A series of tripeptidic proteasome inhibitors with furylketone as C-terminus were designed and synthesized. Biochemical evaluations against β1, β2 and β5 subunits revealed that they acted selectively on β5 subunit with IC₅₀s against chymotrypsin-like (CT-L) activity in micromolar range. LC-MS/MS analysis of the ligand-20S proteasome mixture showed that the most potent compound 11m (IC₅₀ = 0.18 μM) made no covalent modification on 20S proteasome. However, it was identified acting in a slowly reversible manner in wash-out assay and the reversibility was much lower than that of MG132, suggesting the possibility of these tripeptidic furylketones forming reversible covalent bonds with 20S proteasome. Several compounds were selected for anti-proliferative assay towards multiple cancer cell lines, and compound 11m displayed comparable potency to positive control (MG132) in all cell lines tested. Furthermore, the pharmacokinetic (PK) data in rats indicated 11m behaved similarly (C_max, 2007 μg/L; AUC_0−t, 680 μg/L·h; V_ss, 0.66 L/kg) to the clinical used agent carfilzomib. All these data suggest 11m is a good lead compound to be developed to novel anti-tumor agent.

设计合成了一系列以呋喃酮为C末端的三肽蛋白酶体抑制剂。针对β1，β2和β5亚基的生化评估表明，它们选择性地作用于β5亚基，IC ₅₀抑制微摩尔范围内的胰凝乳蛋白酶样（CT-L）活性。配体20S蛋白酶体混合物的LC-MS / MS分析表明，最有效的化合物11m（IC ₅₀ = 0.18μM）对20S蛋白酶体未进行共价修饰。但是，在洗脱分析中发现它以缓慢可逆的方式起作用，并且可逆性远低于MG132，这表明这些三肽呋喃酮与20S蛋白酶体形成可逆共价键的可能性。选择了几种化合物用于针对多种癌细胞系的抗增殖测定，并且化合物11m在所有测试的细胞系中显示出与阳性对照（MG132）相当的效能。此外，大鼠的药代动力学（PK）数据表明11m的行为与临床使用的卡非佐米类似（C _max，2007μg/ L； AUC _0-t，680μg / L·h； V _ss，0.66 L / kg）。所有这些数据表明11m是一种良好的铅化合物，将被开发为新型抗肿瘤药。