Enantiomer Separation of a Novel Aminothiazolecarboxamide Fungicide Using Polysaccharide-Derived Chiral Stationary Phases

Abstract

The direct enantioseparation of a novel aminothiazolecarboxamide fungicide, ethaboxam, on polysaccharide-derived chiral stationary phases (CSPs) is described. Good resolution is achieved with several polysaccharide-derived CSPs. Chiralcel OD (OD-H) and Chiralpak AS are excellent for direct enantiomer separation of ethaboxam. The elution behavior and the effects of eluent composition on the resolution of ethaboxam are also investigated. Furthermore, the mechanism for chiral recognition using molecular mechanics is discussed.

Chiral Recognition of N‐Phthaloyl, N‐Tetrachlorophthaloyl, and N‐Naphthaloyl α‐Amino Acids and Their Esters on Polysaccharide‐Derived Chiral Stationary Phases

“…1,2 Among them, N-phthaloyl (PHT) group has been widely used in organic and peptide synthesis. 12,[15][16][17][18] The investigation of chiral recognition is hardly difficult in polysaccharide CSPs, because a number of structural peculiarities exist due to the presence of several stereogenic centers of the glucopyranose units and their helical structures of the polymer backbone. 6 And also, N-naphthaloyl (NPHT) group has been usefully used in the determination of enantiomeric excess as a chiral solvating agent.…”

“…[3][4][5] N-tetrachlorophthaloyl (TCPHT) group has been applied to solid-phase synthesis of C-terminal peptide amides. 19 The chiral discrimination mechanisms in polysaccharide CSPs have been examined using spectroscopic methods, [20][21][22] computer-aided methods, 17,18,20,23 and quantitative structure-retention relationship studies. [7][8][9] In order to utilize these useful N-protected a-amino acid derivatives, it is necessary to establish adequate analytical method diversely for the enantiomer separation.…”

“…[7][8][9] In order to utilize these useful N-protected a-amino acid derivatives, it is necessary to establish adequate analytical method diversely for the enantiomer separation. 17,18 In this study, we present liquid chromatographic results for the enantiomer separation of N-PHT, N-TCPHT, and N-NPHT a-amino acids and their esters with polysaccharide-derived CSPs. [10][11][12][13][14] Liquid chromatographic enantiomer separation has been frequently employed in evaluation of the enantiomeric purity with polysaccharide-derived chiral stationary phases (CSPs) that can separate a wide range of racemic compounds.…”

“…[10][11][12][13][14] Liquid chromatographic enantiomer separation has been frequently employed in evaluation of the enantiomeric purity with polysaccharide-derived chiral stationary phases (CSPs) that can separate a wide range of racemic compounds. 12,[15][16][17][18] The investigation of chiral recognition is hardly difficult in polysaccharide CSPs, because a number of structural peculiarities exist due to the presence of several stereogenic centers of the glucopyranose units and their helical structures of the polymer backbone. 19 The chiral discrimination mechanisms in polysaccharide CSPs have been examined using spectroscopic methods, [20][21][22] computer-aided methods, 17,18,20,23 and quantitative structure-retention relationship studies.…”

“…12,[15][16][17][18] The investigation of chiral recognition is hardly difficult in polysaccharide CSPs, because a number of structural peculiarities exist due to the presence of several stereogenic centers of the glucopyranose units and their helical structures of the polymer backbone. 19 The chiral discrimination mechanisms in polysaccharide CSPs have been examined using spectroscopic methods, [20][21][22] computer-aided methods, 17,18,20,23 and quantitative structure-retention relationship studies. 24,25 In previous work, we reported that computational calculations showed good agreement with chromatographic results of enantiomer separation on polysaccharide-derived CSPs.…”