Development of New Cysteine Proteinase Inhibitors Involving the Generation of Conjugated Allenyl Esters as the Latent Active Species

以半胱氨酸蛋白酶的生物有机化学为背景，在我们对酶和非酶手性诱导对b-对称二酯和二胺的一系列研究的基础上，我们设想二乙基α -炔基丙二酸酯（DAM）作为开发组织蛋白酶抑制剂的新的先导化合物。酶（用PLE）和碱性水解各种DAM衍生物的乙氧羰基，然后脱羧，产生相应的烯丙酯，这些烯丙酯与EtSH发生化学选择性反应，得到硫醇加合物。正如我们预期的那样，这些DAM衍生物在体外对组织蛋白酶B和L的水解表现出显著的抑制作用，其M浓度顺序为10^<-4>-10^<-5>。含有组织蛋白酶B识别片段的DAM-NH-L-Ile-Pro-CO_2H衍生物在其10^<-6>-10^<-7>M浓度顺序上抑制组织蛋白酶B的酶解。由相应的DAM-NH-L-Ile-L-Pro-CO_2H衍生的新化合物pyrolin -2-one- nh - l - ile - l - pro - co_2h在1^<-7>M下选择性抑制组织蛋白酶B的酶活性（抑制率91%）。dam - nh -L- ph - nhbzl和吡咯啉-2- 1 - nh -L- ph - nhbzl抑制组织蛋白酶L酶解的浓度顺序为10^<-6> M -10^<-7>M。

With the background of bioorganic chemistry of cysteine proteinases and on the basis of a series of studies on enzymatic and non-enzymatic chiral induction on to b-sysmmetric diesters and diamides by us, we envisaged dietthl alpha-alkynylmalonates (DAM) as new lead compounda for developing the cathepsin inhibitors. Enzymatic(with PLE) and alkaline hydrolyses of an ethoxycarbonyl group of various DAM derivatives followed by decarboxylation produced the corresponding allenylesters, which reacted chemoselectively with EtSH to give the thiol adducts. As we anticipated, these DAM derivatives exhibited significant inhibition in their 10^<-4>-10^<-5>M concentration order against the hydrolysis with cathepsins B and L in vitro. DAM-NH-L-Ile-Pro-CO_2H derivatives bearing the cathepsin B-recognition moiety inhibited the enzymatic hydrolysis with cathepsin B in their 10^<-6>-10^<-7>M concentration order. A new compound, pyrrolin-2-one-NH-L-Ile-L-Pro-CO_2H derived from the corresponding DAM-NH-L-Ile-L-Pro-CO_2H inhibited selectively theenzymatic action of cathepsin B at 1^<-7>M (91% inhibition). DAM-NH-L-Phe-NHBzl and pyrrolin-2-one-NH-L-Phe-NHBzl inhibited the enzymatic hydrolysis with cathepsin L in their 10^<-6>-10^<-7>M concentration order.