The driving force of homoand heterochiral complex formation in mixtures of chiral compounds is, probably, the effort of the system to separate the most symmetric associates from the less symmetric ones. A possible way to achieve separation of these associates is distribution between two phases. Therefore, during the separation of (a certain part) diastereoisomers similar trends can be observed ...

Three chiral robust diene-based porous organic frameworks (POFs) are prepared. POF- is shown to be an efficient heterogeneous catalyst after metallation for asymmetric conjugation addition with up to 93% ee, and it can also function as a new chiral stationary phase for gas chromatographic separation of racemates.

The separation of 17 chiral sulfoxides and eight chiral sulfinate esters by gas chromatography (GC) on four derivatized cyclodextrin chiral stationary phases (CSPs) (Chiraldex G-TA, G-BP, G-PN, B-DM) is presented. Many of these compounds are structural isomers or part of a homologous series. Differences in enantioselectivity of the methyl phenyl sulfoxide isomers on the derivatized gamma cyclod...

In order to improve the high-performance liquid chromatographic separation of alpha-amino acids derivatized with the fluorogenic reagent 4-fluoro-7-nitro-2,1,3-benzoxadiazole (NBD-F) on commercially available chiral stationary phases (CSPs) such as SUMICHIRAL OA-2500(S) (CSP 1) and OA-4700 (CSP 3), the preparation of two new CSPs (CSP 2 and CSP 4) having 11-aminoundecanoic acid between the amin...

In the present paper the separation of three amino acids applying ligand exchange chromatography in single and dual chiral systems was modeled using the dispersive equilibrium model. The investigated systems consist of a commercially available non chiral column and a commercially available chiral column using a chiral mobile phase. With the experimentally determined model parameters and the mul...

L-Phenylalanine (L-Phe) and D-Phenylalanine (D-Phe) imprinted poly [(acrylonitrile)-co-(acrylic acid)] membranes were prepared by wet phase inversion method for chiral separation. The chiral separation ability of molecularly imprinted copolymer membranes towards the underivatized D,L-Phe aqueous mixture was evaluated by ultrafiltration experiment. The novel membranes show continuous permselecti...

The chiral separation of a new antianginal agent has been investigated on a chiral cellulose column with UV and circular dichroism (CD) detection. This benzoxathiepin derivative under development has two stereogenic centers whose (R,S) stereoisomer shows an interesting antianginal activity. After optimisation of the mobile phase composition, a baseline-resolved separation of the four stereoisom...

The emergence of biochemical homochirality was a key step in the origin of life, yet prebiotic mechanisms for chiral separation are not well constrained. Here we demonstrate a geochemically plausible scenario for chiral separation of amino acids by adsorption on mineral surfaces. Crystals of the common rock-forming mineral calcite (CaCO(3)), when immersed in a racemic aspartic acid solution, di...

We discuss the calculation of the strange magnetic radius of the proton in chiral perturbation theory. In particular we investigate the low energy component of the loop integrals involving kaons. We separate the chiral calculation into a low energy part and a high energy component through use of a momentum space separation scale. This separation shows that most of the chiral calculation comes f...

A positively charged chiral stationary phase (CSP) was prepared by chemically immobilizing cellulose 3,5-dimethylphenylcarbamate onto methacryloyldiethylenetriaminopropylated silica (MCDEAPS) via a radical copolymerization reaction. The prepared CSP was evaluated for enantiomer separation in nonaqueous capillary electrochromatography (CEC). Electroosmotic flow (EOF) generated on the prepared CS...