The Development and Validation of a Chiral High Performance Liquid Chromatography Method for the Identification and Quantification of (R)-Enantiomer in 10-Hydroxycamptothecin

A Venkateshwarlu,S V Subba Reddy,A V Rama Rao,Mukkanti Khagga

doi:10.5935/0103-5053.20130271

Abstract

A new and simple, rapid, isocratic, normal phase chiral high performance liquid chromatography (HPLC) method was developed and validated for the enantiomeric separation of (S)-10-hydroxycamptothecin (10-HCTN), ((4S)-4-ethyl-4,9-dihydroxy-1H-pyrano[3',4':6,7]indolizino[1,2-b] quinoline-3,14(4H,12H)-dione), an anti-cancer drug substance. The enantiomers of 10-HCTN were resolved on a Chiralpak IC (immobilized polysaccharide chiral stationary phase) column using a mobile phase consisting of n-hexane:ethanol (50:50 v/v) at a flow rate of 1.0 mL min-1. The resolution between both enantiomers was greater than 3 in the optimized method. The developed method was extensively validated and proved to be robust, enantioselective, accurate, precise, and suitable for quantitative determination of (R)-enantiomer in bulk drug substance and product.

Highlights

10-Hydroxycamptothecin (Figure 1a) is a potent DNA topoisomerase I inhibitor
10-HCTN is produced as a single isomer by a total synthesis and (R)-enantiomer could be present as a chiral impurity that is obtained in small amounts during the synthesis of 10-HCTN
To the best of our knowledge, no high performance liquid chromatography (HPLC) method is available in the literature for the chiral analysis of 10-HCTN.[9,10]

Summary

Introduction

10-Hydroxycamptothecin (Figure 1a) is a potent DNA topoisomerase I inhibitor. It induces apoptosis in human breast cancer cells. 10-HCTN is a single agent delivered by oral administration in the treatment of human colon cancer. 10-HCTN, a novel compound with an indole alkaloid structure, was clinically tested as a therapeutic agent by oral administration in the treatment of human colon cancer. The (S)-enantiomer has turned out to be a potent DNA topoisomerase I inhibitor.[5] No HPLC (high performance liquid chromatography) method is available in the literature for the chiral analysis of 10-HCTN. Separation of enantiomers has become very important in analytical chemistry, especially in the pharmaceutical and biological fields, because some stereoisomers of racemic drugs have quite different pharmacokinetics and different pharmacological or toxicological effects.[11,12]

Methods

Results

Conclusion