两个自由端促成环化反应

A peptide catalyst turns a linear molecule into a ring through two synchronous reactions Ziyang Dong1 and Changgui Zhao1,2 Macrocycles—ring-shaped molecules with 12 or more atoms—can bind to large, flat, or flexible protein surfaces that are inaccessible to traditionally small-molecule drugs. Their three-dimensional (3D) cyclic structures serve as preorganized keys that fit specific bioactive sites (1, 2). A macrocycle is often prepared through cyclization in which two ends of a linear precursor join to form a circle. However, existing cyclization methods require multiple synthesis steps. It is also difficult to control the resulting 3D structure because of the high energy barrier for a linear molecule to form a ring structure (3, 4). …