Tripeptides of the general X-SO₂-d-Ser-AA-Arg-CO-Y formula, where X = α-tolyl, p-tolyl, 2,4,6-triisopropylphenyl; AA = alanine, glycine, norvaline and Y = OH, NH-(CH₂)₅NH₂ were obtained and tested for their effect on the amidolytic activities of urokinase, thrombin, trypsin, plasmin, t-PA and kallikrein. The most active compound towards urokinase was PhCH₂SO₂-d-Ser-Gly-Arg-OH with K_i value 5.4 μM and the most active compound toward thrombin was PhCH₂SO₂-d-Ser-NVa-Arg-OH with K_i value 0.82 μM. The peptides were nontoxic against porcine erythrocytes in vitro. PhCH₂SO₂-d-Ser-Gly-Arg-OH showed cytotoxic effect against DLD cell lines with IC₅₀ values of 5 μM. For the highly selective determination of the interaction of some of the synthesised acids of tripeptides with urokinase and plasmin the Surface Plasmon Resonance Imaging sensor has been applied. These compounds bind to urokinase and plasmin in 0.05 mM concentration.

中文翻译：

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以 C 端精氨酸作为潜在丝氨酸蛋白酶抑制剂的 N-磺酰三肽的合成和生物活性。

X-SO ₂ - d -Ser-AA-Arg-CO-Y 通式的三肽，其中 X =  α -甲苯基、对甲苯基、2,4,6-三异丙基苯基；获得AA = 丙氨酸、甘氨酸、正缬氨酸和Y = OH、NH-(CH ₂ ) ₅ NH ₂并测试它们对尿激酶、凝血酶、胰蛋白酶、纤溶酶、t-PA 和激肽释放酶的酰胺分解活性的影响。对尿激酶最活跃的化合物是 PhCH ₂ SO ₂ - d -Ser-Gly-Arg-OH，K _i值为 5.4 μM，对凝血酶最活跃的化合物是 PhCH ₂ SO ₂ - d -Ser-NVa-Arg-OH钾_i值为 0.82 μM。这些肽在体外对猪红细胞无毒。PhCH ₂ SO ₂ - d -Ser-Gly-Arg-OH 显示出对 DLD 细胞系的细胞毒性作用，IC ₅₀值为 5 μM。为了高度选择性地测定某些合成的三肽酸与尿激酶和纤溶酶的相互作用，已应用表面等离子体共振成像传感器。这些化合物以 0.05 mM 的浓度与尿激酶和纤溶酶结合。