Wood R, Bever EL, Snyder F. The GLC and TLC resolution of diastereoisomeric polyhydroxystearates and assignment of configurations.
Lipids 1966;
1:399-408. [PMID:
17805647 DOI:
10.1007/bf02532543]
[Citation(s) in RCA: 14] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/1966] [Indexed: 10/23/2022]
Abstract
Trifluoroacetate (TFA) derivatives of methyl 12-hydroxystearate, methyl ricinoleate, five positional isomers of methylthreo- anderythro-dihydroxystearate, four diastereoisomeric methyl 9,10-12-trihydroxystearates, and four racemic diastereoisomeric methyl 9,10-12,13-tetrahydroxystearates were prepared and analyzed by gas-liquid chromatography (GLC). The isomericthreo- anderythro-dihydroxystearates that had not previously been resolved by GLC were separated. Excellent resolution of the diastereoisomeric pairs of methylthreo- anderythro-9,10-12-triand and methylerythro, erythro- andthreo, threo-9,10-12,13-tetrahydroxystearates was obtained by GLC of their TFA derivatives. Analyses of these high-molecular-weight compounds were carried out on polar and nonpolar packed columns used routinely for methyl ester analysis.The various methyl mono-, di-, tri-, and tetrahydroxysterate esters were also analyzed by thin-layer chromatography (TLC) on Silica Gel G adsorbent layers and on Silica Gel G impregnated with sodium arsenite.Relative and absolute configurations were assigned to the various diastereoisomeric tri- and tetrahydroxysterates based on information obtained from GLC, TLC, synthetic ratios, and molecular-models.A micro hydroxylation method that gives quantitative yields ofthreo- anderythro-dihydroxy acids from various concentrations of C(18) monoene geometrical isomers was developed. Subsequent GLC analysis of the isomeric methyl dihydroxy TFA derivatives allows the quantitative determination of double-bond configuration on small samples without expensive or specialized equipment.
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