Fifteen new peptide derivatives of ɛ-aminocaproic acid (EACA) containing the known fragment –Ala–Phe–Lys– with an affinity for plasmin were synthesised in the present study. The synthesis was carried out a solid phase. The following compounds were synthesised: H–Phe–Lys–EACA–X, H–d-Ala–Phe–Lys–EACA–X, H–Ala–Phe–Lys–EACA–X, H–d-Ala–Phe–EACA–X and H–Ala–Phe–EACA–X, where X = OH, NH₂ and NH–(CH₂)₅–NH₂. All peptides, except for those containing the sequence H–Ala–Phe–EACA–X, displayed higher inhibitory activity against plasmin than EACA. The most active and selective inhibitor of plasmin was the compound H–d-Ala–Phe–Lys–EACA–NH₂ which inhibited the amidolytic activity of plasmin (IC₅₀ = 0.02 mM), with the antifibrinolytic activity weaker than EACA. The resulting peptides did not affect the viability of fibroblast cells, colon cancer cell line DLD-1, breast MCF-7 and MDA-MB-231 cell lines.

中文翻译：

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具有6-氨基己酸的肽：纤溶酶抑制剂的合成和评估。

在本研究中，合成了15种新的γ-氨基己酸（EACA）肽衍生物，其中包含已知片段–Ala–Phe–Lys–对纤溶酶具有亲和力。合成进行固相。合成了以下化合物：H–Phe–Lys–EACA–X，H – d -Ala–Phe–Lys–EACA–X，H–Ala–Phe–Lys–EACA–X，H – d -Ala–Phe– EACA–X和H–Ala–Phe–EACA–X，其中X = OH，NH ₂和NH–（CH ₂）₅ –NH ₂。除含有H–Ala–Phe–EACA–X序列的肽外，所有肽对纤溶酶的抑制活性均高于EACA。纤溶酶最活跃，选择性最高的抑制剂是化合物H– d –Ala–Phe–Lys–EACA–NH ₂抑制纤溶酶的酰胺分解活性（IC ₅₀  = 0.02 mM），抗纤溶活性比EACA弱。所得肽不影响成纤维细胞，结肠癌细胞系DL D -1，乳腺MCF-7和MDA-MB-231细胞系的活力。