Disclosed herein a sialyl donor and its use for the synthesis of gangliosides. The sialyl donor has the structure of,
wherein, R1 and R2 are independently benzoyl, toluenesulfonyl, pivaloyl or acetyl optionally substituted with a halogen; and R3 is acetyl or —(O)CCH2OH. In one preferred embodiment, in the sialyl donor of formula (I), R is acetyl. Also disclosed herein is a method of synthesizing a sialoside. The method comprises steps of: coupling the sialyl donor of formula (I) with a glycosyl acceptor having a primary hydroxyl group in the presence of N-iodosuccinimide (NIS) and trifluoromethanesulfonic acid (TfOH) under suitable conditions; and isolating the sialoside, which has an α-glycosidic linkage. According to preferred embodiments, the coupling is conducted in a solvent selected from the group consisting of, CH3CN, CH3Cl, and CH2Cl2 at a temperature between −20° C. to −60° C. Additionally or optionally, the coupling is conducted in CH2Cl2 with the presence of a powdered molecular sieve at −40° C.
本公开揭示了一种
唾液酸供体及其用于合成
神经节苷脂的用途。该
唾液酸供体的结构为,
其中,R1和R2独立地为苯甲酰基、
甲苯磺酰基、季戊酰基或乙酰基,可选择地被卤素取代;R3为乙酰基或—(O)CCH2OH。在一个首选实施例中,在式(I)的
唾液酸供体中,R为乙酰基。本公开还揭示了一种合成唾苷的方法。该方法包括以下步骤:在适当条件下,将式(I)的
唾液酸供体与具有主要羟基的糖基受体在N-
碘代琥珀
酰亚胺(NIS)和
三氟甲磺酸(TfOH)的存在下偶联;并分离具有α-糖苷键的唾苷,根据首选实施例,偶联在从CH3CN、
CH3Cl和
CH2Cl2组成的溶剂中,在-20°C至-60°C的温度下进行。此外或可选地,在-40°C时,在 中存在粉末
分子筛的情况下进行偶联。