Measurement of polyunsaturated fatty acids of myocardial lipids by high performance liquid chromatography

Summary This report describes a modified method for the separation and analysis of polyunsaturated fatty acids such as 20:4, 20:5, and 22:6, using HPLC. The results show that these fatty acids are well separated from the saturated acids. Since the unsaturated fatty acids elute earlier than saturated acids, and this method does not require the fractionation of free fatty acids using thin layer chromatography, a necessary step for the gas chromatographic analysis, the recoveries of polyunsaturated fatty acids were significantly higher as compared to those from gas chromatography. Furthermore, HPLC and gas chromatographic methods gave identical results for the acyl chain composition of phosphatidylserine. The advantages of using HPLC over gas chromatography in determining the acyl chain composition of free fatty acids and phospholipids are also discussed.     

Studies in spiroheterocycles. Part XIII. Synthesis of a novel spiro system: Spiro[9H-acridine-9,3′-[3h]indol]-2′(1′H)-one and related compounds from new fluorinated spiro[3H-indole-3,9′-[9H]xanthen]-2(1H)-ones

A new spiroheterocyclic system spiro[9H-acridine-9,3′-[3H]indol]-2′(1′H)-one and related compounds have been prepared by the reaction of spiro[3H-indole-3,9′-[9H]xanthen]-2(1H)-ones with aromatic amine or ammonium acetate. The latter were prepared by heating fluorinated indole-2,3-diones with m-/p-cresols or α-naphthol in the presence of sulphuric acid at 230-240°. The synthesized compounds have been characterized on the basis of their elemental analyses, ir, nmr (1_H, 13_C, 19_F) and mass spectral data.     

Electron donor properties and catalytic activity of manganese ferrospinels

The electron donating properties of manganese ferrospinels of various compositions (MnFe₂O₄, Mn_1.2Fe_1.8O₄, Mn₂FeO₄ and Mn_2.5Fe_0.5O₄) were studied from the adsorption of electron acceptors of various electron affinity values from acetonitrile as solvent. The limit of electron transfer from the oxide surface is from 1.77 to 2.40 eV in terms of the electron affinity of the electron acceptor. The data have been correlated with the catalytic activity of these oxides towards autoxidation of sulfites. Both weak and strong electron donor sites catalyze the reaction.     

Seasonal variation of uranium and physico-chemical parameters in spring water sources of Pithoragarh city,Uttarakhand, India

Journal of Radioanalytical and Nuclear Chemistry - The paper deals with the seasonal variation of physico-chemical parameters in natural spring water sources collected from Pithoragarh city,...     

Simultaneous recovery of plutonium and americium from assorted analytical waste solutions using extraction chromatography

A rapid extraction chromatography based methodology was developed for simultaneous recovery of plutonium and americium from various kinds of analytical waste obtained during chemical quality control of plutonium based nuclear materials using sulphonic acid based actinide? resin. Efforts were made to understand the effect of initial feed acidity, gamma radiation and the concentrations of Am³⁺ and Pu⁴⁺ on their k _d. values. Processing of assorted analytical waste solutions through this method revealed that more than 95 % of Am³⁺ and 90 % of Pu⁴⁺ were adsorbed on the resin while iso- propanol can be successfully employed for the quantitative recovery of both the actinides from the loaded resin phase.     

Catalysis of Ethanol Decomposition over Rare Earth Oxide Supported Vanadia

Supported vanadia systems synthesized by the excess solvent technique were characterized by different analytical methods. The selective oxidation activity of the system was examined towards the decomposition of ethanol.     

A new diastereoselective intramolecular electroreductive coupling of unsaturated β-ketoesters and β-ketoamides in ionic liquids at a tin cathode

The diastereoselective intramolecular electroreductive coupling of several β-ketoesters and β-ketoamides has been accomplished at a tin cathode in ionic liquids and isopropanol (9:1). The ionic liquids used are 1-butyl-3-methylimidazolium bromide [BMIM]Br, 1-butyl-3-methylimidazolium tetrafluoroborate [BMIM]BF₄, 1-methoxyethyl-3-methylimidazolium trifluoroacetate [MOEMIM]CF₃COO and 1-methoxyethyl-3-methylimidazolium mesylate [MOEMIM]Ms. This methodology offers a clean and green process for the synthesis of functionalized carbocycles in good yields with excellent stereochemical control at three stereogenic centres.