Abstract
Author(s): Deepali Gangrade, Rajesh Nema and Indrajeet Singhvi
The Preparative Chiral Separation with Crown ether based Chiral Stationary Phases was utilized for resolving racemic Vince Lactam compound into the desired (-) Lactam and the undesired (+) Lactam. After the resolution of Vince Lactam, (+) Lactam was protected using Di-tert-butyl dicarbonate to form carbonate ester. This carbonate ester then reacts with amines to give tert-butyl (1S, 4R)-3-oxo-2-azabyclo [2.2.1] hept-5-ene-2-carboxylate. Further this protected Lactam is reduced with Sodium Borohydride, to form tert-butyl [(1S, 4R)-4-hydroxymethyl) cyclopent-2-en-1-yl]carbamate. This amide compound is further hydrolyzed to deprotect the (di-tert-butyl dicarbonate) BOC protected amino group using dilute hydrochloric acid to form an undesired isomer of amino alcohol compound - (1R, 4S)-4-Amino cyclopent-2-en-1-yl Methanol HCl. The reverse phase Enantioselective High Performance Liquid Chrsomatography method was developed for the separation of (1R, 4S)-4-Aminocyclopent-2-en-1-yl Methanol HCl and desired isomer (1S,4R) -4- Aminocyclopent-2-en-1-yl Methanol HCl, a key raw material used in the manufacturing processes of Abacavir Sulphate. The enantiomers of 4- Aminocyclopent-2-en-1-yl Methanol were resolved on Daicel Crown pack (+) (15cm x 4.0mm, 5µ) column using a mobile phase 50mM Sodium Perchlorate and pH of the solution was adjusted to 2.0 with perchloric acid. The resolution between the enantiomers was found to be more than 2.0.The method was validated as per International Conference of Harmonization (ICH) guidelines in terms of Limit of detection (LOD), Limit of quantitation (LOQ), linearity, precision, accuracy, specificity, robustness and solution stability. The LOD and LOQ values were found to be 0.6µg/ml and 2.0µg/ml, respectively for 2.5µL injection volume. The sample concentration injected was 5mg/ml. The method is linear within the range of 2.0-7.5µg/ml for (1R, 4S) Isomer
