We report the discovery of a facile peptide macrocyclization and stapling strategy based on a fluorine thiol displacement reaction (FTDR), which renders a class of peptide analogues with enhanced stability, affinity, cellular uptake, and inhibition of cancer cells. This approach enabled selective modification of the orthogonal fluoroacetamide side chains in unprotected peptides in the presence of intrinsic cysteines. The identified benzenedimethanethiol linker greatly promoted the alpha helicity of a variety of peptide substrates, as corroborated by molecular dynamics simulations. The cellular uptake of benzenedimethanethiol stapled peptides appeared to be universally enhanced compared to the classic ring-closing metathesis (RCM) stapled peptides. Pilot mechanism studies suggested that the uptake of FTDR-stapled peptides may involve multiple endocytosis pathways in a distinct pattern in comparison to peptides stapled by RCM. Consistent with the improved cell permeability, the FTDR-stapled lead Axin and p53 peptide analogues demonstrated enhanced inhibition of cancer cells over the RCM-stapled analogues and the unstapled peptides.

我们报告了一种基于氟硫醇置换反应 (FTDR) 的简便肽大环化和装订策略的发现，该策略使一类肽类似物具有增强的稳定性、亲和力、细胞摄取和对癌细胞的抑制作用。这种方法能够在存在固有半胱氨酸的情况下选择性地修饰未受保护的肽中的正交氟乙酰胺侧链。经分子动力学模拟证实，已鉴定的苯二甲硫醇接头极大地促进了多种肽底物的 α 螺旋性。与经典的闭环复分解 (RCM) 钉肽相比，苯二甲硫醇钉肽的细胞摄取似乎普遍增强。试点机制研究表明，与 RCM 钉合的肽相比，FTDR 钉合肽的摄取可能涉及多种内吞途径，其模式不同。与改善的细胞通透性一致，FTDR 钉合的先导 Axin 和 p53 肽类似物表现出对癌细胞的抑制作用优于 RCM 钉合的类似物和未钉合的肽。