Dipeptides Containing L-Arginine Analogs: New Isozyme-Selective Inhibitors of Nitric Oxide Synthase.
作者:Nobutaka KOBAYASHI、Tsunehiko HIGUCHI、Yasuteru URANO、Kazuya KIKUCHI、Masaaki HIROBE、Tetsuo NAGANO
DOI:10.1248/bpb.22.936
日期:——
Several L-arginine analogs are known as potent inhibitors of nitric oxide synthase (NOS). We recently synthesized dipeptides containing such amino acids, and found that they are potent and isozyme-selective NOS inhibitors. For example, S-methyl-L-isothiocitrullinyl-L-phenylalanine showed 66-fold selectivity for iNOS over nNOS, while S-methyl-L-isothiocitrullinyl-L-leucine and N(G)-nitro-L-argininyl-L-phenylalanine
几种L-精氨酸类似物被称为一氧化氮合酶(NOS)的有效抑制剂。我们最近合成了包含此类氨基酸的二肽,并发现它们是有效的同工酶选择性NOS抑制剂。例如,S-甲基-L-异硫代瓜氨酸基-L-苯丙氨酸对iNOS的选择性是nNOS的66倍,而S-甲基-L-异硫代瓜氨酸基-L-亮氨酸和N(G)-硝基-L-精氨酸基-L-苯丙氨酸分别显示出20倍和14倍的选择性。有趣的是,S-甲基-L-异硫代瓜氨酸基-D-苯丙氨酸没有选择性,而S-甲基-L-异硫代瓜氨酸基-L-苯丙氨酸表现出竞争抑制作用。这些结果表明,每种NOS同工酶在L-精氨酸结合位点的C-末端附近具有不同大小的腔,并且抑制剂的选择性是由于腔大小的差异而引起的。