多糖类氨基甲酸酯衍生物的区域选择性合成及其手性识别

通过糖单元6-位羟基的保护和去保护,运用区域选择性方法合成了6种新型多糖类氨基甲酸酯衍生物,分别为纤维素/直链淀粉-2,3-二(3,5-二甲基苯基)-6-环己基]氨基甲酸酯、2,3-二(3,5-二氯苯基)-6-环己基]氨基甲酸酯及2,3-二(4-氯苯基)-6-环己基]氨基甲酸酯,并将其涂敷在氨丙基硅胶的表面制备HPLC手性固定相.利用1H-NMR与FTIR光谱技术对所合成衍生物进行结构表征和分析,并应用HPLC法评价其对于9种手性化合物的手性识别能力.通过与以手性识别能力高而著称且含有单一取代基的纤维素/直链淀粉-三(3,5-二甲基苯基氨基甲酸酯)等手性固定相的对比分析表明,所合成新型手性固定相对于某些对映体显示出更优的手性识别能力.由进一步分析表明,糖单元2-、3-和6-位取代基的性能对于纤维素和直链淀粉氨基甲酸酯类衍生物的手性识别能力均具有较大影响.

SYNTHESIS AND CHIRAL RECOGNITION OF POLYSACCHARIDE CARBAMATE DERIVATIVES BEARING REGIOSELECTIVE SUBSTITUENTS

Six new polysaccharide carbamate derivatives,6-cyclohexyl-2,3-bis(3,5-dimethylphenyl)]-carbamate,6-cyclohexyl-2,3-bis(3,5-dichlorophenyl)]carbamate and 6-cyclohexyl-2,3-bis(4-chlorophenyl)]carbamate of cellulose and amylose,were synthesized by a sequential regioselective process based on the protection and deprotection of 6-position of a glucose unit.These derivatives were then used as the chiral stationary phases(CSPs) for high-performance liquid chromatography(HPLC) after being coated on the surface of aminopropyl silica gel.The structures of the obtained derivatives were characterized by 1H-NMR and FTIR spectroscopies,and their chiral recognition abilities were evaluated using nine racemates by HPLC.Some racemates were better resolved on the new derivatives,compared with the well-known monosubstituted and disubstituted phenylcarbamate derivatives,such as tris(3,5-dimethylphenylcarbamate),tris(3,5-dichlorophenylcarbamate),tris(4-chlorophenylcarbamate) and tris(cyclohexylcarbamate) of the cellulose and amylose with high chiral recognition ability.The higher order structure of the new derivatives seems to be changed through the selective introduction of a cyclohexyl group onto the 6-position of the glucose unit,which must influence the chiral recognition ability of the new derivatives.The obtained results indicate that three novel cellulose derivatives show higher chiral recognition ability than three amylose derivatives for most of the racemates in the study.And the property and position of substituents at 2-,3-and 6-position of glucose unit have a great influence on the chiral recognition ability of cellulose and amylose carbamate derivatives.