Separation of 4C-Substituted Pyrrolidin-2-One Derivatives on Amylose-Based Chiral Stationary Phases

Chromatographia - Our previous studies concerning the enantioseparation of 4C-substituted pyrrolidin-2-one derivatives on coated polysaccharide-based chiral stationary phases have shown that...     

Natural‐Antioxidant‐Inspired Benzo[b]selenophenes: Synthesis,Redox Properties,and Antiproliferative Activity

The cyclization of arylalkynes under selenobromination conditions, combined with an acid‐induced 3,2‐aryl shift, was elaborated as a general synthetic pathway for the preparation of polyhydroxy‐2‐ and ‐3‐arylbenzo[b]selenophenes from the same starting materials. The redox properties, free‐radical‐scavenging ability, and cytotoxicity against malignant cell lines (MCF‐7, MDA‐MB‐231, HepG2, and 4T1) of the synthesized compounds were explored, and the obtained results were used to consider the structure–activity relationships (SARs) in these compounds. Consequently, the structural features that were responsible for the highly potent peroxyl‐radical‐scavenging activity were established.     

Synthesis and self-assembly of novel fluorous cationic amphiphiles with a 3,4-dihydro-2(1H)-pyridone spacer

The synthesis of fluorous (highly fluorinated) 3,4-dihydro-2(1H)-pyridone-5-carboxylate cationic amphiphiles have been described, where the dihydropyridone serves as a spacer and either a pyridinium bromide or a triphenylphosphonium bromide form the polar cationic head group. The in water self-assembled aggregates have been observed by atomic force microscopy (AFM) and dynamic light scattering (DLS).     

Aspects of Periodate Oxidation of Carbohydrates for the Analysis of Pyrolysis Liquids

Periodate oxidation of carbohydrates in acid, neutral, and alkaline media has been studied in order to develop a simple and fast determination method of sugars and their derivatives, such as levoglucosan, in fast pyrolysis liquids. The carbohydrates oxidized are as follows: D-glucose, D-cellobiose, D-cellotriose, D-fructose, D-sucrose, and levoglucosan. The reaction products have been analyzed with two methods: iodometric titration for iodate ions and potentiometric titration for formic acid.     

Enantioseparation of 4C-Substituted Pyrrolidin-2-One Derivatives on Polysaccharide and Macrocyclic Glycopeptide Chiral Stationary Phases

Chromatographia - To extend our previous studies concerning the enantioseparation of 4C-substituted pyrrolidin-2-one derivatives on polysaccharide-based chiral stationary phases with...     

Determination of phosphoric acid triesters in human plasma using solid-phase microextraction and gas chromatography coupled to inductively coupled plasma mass spectrometry

A simple and sensitive method for determination of phosphoric acid triesters at trace levels in human plasma sample is described. In this work, solid-phase microextraction (SPME) is employed as a sample preparation procedure for extraction and pre-concentration of alkyl and aryl phosphates followed by gas chromatography coupled to inductively coupled plasma mass spectrometry (GC-ICP-MS) for phosphorus-specific and very sensitive determination of these compounds in human plasma. The detection limits from blood plasma were 50 ngL(-1) (tripropyl phosphate), 17 ngL(-1) (tributyl phosphate), 240 ngL(-1) (tris(2-chloroethyl) phosphate) and 24 ngL(-1) (triphenyl phosphate). Sample preparation involves plasma deproteinization followed by direct immersion SPME with 65 microm poly(dimethylsiloxane/divinylbenzene) fiber. Extraction was performed at 40 degrees C for 30 min and at pH 7.0 in 10 mM sodium carbonate buffer. The reported method, to our knowledge, describes the first application of SPME with element-specific detection for analysis of phosphoric acid esters. Application of the method to the plasma samples, previously stored in poly(vinyl chloride) plasma bags revealed the presence of triphenyl phosphate, which was further confirmed by SPME GC time-of-flight high-resolution mass spectrometry.