Chromatographic procedures were developed and successfully employed for the separation of a high number of organic and inorganic compounds present at trace level in complicated accompanying matrices. The capacity of chromatographic separation technologies can be increased by the modification of both the stationary and the mobile phase of the system. Because of their specific adsorption characte...

Chromatographic procedures were developed and successfully employed for the separation of a high number of organic and inorganic compounds present at trace level in complicated accompanying matrices. The capacity of chromatographic separation technologies can be increased by the modification of both the stationary and the mobile phase of the system. Because of their specific adsorption characte...

A stereoselective high performance liquid chromatography method has been developed for the chiral separation of the enantiomers of six antihistamines, doxylamine, carbinoxamine, dioxopromethazine, oxomemazine, cetirizine and hydroxyzine. The effects of mobile phase additive, column temperature and flow rate on the retention time and resolution were studied. Enantiomeric separation of cetirizine...

Amphiphilic 2,6-pyridylene ethynylene "meta-ethynylpyridine" polymers having chiral oligo(oxyethylene) side chains were developed as hosts for saccharide recognition. The polymers were prepared via a Sonogashira reaction and fractionated by gel permeation chromatography (GPC). They showed circular dichroism (CD) activity due to their higher-order chiral helical structures, and their CD and UV-v...

A variety of chiral N-phosphinyl α-imino esters have been synthesized for the first time from ketoesters and phosphinylamide, which were then reduced by L-selectride to give the corresponding N-phosphinyl-protected α-amino esters. The reduction proceeded very well with excellent chemical yields (88-98%) as well as high diastereoselectivities (96:4 to 99:1). Some of these products could be obtai...

The hydro-chloride salt of chiral l-nebivolol {systematic name: (+)-(R,S,S,S)-bis-[2-(6-fluoro-3,4-dihydro-2H-1-benzopyran-2-yl)-2-hydroxy-ethyl]ammonium chloride dihydrate}, C(22)H(26)F(2)NO(4) (+)·Cl(-)·2H(2)O, was obtained by chiral liquid chromatography as a dihydrate. The pyran rings adopt half-chair conformations. Hydrogen bonds between the cation, anions and water mol-ecules contribute t...

Helical structures are chiral, which means that if we can synthesize a polymer having a stable one-handed helicity, the polymer is optically active. In 1979, we succeeded in the synthesis of a one-handed helical polymer from an optically inactive achiral monomer, triphenylmethyl methacrylate (TrMA). This is the first example of the asymmetric synthesis of an optically active one-handed helical ...

Core-shell silica microspheres with a nanocellulose derivative in the hybrid shell were successfully prepared as a chiral stationary phase by a layer-by-layer self-assembly method. The hybrid shell assembled on the silica core was formed using a surfactant as template by the copolymerization reaction of tetraethyl orthosilicate and the nanocellulose derivative bearing triethoxysilyl and 3,5-dim...

Many substances of forensic interest are chiral and available either as racemates or pure enantiomers. Application of chiral analysis in biological samples can be useful for the determination of legal or illicit drugs consumption or interpretation of unexpected toxicological effects. Chiral substances can also be found in environmental samples and revealed to be useful for determination of comm...

The enantiomeric separation of basic drugs was successfully demonstrated by using a novel chiral microemulsion electrokinetic chromatography (MEEKC). An interesting finding was that the chiral oil core ((S)-(+)-2-octanol) within the microemulsion droplets appeared to play an important role in the chiral separation mechanism. In addition, the enantioselectivity of the analyte-selector complex co...