Disclosed is to a laevorotatory enantiomer of the configurational stereoisomer of difethialone, named hetero-stereoisomer, the formula of which is 3-(4-bromobiphenyl-4-yl)-1-(4-hydroxythiocoumarin-3-yl)-1,2,3,4-tetrahydronaphthalene, in which carbons 1 and 3 of the 1,2,3,4-tetrahydronaphthalene group have different absolute configurations.

The present invention relates to a novel stationary phase support for liquid chromatographic chiral separations. The specific combination of the special underlying support material and certain classes of known chiral selectors according to the invention produces far superior chiral (enantiomeric) separations than those obtained on any conventionally known supports. These chiral (enantiomeric) separations are enhanced in terms of significantly higher efficiencies (theoretical plate numbers), higher resolutions (R.sub.s), shorter retention times and either equivalent or slightly higher selectivities than those obtained on conventional supports.

The present invention provides novel chromatographic materials, e.g., for chromatographic separations, processes for its preparation and separations devices containing the chromatographic material; separations devices, chromatographic columns and kits comprising the same; and methods for the preparation thereof. The chromatographic materials of the invention are high purity chromatographic materials comprising a chromatographic surface wherein the chromatographic surface comprises a hydrophobic surface group and one or more ionizable modifier.

Provided are two-dimensional chromatography systems and methods for separating and/or analyzing complex mixtures of organic compounds. In particularly, a two-dimensional reversed-phase liquid chromatography (RPLC)supercritical fluid chromatography (SFC) system is described including a trapping column at the interface which collects the analytes eluted from the first dimension chromatography while letting the RPLC mobile phase pass through. The peaks of interest from the RPLC dimension column are effectively focused as sharp concentration pulses on the trapping column, which is subsequently injected onto the second dimension SFC column. The system can be used for simultaneous achiral and chiral analysis of pharmaceutical compounds. The first dimension RPLC separation provides the achiral purity result, and the second dimension SFC separation provides the chiral purity result (enantiomeric excess).

Disclosed is a laevorotatory enantiomer of the configurational stereoisomer of difethialone, named homo-stereoisomer, the formula of which is 3-(4-bromobiphenyl-4-yl)-1-(4-hydroxythiocoumarin-3-yl)-1,2,3,4-tetrahydronaphthalene, in which carbons 1 and 3 of the 1,2,3,4-tetrahydronaphthalene group have the same absolute configuration.

Disclosed is a configurational stereoisomer, referred to as enantiomer E.sub.4, of flocoumafen, the enantiomer E.sub.4 having, as determined by the chromatographic analysis of flocoumafen including four configurational stereoisomers of flocoumafen, carried out under conditions described hereinafter, a retention time t.sub.4 with a value such that t.sub.1<t.sub.2<t.sub.3<t.sub.4; t.sub.1, t.sub.2 and t.sub.3 representing the retention times of the configurational stereoisomers of flocoumafen different from the enantiomer E.sub.4, the analysis being carried out at a temperature of 23.5 C.

Disclosed is a configurational stereoisomer, named enantiomer E.sub.1, of flocoumafen, the enantiomer E.sub.1 having, by chromatographic analysis of flocoumafen performed under particular conditions, a retention time t.sub.1 having a value such that t.sub.1<t.sub.2<t.sub.3<t.sub.4; t.sub.2, t.sub.3 and t.sub.4 representing the retention times of the configurational stereoisomers of flocoumafen different from the enantiomer E.sub.1, the analysis being performed at a temperature of 23.5 C.

The present invention provides novel chromatographic materials, e.g., for chromatographic separations, processes for its preparation and separations devices containing the chromatographic material; separations devices, chromatographic columns and kits comprising the same; and methods for the preparation thereof. The chromatographic materials of the invention are high purity chromatographic materials comprising a chromatographic surface wherein the chromatographic surface comprises a hydrophobic surface group and one or more ionizable modifier.

Disclosed is a composition including flocoumafen and an amount of a configurational stereoisomer of flocoumafen, named enantiomer E.sub.4, such that the ratio of this amount to the amount of flocoumafen in the composition is less than 10%, the enantiomer E.sub.4 being present with the exclusion of a racemic mixture, the enantiomer E.sub.4 having, by chromatographic analysis of flocoumafen, a retention time t.sub.4 having a value such that t.sub.1<t.sub.2<t.sub.3<t.sub.4; t.sub.1, t.sub.2 and t.sub.3 representing the retention times of the configurational stereoisomers of flocoumafen different from the enantiomer E.sub.4, the chromatographic analysis being performed at a temperature of 23.5 C.

Disclosed is a configurational stereoisomer, named enantiomer E.sub.3, of bromadiolone having, by chromatographic analysis of a bromadiolone composition including four configurational stereoisomers of bromadiolone performed under the conditions described hereinbelow, a retention time t.sub.3 having a value such that t.sub.1<t.sub.2<t.sub.3<t.sub.4; t.sub.1, t.sub.2 and t.sub.4 being the retention times of the configurational stereoisomers of bromadiolone different from the enantiomer E.sub.3, the analysis being performed at a temperature of 27.3 C.