•Synthesis and chiral recognition of novel amylose derivatives.•Novel amylose derivatives bearing regioselective substituent at 2,6- and 3-positions.•Regioselective protection at 2,6-positions using bulky thexyldimethylsilyl group.•Racemic compounds better resolved on the obtained CSPs than Chiralpak AD.•Chiral recognition intricately depends on the substituents.Eighteen novel amylose derivatives bearing different phenylcarbamate substituents at 2,6- and 3-positions of a glucose ring were synthesized through the regioselective protection at 2- and 6-positions using a bulky trialkylsilyl chloride. Their chiral recognition abilities were then evaluated as the chiral stationary phases (CSPs) for high-performance liquid chromatography (HPLC) after coating them on the surface of macroporous silica gel. The chiral recognition abilities of these CSPs intricately depended on the nature, position and number of the substituents on the phenyl moieties. The introduction of substituents at meta-position of aromatic moieties at 2- and 6-positions of glucose unit was more attractive than other positions to improve the chiral recognition ability of these amylose derivatives. Each CSP seems to possess its own characteristic resolving power, and those based on amylose 3-(3,5-dichlorophenylcarbamate) showed comparatively better chiral recognition than others. For some racemates, the amylose derivatives with different phenylcarbamate substituents at 2,6- and 3-positions exhibited higher enantioselectivity than the amylose tris(3,5-dimethylphenylcarbamate), which is commercially available as Chiralpak AD, one of the most powerful CSPs. The structures of the obtained amylose derivatives were also investigated by circular dichroism spectroscopy.

•Fourteen chitosan 3,6-diphenylcarbamate-2-urea derivatives were synthesized.•Electron-withdrawing or -donating groups can obtain high chiral recognition ability.•Chiral recognition ability depends on position, nature and number of substituents.•Coated CSPs based on the chitosan derivatives could be used with nonstandard eluents.•Correlations between chiral recognition and N-H chemical shifts and IR frequencies.Fourteen chitosan 3,6-diphenylcarbamate-2-urea derivatives were synthesized using well-deacetylated chitosan and the corresponding phenyl isocyanates. After coating them on silica gel, their chiral recognition abilities were evaluated as the chiral stationary phases (CSPs) for high-performance liquid chromatography. These coated-type CSPs exhibited different chiral recognitions depending on the position, nature, and number of the substituents introduced on the phenyl group, and the introduction of either an electron-withdrawing or an electron-donating substituent improved the chiral recognition of the CSPs. Among the CSPs, the 2-substituted CSPs showed low chiral recognition abilities, while those with 3,5-dimethyl and 3,5-dichloro substituents showed relatively higher chiral recognition abilities, which enabled the baseline separation of some racemates. The CSPs could be used with some eluents containing chloroform, which cannot be used for other polysaccharide-based CSPs. Some racemates were more efficiently resolved with these nonstandard eluents. The correlation between the chiral recognition ability and the chemical shifts of the N-H protons in the 1H NMR spectra of the chitosan derivatives or the N-H frequencies in the IR spectra of the carbamate moieties was discussed.

Six ortho- and six meta-substituted phenylcarbamate derivatives of amylose were prepared and their chiral recognition abilities were evaluated as chiral stationary phases (CSPs) for high-performance liquid chromatography (HPLC). The substitution at the meta-position on the aromatic ring was more preferable than that at the ortho-position to obtain CSPs with a high chiral recognition ability, and the introduction of either an electron-withdrawing or electron-donating substituent can improve the chiral resolving power of the meta-substituted phenylcarbamates of amylose. The chiral recognition ability of the amylose phenylcarbamates and elution order of the enantiomers were significantly dependent on the position, nature and number of the substituents on the phenyl group. Correlations between the chiral recognition ability and the N–H frequencies in the IR spectra and the chemical shifts of the N–H protons in the 1H NMR spectra of the carbamate moieties of the amylose derivatives were discussed. The structures of the amylose derivatives were also investigated by circular dichroism spectroscopy.Highlights► Ortho- and meta-substituted phenylcarbamate derivatives of amylose. ► Meta-substitution is more preferable to obtain high chiral recognition ability. ► Chiral recognition ability depends on position, nature and number of substituents. ► Correlations between structural properties of substituents and chiral recognition. ► Correlations between chiral recognition and IR frequencies and N–H chemical shifts.