Patrick Camilleri

Chiral chromatography and multivariate quantitative structure-property relationships of benzimidazole sulphoxides

SummaryVarious benzimidazole sulphoxides were chirally resolved employing an amylase-based chiral stationary phase. The structure-property relationships of these compounds were investigated using calculated physico-chemical properties, molecular modelling and multivariate statistical techniques. A data set of 254 molecular descriptors was used to represent the series of compounds. Analysis of the data set using principal components analysis and non-linear mapping suggested that the separation factor of each enantiomeric pair was associated with nine molecular properties and, in particular, molar refractivity of the Z substituent and the partial charge of atom 6. The separation factor of a sulphoxide not used in the analysis was well predicted thus suggesting that these models may be used to generalize.

Molecular modelling studies and the chromatographic behaviour of oxiracetam and some closely related molecules

SummaryModelling studies have been carried out on the cellulose-based chiral stationary phase used to separate the enantiomers of three simple lactams. These studies have helped in understanding differences in the chromatographic behaviour of these molecules.

Direct resolution of the optical isomers of fenoldopam and one of its derivatives

In this Note we describe an analytical method that is suitable to differentiate between the optical isomers of fenoldopam. This method was also used to resolve the optical isomers, where the three hydroxy groups in fenoldopam have been replaced by methoxy substituents. These studies are expected to be relevant for pharmacokinetics and pharmacodynamic studies on fenoldopam.

Separation of the enantiomers of a triester of 2,2-difluorocitrate

Le triester du titre a ete separe par chromatographie HPLC et caracterise par polarimetrie et dichroisme circulaire