cobalt(II) Compound Containing Guanidinium Counter Ion

A novel proton transfer compound, (GH)₂(phendc), ( 1 ), was synthesized from the reaction of 1,10‐phenanthroline‐2,9‐dicarboxylic acid, phendcH₂, and guanidine hydrochloride, (GH)(Cl), (G: guanidine). The characterization was performed using IR, ¹H and ¹³C NMR spectroscopy. The cobalt(II) compounds were synthesized using proton transfer compounds containing guanidinium counter ion. These proton transfer compounds are (GH)₂(phendc), and (GH)₂(pydc) (pydcH₂: 2,6‐pyridinedicarboxylic acid). The chemical formulae and space groups are (GH)₂[Co(phendc)₂]·4H₂O, (2) , and (GH)₂[Co(H₂O)₆][Co(pydc)₂]₂, P2₁/n (3) . Non‐covalent interactions such as ionpairing, hydrogen bonding and π‐π stacking are discussed.     

Enantiomeric Resolution on L—Carnitine Selective Polymers Prepared by Molecular Imprinting

L-carnitine selective polymers were prepared by molecular imprinting using methacrylic acid as the functional monomer. The acid function of the monomer is expected to form hydrogen bond and ionic interactions with the amine function of the target molecule L-carnitine.The imprinted polymers were used as stationary phases in high-performance liquid chromatography (HPLC). It was shown that L-carnitine imprinted polymer exhibited a higher affinity to its template molecule,while the non-imprinted polymer had no affinity to the compounds tested. Racemic carnitine hydrochloride was efficiently resolved on the L-carnitine imprinted polymer, and the separation factor is 1.9.