The data shown in this article are related to the subject of an article in Carbohydrate Polymers, entitled "Synthesis and characterization of chitosan alkyl urea" [1]. 1H NMR and 13C NMR spectra of chitosan n-octyl urea, chitosan n-dodecyl urea and chitosan cyclohexyl urea are displayed. The chemical shifts of proton and carbon of glucose skeleton in these chitosan derivatives are designated in detail. Besides, 1H NMR spectra of chitosan cyclopropyl urea, chitosan tert-butyl urea, chitosan phenyl urea and chitosan N,N-diethyl urea and the estimation of the degree of substitution are also presented. The corresponding explanations can be found in the above-mentioned article.

A series of chitosan bis(methylphenylcarbamate)-(isobutyrylamide) derivatives were synthesized by carbamylating chitosan isobutyrylamide with different methylphenyl isocyanates. Then the prepared chitosan derivatives were coated onto 3-aminopropyl silica particles, resulting in a series of new chiral stationary phases (CSPs) for high-performance liquid chromatography. It was observed that the chiral recognition abilities of these coated-type CSPs depended very much on the substituents on the phenyl moieties of the chitosan derivatives, the eluent composition, as well as the structure of racemates. As a typical example, the eluent tolerance of the prepared CSP with the best enantioseparation ability was investigated in detail, and the results revealed that the CSP exhibited extraordinary solvent tolerance and could still work without significant loss in enantioseparation capability after being flushed with chloroform (100%), ethyl acetate (100%) and even THF/n-hexane (70/30, v/v), while the traditional coated-type CSPs based on the cellulose and amylose derivatives, such as cellulose tris(3,5-dimethylphenylcarbamate) (CDMPC) and amylose tris(3,5-dimethylphenylcarbamate) (ADMPC), might be dissolved or highly swollen in these eluents. Therefore, the application of the resultant CSPs could address the problem of the dissolution and high swelling of traditional coated-type CSPs in some unusual eluents, broadening the possibility of eluent choice. In addition, a comparison of the prepared CSPs with the well known CDMPC- and ADMPC- based CSPs concerning the chiral recognition ability was also made. Separation performances achieved on the as-prepared CSPs in different eluents were found to be even superior to CDMPC- and ADMPC-based CSPs for the tested chiral compounds. In summary, we could safely draw the conclusion that the CSPs derived from chitosan isobutyrylamide derivatives were capable of excellent chiral recognition ability, and meanwhile possessed satisfactory eluent tolerance in a wider range of solvents.

The goal of this study was to develop new chiral stationary phases (CSPs) with high chiral recognition capability and high compatibility with the so-called “nonstandard solvents”. Seven new chitosan bis(phenylcarbamate)-(N-cyclobutylformamide) derivatives were synthesized from chitosan with high degree of deacetylation as a starting material. The corresponding chiral stationary phases (CSPs 1–7) were prepared with the chitosan derivatives as chiral selectors (CSs). The enantioseparation capability of CSPs 1–7 was evaluated by high performance liquid chromatography with nineteen analytes. In comparison with the CSPs of cellulose tris(3,5-dimethylphenylcarbamate) (CDMPC) and amylose tris(3,5-dimethylphenylcarbamate) (ADMPC), the prepared CSPs generally demonstrated excellent enantioseparation capability, particularly for the CSP derived from chitosan bis(3-chloro-4-methylphenylcarbamate)-(N-cyclobutylformamide). Moreover, the CSPs in the present study could separate some analytes better, making them complementary for enantioseparations with the CSPs of CDMPC and ADMPC. The tolerability of the CSP with the best enantioseparation capability to organic solvents was investigated. The results showed that it could work in pure ethyl acetate, pure chloroform, and a normal phase containing 70% tetrahydrofuran, which are prevented from enantioseparation by the coating type CSPs of CDMPC and ADMPC. As these chitosan derivatives were almost insoluble in most organic solvents, the corresponding CSPs can work in a wide range of mobile phases. In addition, the influence of the position and electron effects of methyl and chloro groups introduced onto the CSs and the composition of mobile phases on enantioseparation was also discussed.