Ring closing metathesis and cross metathesis approaches to a new macrocyclic peptidomimetic aldehyde 2 have been developed, with the former route being the most convenient. Aldehyde 2 is a potent inhibitor of calpain II (IC50 of 45 nM) with comparable activity to the benchmark acyclic inhibitor SJA6017 4. Both compounds contain an N-terminal 4-fluorophenylsulfonyl group. The P2 Ile analogue of 2 (16) is significantly less active (IC50 of 2000 nM) which reflects an unusually subtle importance of the P2 residue for active site binding.
我们采用闭环复分解法和交叉复分解法开发出了一种新的大环拟肽醛 2,其中前一种方法最为方便。醛 2 是一种有效的钙蛋白酶 II 抑制剂(IC50 为 45 nM),其活性与基准无环抑制剂 SJA6017 4 相当。2 的 P2 Ile 类似物(16)的活性明显较低(IC50 为 2000 nM),这反映了 P2 残基对活性位点结合的异常微妙的重要性。