Stereoselective high-performance liquid chromatography and analytical method characterization of evacetrapib using a brush-type chiral stationary phase: a challenging isomeric separation requiring a unique eluent system.

Using HPLC chiral separation screening, various columns representing the polysaccharide, macrocyclic antibiotic and brush classes were assessed in multiple chromatographic modes for the separation of evacetrapib, a potential cardiovascular drug, from its enantiomer, two diastereomers and several impurities. Screening data consistently pointed to the brush-type Whelk-O 1 chiral column as most promising for this task. A systematic separation optimization process is outlined using the (S,S) Whelk-O 1 chiral column, first for the resolution of the isomers, and later including six potential impurities. A relatively complex yet rugged separation system was eventually identified that effectively resolves all compounds within a reasonable analysis time, and should serve as an adequate tool for evacetrapib bulk drug enantiopurity measurement.