Investigations of 2,3′-biquinolyl. 8. Reduction of 1-alkyl-3-(2-quinolyl)-quinolinium halides with sodium borohydride

Reduction of 1-alkyl-3-(2-quinolyl)quinolinium halides with sodium borohydride leads to 1-alkyl-1,2-dihydro-2,3-biquinolyls which, except for the ethoxycarbonyl derivative, undergo rearrangement to 1-alkyl-1,4-dihydro-2,3-biquinolyls. The last can be synthesized by the alkylation of the corresponding 1,4-dihydro-2,3-biquinolyls under conditions of interphase catalysis and in the system KOH-DMSO.For Communication 7, see [1].Stavropol' State University, Stavropol' 355009, Russia; nauka@stavsu.ru. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1084–1087, August, 2000.     

高效液相色谱法测定舒普深中的舒巴坦钠和头孢哌酮钠

 应用反相高效液相色谱外标定量法同时测定了舒普深中的舒巴坦钠和头孢哌酮钠。采用 pH 4 0的磷酸水溶液 乙腈 (体积比为 80∶2 0 )组成的流动相 ,在ODS柱上 ,于 12min内同时测定舒巴坦钠和头孢哌酮钠。方法简单 ,重现性好 ,在线性范围内舒巴坦钠的相关系数为 0 9997(n =5 ) ,头孢哌酮钠的相关系数为 0 9991(n=5 )。方法适于对药品舒普深的生产过程及临床上该药的血药浓度的监测。     

The Influence of Addition of Inorganic Carbonates on the Relative Volatility Factor of Light and Heavy Water at Temperatures Close to the Isotope Effect Inversion Temperature

The influence of Na₂, CO₃, K₂CO₃, and Li₂CO₃ addition on the relative volatility factor α of light and heavy water ai temperatures close to the isotope effect inversion temperature has been investigated. The measurements for Na₂CO₃ and K₂CO₃ solutions have been made in the temperature range. 100–330 °C at various salt concentrations. In the case of Li₂CO₃ temperature range and concentration was limited by the solubility of this salt. The factor α was determined by analysis of gas and liquid phases at equilibrium. Data on pure waters obtained by other investigators are listed for comparison. The temperature dependence of factor α for salt solutions and pure waters is presented in the form of equations derived from experimental data.     

The 24Na Induced Activity as a Neutron Dosimeter for Radiobiologial Experiments

Measurement of the ²⁴Na induced activity as a part of a dosimetric system for radiobiological experiments was found to be an approach characterized by its proper reliability, reproducibility (relative error less than 8-5%) and high sensitivity (activities of about 0-01 μCi may be detected).     

NaIO4/LiBr‐Mediated Direct Conversion of Benzylic Alcohols and Aromatic Aldehydes to Aromatic Esters

Aromatic aldehydes or benzylic alcohols are directly converted to the corresponding aromatic esters in high yields on treatment with methanol or ethanol mediated by sodium metaperiodate (NaIO₄)/LiBr in an acidic medium.     

A method for the analysis of sucralose with electrospray LC/MS in recipient waters and in sewage effluent subjected to tertiary treatment technologies

A method for the analysis of the artificial sweetener sucralose in sewage water and recipient water was developed. Extraction and clean up was performed with solid-phase extraction utilising Oasis HLB columns. Detection was made by liquid chromatography electrospray mass spectrometry (LC/MS). The triple-quadrupole mass spectrometer was operated in multiple reaction monitoring (MRM) mode. However, ‘pseudo MRM’ was used, a technique where the two quadrupoles monitor the same m/z. The sodium adduct of sucralose was used for quantification, since lower detection limits were obtained as compared to the sucralose quasi-molecular ion in negative ion mode. The two ions with highest intensity in the chlorine isotope pattern were monitored. The reduction of matrix effects with this approach is discussed. The method limit of quantification (MLOQ) for sewage water was 0.2?µg?L^?1, whereas for recipient water MLOQ was 0.02?µg?L^?1. The method was used to analyse effluent samples from an experimental sewage treatment plant (STP) to assess the efficiency of tertiary treatment techniques for removal of sucralose. Filtration through activated carbon was shown to be efficient, while ozonation, advanced oxidation techniques and membrane bioreactors were less efficient. Analyses of receiving waters showed low dilution of sucralose emitted from the STPs.     

Comparison of Some Soft Unplasticized Cast Polyurethane Rubbers

Different types of unplasticized cast polyurethanes with hardness around 60 Shore A have been compared. The tensile properties, tear strength, resistance to hydrolysis, and swelling in solvents and water were examined. The influence of composition on the properties of cast polyurethanes prepared from a polyadipate polyol and diisocyanates, including the effect of a range of fillers, was investigated in detail. Fumed silica, fumed alumina, and carbon black significantly increased the hardness and tensile strength of the rubber, whereas kaolin and talc gave small increases. Ground silica, calcite, and rutile had no effect. No significant increases in tensile strength were obtained with silane and titanate coupling agents with a fumed silica filler. The rate of hydrolysis or extent of swelling in xylene was unchanged by fillers.     

Raney Nickel–Catalyzed Hydrogenation of Unsaturated Carboxylic Acids with Sodium Borohydride in Water

A mild, selective, and green method for the reduction of unsaturated carboxylic acids with sodium borohydride–Raney nickel (W6) system in water is reported. This method is practical and safe and avoids use of organic solvents.