Tang Shouwan, Jin Zhaolei, Sun Baishen, Wang Fang, Tang Wenyuan
Department of Chemistry, College of Pharmaceutical and Chemical Engineering, Taizhou University, Taizhou, People's Republic of China.
College of Pharmaceutical Science, Zhejiang University, Hangzhou, People's Republic of China.
Chirality. 2017 Sep;29(9):512-521. doi: 10.1002/chir.22720. Epub 2017 Jun 21.
Six novel regioselectively substituted amylose derivatives with a benzoate at 2-position and two different phenylcarbamates at 3- and 6-positions were synthesized and their structures were characterized by H nuclear magnetic resonance (NMR) spectroscopy. Their enantioseparation abilities were then examined as chiral stationary phases (CSPs) for high-performance liquid chromatography (HPLC) after they were coated on 3-aminopropyl silica gels. Investigations indicated that the substituents at the 3- and 6-positions played an important role in chiral recognition of these amylose 2-benzoate serial derivatives. The derivatives demonstrated characteristic enantioseparation and some racemates were better resolved on these derivatives than on Chiralpak AD, which is one of the most efficient CSPs, utilizing coated amylose tris(3,5-dimethylphenylcarbamate) as the chiral selector. Among the derivatives prepared, amylose 2-benzoate-3-(phenylcarbamate/4-methylphenylcarbamate)-6-(3,5-dimethylphenylcarbamate) exhibited chiral recognition abilities comparable to that of Chiralpak AD and may be useful CSPs in the future. The effect of mobile phase on chiral recognition was also studied. In general, with the decreased concentration of 2-propanol, better resolutions were obtained with longer retention times. Moreover, when ethanol was used instead of 2-propanol, poorer resolutions were often achieved. However, in some cases, improved enantioselectivity was achieved with ethanol rather than 2-propanol as the mobile phase modifier.
合成了六种新型的区域选择性取代直链淀粉衍生物，它们在2位带有苯甲酸酯，在3位和6位带有两种不同的苯基氨基甲酸酯，并通过氢核磁共振（NMR）光谱对其结构进行了表征。将它们涂覆在3-氨丙基硅胶上后，作为高效液相色谱（HPLC）的手性固定相（CSP）对其对映体分离能力进行了研究。研究表明，3位和6位的取代基在这些直链淀粉2-苯甲酸酯系列衍生物的手性识别中起重要作用。这些衍生物表现出特征性的对映体分离，一些外消旋体在这些衍生物上的分离效果比在Chiralpak AD上更好，Chiralpak AD是最有效的CSP之一，它使用涂覆的直链淀粉三（3,5-二甲基苯基氨基甲酸酯）作为手性选择剂。在所制备的衍生物中，直链淀粉2-苯甲酸酯-3-（苯基氨基甲酸酯/4-甲基苯基氨基甲酸酯）-6-（3,5-二甲基苯基氨基甲酸酯）表现出与Chiralpak AD相当的手性识别能力，未来可能是有用的CSP。还研究了流动相对手性识别的影响。一般来说，随着2-丙醇浓度的降低，分离度更好，但保留时间更长。此外，当使用乙醇代替2-丙醇时，通常会得到较差的分离度。然而，在某些情况下，以乙醇而非2-丙醇作为流动相改性剂时，对映选择性得到了提高。
