Complex of a new racemic thiourea substrate: Spectrophotometric study and separation of atropisomers

The activity of a chiral molecule can vary from one atropisomer to the other. In this study, the separation of racemic-N-(2-methylphenyl), N’-(2-chlorophenyl) thiourea (H 2 L 2 ), a hydrophobic heavy metal trap, has been studied using reversed-phase high-performance liquid chromatography (RP-HPLC) with hydroxypropyl-beta-cyclodextrin (HP-β-CD) as a complexing additive to the racemic mixture and hexane-isopropanol as a mobile phase. The stoichiometry and the overall association constant of the complex have been determined using the continuous variation (Job's plot) method and the Scott's method respectively.