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The chiral recognition ability of the chiral stationary phase (CSP) consisting of curdlan (beta-1,3-glucan) triacetate coated on silica gel was clearly changed by the contacting solvents and heat treatment. The chiral recognition ability significantly decreased, particularly at temperatures above 45 degrees C, depending on the racemates. The molecular weight of the curdlan triacetate slightly influenced its ability. The recognition abilities of curdlan tricetate that was lost by heat treatment were partially recovered by contact with methanol. However, when it was contacted with ethanol a different selectivity was observed. The labile chiral recognition ability of curdlan triacetate is in striking contrast to the very stable chiral recognition of cellulose (beta-1,4-glucan) triacetate (Chiralcel OA). This difference may be ascribed to the conformational stability of the acetates consisting of curdlan (beta-1,3-glucan) and cellulose (beta-1,4-glucan) with different sugar linkages.

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Racemic compounds containing a phosphorus or a sulfur atom as a chiral center were resolved by high-performance liquid chromatography on optically active (+)-poly(triphenylmethyl methacrylate). The resolved compounds include insecticides such as O-ethyl O-(4-nitrophenyl) phenylphosphonothionate (EPN), O-(4-cyanophenyl)-O-ethyl phenylphosphonothionate (cyanofenfos), and 2-methoxy-4H-1,3,2-benzo-dioxaphosphorin 2-sulfide (salithion).

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