Unusual retention behavior of omeprazole and its chiral impurities B and E on the amylose tris (3-chloro-5-methylphenylcarbamate) chiral stationary phase in polar organic mode

Abstract

Recent reports have demonstrated that the new commercially available immobilized-type chiral stationary phases (CSPs) containing amylose tris(3-chloro-5-methylphenylcarbamate) (ACMPC) as a selector exhibit not only an exceptionally high enantioselectivity in high-performance liquid chromatography (HPLC) but they are also applicable to a wide range of chiral analytes. Herein, we report the results obtained in the HPLC analysis of omeprazole and its impurities B and E on the ACMPC-based Chiralpak IG-3 CSP (CSP) under polar organic conditions. A systematic evaluation of the retention characteristics of the selected benzimidazole chiral probes was carried out by changing the composition of the mobile phase and the column temperature. It is worth emphasizing that the high affinity of both enantiomers of all analytes recorded in pure methanol mode dramatically decreased incorporating small volumes of either basic or acid additives in the mobile phase. Unspecified sites of the IG-3 CSP presumably involved in strong and non-stereoselective H-bonding contacts with chiral analytes are assumed responsible for the unproductive retention process.

A chromatographic study on the retention behavior of the amylose tris(3‐chloro‐5‐methylphenylcarbamate) chiral stationary phase under aqueous conditions

“…In fact, in aprotic polar organic mode, the first enantiomer of OXFZ was not eluted from the IG-3 column after 50 min. Such uncommon retentive behavior has already been observed on the same CSP using omeprazole as a selectand [4].…”

“…It has been prepared by immobilizing amylose tris(3‐chloro‐5‐methylphenylcarbamate) (ACMPC) onto 3 μm particles of silica. Previous works have demonstrated that ACMPC‐based CSPs can be successfully used for the direct resolution of different biologically active compounds in combination with typical normal phase and polar organic mobile phases . However, its use for HPLC enantioseparations with aqueous eluents has not been evaluated yet.…”

“…It has been prepared by immobilizing amylose tris(3-chloro-5methylphenylcarbamate) (ACMPC) onto 3 μm particles of silica. Previous works have demonstrated that ACMPC-based CSPs can be successfully used for the direct resolution of Article Related Abbreviations: ACMPC, amylose tris(3-chloro-5-methylphenylcarbamate); ACN, acetonitrile; CSP, chiral stationary phase; CD, circular dichroism; DEA, diethylamine; HB, hydrogen-bonding; OXFZ, oxfendazole different biologically active compounds in combination with typical normal phase and polar organic mobile phases [1][2][3][4][5]. However, its use for HPLC enantioseparations with aqueous eluents has not been evaluated yet.…”

Chiral separation in the class of proton pump inhibitors by chromatographic and electromigration techniques: An overview

“…This phenomenon was explained as being caused by the non‐stereoselective hydrogen bondings between analytes and the CSP, which can be minimized in this way. The influence of temperature was also evaluated, while the enantioseparations of OME and Impurity‐E were found to be unusually entropically – driven whereas the resolution of Impurity‐B was an enthalpically – driven process [77].…”

Single-run reversed-phase HPLC method for determining sertraline content, enantiomeric purity, and related substances in drug substance and finished product

“…In the Chiralpak IG-3 CSP, the amylose tris(3-chloro-5-methylphenylcarbamate) (ACMPC) polymeric selector was immobilized onto 3-μm silica particles [ 8 ]. Recent studies showed that meta-substituted ACMPC-based CSPs can be successfully applied to develop enantioselective HPLC protocols useful for the resolution of biologically active chiral compounds [ [9] , [10] , [11] ] in both normal-phase and aqueous modes [ 12 , 13 ]. In addition, the ACMPC selector was also shown to be effective for the simultaneous separation of structurally related chiral analytes [ 8 , [12] , [13] , [14] , [15] , [16] ].…”