Synthesis of a-O- and a-S-Glycosphingolipids Related to Sphingomonous cell Wall Antigens Using Anomerisation
作者:Wayne Pilgrim、Ciaran O'Reilly、Paul Murphy
DOI:10.3390/molecules180911198
日期:——
Analogues of glycolipids from Spingomonadacaece with O- and S- and SO2-linkages have been prepared using chelation induced anomerisation promoted by TiCl4. Included are examples of the anomerisation of intermediates with O- and S-glycosidic linkages as well as isomerisation of β-thioglycuronic acids (β-glycosyl thiols). The β-O-glucuronide and β-O-galacturonide precursors were efficiently prepared using benzoylated trichloroacetimidates. β-Glycosyl thiols were precursors to β-S-derivatives. Triazole containing mimics of the natural glycolipids were prepared using CuI promoted azide-alkyne cycloaddition reactions in THF. The glycolipid antigens are being evaluated currently for their effects on iNKT cells.
来自Spingomonadacaece的糖脂类类似物,具有O-、S-和SO2-连接,通过TiCl4催化的螯合诱导的异构化进行了制备。其中包括具有O-和S-糖苷键的中间体异构化的例子,以及β-硫葡萄糖醇酸(β-糖苷硫醇)的异构化。β-O-葡萄糖醛酸酯和β-O-半乳糖醛酸酯的前体采用苯甲酰化三氯乙酰胺高效制备。β-糖苷硫醇是β-S-衍生物的前体。含有三唑的天然糖脂类模仿物使用CuI催化的叠氮烷炔环加成反应在THF中制备。当前正在评估这些糖脂抗原对iNKT细胞的影响。