Regioselectivity in acylation of oligosaccharides catalyzed by the metalloprotease thermolysin
作者:Ignacio Pérez-Victoria、Juan Carlos Morales
DOI:10.1016/j.tet.2005.11.066
日期:2006.3
immobilized on Celite as biocatalyst has been carried out. The reactions were performed in DMSO, a good solvent for carbohydrates, where the enzyme has previously shown its activity in transesterifications of sucrose, maltose and maltose-containing oligosaccharides. Surprisingly, no reaction was observed for glucose or the glucose-containing disaccharides, trehalose and lactose. In contrast, laurate monoesters
已经研究了通过固定在作为生物催化剂的硅藻土上的金属蛋白酶嗜热菌素对碳水化合物的酰化范围的研究。反应是在DMSO(一种很好的碳水化合物溶剂)中进行的,该酶先前在蔗糖,麦芽糖和含麦芽糖的寡糖的酯交换反应中已显示出其活性。令人惊讶地,未观察到葡萄糖或含葡萄糖的二糖,海藻糖和乳糖的反应。相反,使用月桂酸乙烯酯作为酰化剂,通过一步酯交换反应,合成了几种含蔗糖的三糖和四糖的月桂酸酯单酯。通过HPLC / MS准确确定了酶的区域选择性,并结合NMR实验确定了主要的区域异构体的结构。在所有情况下,酰化的优选位置是α-d-吡喃葡萄糖部分的2-OH以1→2连接至β-d-果糖呋喃糖单元。这些结果与在二糖蔗糖的情况下观察到的区域选择性相关。提出了通过嗜热菌素催化的一般碳水化合物结合基序。