The toxins TcdA and TcdB produced by the human pathogen Clostridium difficile gain entrance to host epithelial cells by recognizing cell-surface carbohydrate ligands. Inhibiting the attachment of these toxins to host cells has been proposed to be a viable therapy to treat C. difficile infections. Glycan array screening previously revealed that the LeA-LacNAc pentasaccharide binds strongly to TcdA. Here we report the efficient syntheses of the pentasaccharide and a structurally related tetrasaccharide motif. These compounds will be used to better define the carbohydrate-binding specificity of toxins from C. difficile, which will hopefully lead to the development of improved therapeutics.
人类病原体艰难梭菌产生的毒素 TcdA 和 TcdB 通过识别细胞表面
碳水化合物配体进入宿主上皮细胞。抑制这些毒素附着在宿主细胞上被认为是治疗艰难梭菌感染的一种可行疗法。之前的糖阵列筛选显示,LeA-LacNAc 五糖与 TcdA 有很强的结合力。在此,我们报告了五糖和结构相关的四糖的高效合成。这些化合物将用于更好地确定艰难梭菌毒素的
碳水化合物结合特异性,从而有望开发出更好的疗法。