[reaction: see text] A convergent and concise route to an advanced precursor 2b of kendomycin (1) has been developed by applying a S(N)1 ring cyclization as a key step. The resulting C-aryl glycoside was initially isolated as a rotameric mixture, but after MOM protection of the o-hydroxyl of the phenol, the conformation was frozen to the desired kendomycin-like atropisomer.
[反应:见正文]通过应用S(N)1环环化作为关键步骤,已开发出一条趋于简明的途径合成肯德霉素(1)的高级前体2b。最初将所得的C-芳基糖苷分离为旋转异构体混合物,但是在对
苯酚的邻羟基进行MOM保护之后,将构象冷冻成所需的类似霉素的阻转异构体。