Koshikamide B, a cytotoxic peptide lactone from a marine sponge Theonella sp
Koshikamide B, a cytotoxic peptide lactone from a marine sponge Theonella sp
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DOI：
10.1021/jo801032n
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发表时间：
2008-10-17
影响因子：
3.6
通讯作者：
Fusetani, Nobuhiro
中科院分区：
文献类型：
--
作者：
Araki, Takahiro;Matsunaga, Shigeki;Fusetani, Nobuhiro
Koshikamide B (1) 已从海洋海绵 Theonella sp. 的两个不同收藏品中分离出来。作为主要的细胞毒性成分。 Koshikamide B 是一种 17 个残基的肽内酯，由 6 个蛋白氨基酸、2 个蛋白氨基酸 D 异构体、7 个 N-甲基化氨基酸和 2 个异常氨基酸残基组成。不常见的氨基酸是 N-δ-氨基甲酰天冬酰胺和 2-(3-氨基-2-羟基-5-氧代吡咯烷-2-基)丙酸 (AHPP)；前者首先作为肽的组成部分被发现，而后者是新的氨基酸残基。 koshikamide B 的 N 末端被甲氧基乙酰基封闭。通过光谱数据的解释和化学降解产物的分析，确定了 koshikamide B (1) 的结构。 Koshikamide B (1) 对 P388 小鼠白血病细胞和人结肠肿瘤 (HCT-116) 细胞系表现出细胞毒性，IC50 值分别为 0.45 和 7.5 μg/mL。
Koshikamide B (1) has been isolated from two separate collections of the marine sponge Theonella sp. as the major cytotoxic constituent. Koshikamide B is a 17-residue peptide lactone composed of six proteinogenic amino acids, two D-isomers of proteinogenic amino acids, seven N-methylated amino acids, and two unusual amino acid residues. The unusual amino acids are N-delta-carbamoylasparagine and 2-(3-amino-2-hydroxy-5-oxopyrrolidin-2-yl)propionic acid (AHPP); the former is first found as the constituent of peptides, whereas the latter is a new amino acid residue. The N-terminus of koshikamide B is blocked by a methoxyacetyl group. The structure of koshikamide B (1) has been determined by interpretation of spectral data and analysis of chemical degradation products. Koshikamide B (1) exhibits cytotoxicity against P388 murine leukemia cells and the human colon tumor (HCT-116) cell line with an IC50 value of 0.45 and 7.5 mu g/mL, respectively.