Chiral HPLC of Antimalarial Drugs

widespread throughout the tropics. Similar drug resistance has rapidly developed to other, more potent, and sometimes more toxic, drugs such as primaq...

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HPLC

TN-1013

Chiral HPLC of Antimalarial Drugs Utility of Chirex™ Chiral Stationary Phases

Chloroquine Column: Dimensions: Order No.: Mobile Phase: Flow Rate: Detector:

Chirex 3014 250 x 4.6mm 00G-3014-EO-TN Hexane/Dichloroethane/Ethanol-TFA (50:35:15), with ethanol-TFA (20:1) 1.0mL/min UV @ 346nm

α=1.22

5.00

An active area of investigation involves possible combination therapies, where two or more of these drugs are administered in tandem. Since many of these old and new compounds are chiral, there is growing interest in determining the therapeutic efficacy of individual enantiomers and the potential development of drugs in optically pure form.

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Primaquine Column: Dimensions: Order No.: Mobile Phase:

10.33

Flow Rate: Detector:

Chirex 3014 250 x 4.6mm 00G-3014-EO-TN Hexane/Dichloroethane/Ethanol-TFA (50:35:10), with ethanol-TFA (20:1) 1.0mL/min UV @ 268nm 11.71

App ID 13682

Similar drug resistance has rapidly developed to other, more potent, and sometimes more toxic, drugs such as primaquine and quinacrine, Amodiaquine, Mefloquine, and Halofantrine. Recently, new and important contributions to treating malaria have come from China, with the development of qinghaosu or artemisinin. Other synthetics, such as piperaquine, lumefantrine, and pyronaridine are also providing clinicians with a new generation of effective, and in some cases, affordable antimalarial drugs.

14.08

For many years chloroquine was the safe and inexpensive drug of choice. In fact, two chiral drugs, chloroquine and pyrimethamine were used so widely (even as a regular additive to table salt), that many people had the drugs in their blood all the time. Unfortunately, resistance to these two compounds is now widespread throughout the tropics.

16.56

Introduction Malaria is probably the most important parasitic disease affecting humans today. Unfortunately, due directly to increasing antimalarial drug resistance, suffering and death in tropical latitudes continues to grow significantly. In fact, many antimalarial drugs are becoming useless.

App ID 13603

Tom Cleveland Phenomenex Inc., Torrance, CA, USA

α=1.18

Chirex HPLC columns offer superior tools to analyze and purify these new medicines for use in the war against malaria. In this Technical Note, simple and direct chiral HPLC methods for the resolution of racemic antimalarial drugs are described. 5.00

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Quinacrine

Flow Rate: Detector:

Chirex 3022 250 x 4.6mm 00G-3022-E0-TN Hexane/Dichloroethane/Ethanol-TFA (40:35:25), with ethanol-TFA (20:1) 1.0mL/min UV @ 282nm

Results & Discussion Various Chirex™ chiral stationary phases (CSPs) were evaluated for their utility to directly resolve (without derivatization) enantiomers of some important antimalarial compounds.

17.41

Column: Dimensions: Order No.: Mobile Phase:

13.77

App ID 13695

Instrumentation & Equipment Analyses were performed using an HP 1100 LC system (Agilent Technologies, Palo Alto, CA, USA) equipped with a quaternary pump, in-line degasser, multi-wavelength detector, and autosampler. HP Chemstation software was used for the data analysis. The HPLC columns used for the analysis are Chirex™ brand (Phenomenex, Torrance, CA, USA, see Ordering Information). Standards were purchased from Sigma (St. Louis, MO), Aldrich (Milwaukee, WI), or Fluka (Ronkonkoma, NY), depending on availability.

α=1.33

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HPLC

Table 1. Enantioresolution of three antimalarial drugs using Chirex CSPs

Antimalarial

Chloroquine

Primaquine

Quinacrine

TN-1013

Chirex CSP

Resolution (Rs)

App ID

Ordering Information: Chirex is available in a wide range of phases and column sizes, from analytical to preparative. All phases are also available in bulk (15 and 30µ particle size).

3020 3014

3.78 3.41

1.21 1.22

14.32 16.56

13604 13603

The columns discussed in this Note are listed below.

3022 3018 3014 3020 3022 3017 3020

2.86 4.49 3.54 3.27 6.12 2.71 2.10

1.13 1.20 1.18 1.16 1.33 1.38 1.10

16.51 25.94 11.71 18.07 17.41 8.21 26.99

13605 13606 5248 13683 13695 13694 13696

Separation Retention Time Factor Second peak (alpha) (min)

References 1. Cleveland, T., J. Liq. Chromatogr. 18(4): 649-671, 1995.

5µ Analytical Columns (mm) Chirex Phase and Bond Linkage, 250 x 4.6mm ID Phase Description 3001 3014

|

(R)-PGLY and DNB Covalent Amide

Order No. |

00G-3001-E0-TN

(S)-VAL and (R) NEA Covalent Urea

00G-3014-E0-TN 00G-3017-E0-TN

3017

(S)-PRO and (S) NEA Covalent Urea

3018

(S)-PRO and (R) NEA Covalent Urea

00G-3018-E0-TN

3019

(S)-LEU and (S) NEA Covalent Urea

00G-3019-E0-TN

3020

(S)-LEU and (R) NEA Covalent Urea

00G-3020-E0-TN

3022

(S)-ICA and (R) NEA Covalent Urea

00G-3022-E0-TN

2621_L

If you would like more information on these columns or any specific application listed, please contact Phenomenex. Also, if you are new to chiral HPLC or are doing method development work call us today to reserve your FREE copy of our 70-page Guidebook to Chiral HPLC Method Development.

For a digital copy of this Technical Note, please visit www.Phenomenex.com/TechNotes/1013 Copyright ©2004 Phenomenex Inc., CA, USA.. All rights reserved. Phenomenex is a registered trademark. Copying or re-use of this information is not allowed without written permission from Phenomenex.

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