Natural Sciences and Science Education, National Institute of Education, Nanyang Technological University, 1 Nanyang Walk, Singapore 637616, Singapore.
Phytochemistry. 2010 Feb;71(2-3):307-11. doi: 10.1016/j.phytochem.2009.10.006. Epub 2009 Nov 11.
Hantupeptins B (2) and C (3) were isolated, along with the previously reported hantupeptin A (1), from the marine cyanobacterium, Lyngbya majuscula, collected from Pulau Hantu Besar, Singapore. Their structures were elucidated by interpretation of extensive 1D and 2D NMR spectroscopic data. Compounds 2 and 3 are cyclic depsipeptides consisting of five alpha-amino/hydroxy acid residues, including phenyllactic acid, proline, N-methyl-valine, valine, N-methyl-isoleucine, and a beta-hydroxy acid unit with different degrees of unsaturation at the terminal end of each molecule. The absolute configurations of the common amino acids and phenyllactic acid were determined by the advanced Marfey's and chiral HPLC analyses, respectively. The complete stereochemistry of 3-hydroxy-2-methyl-7-octynoic acid moiety in hantupeptin A was elucidated by a combination of homonuclear J-resolved 2D NMR experiments and by Mosher's method. Hantupeptins B and C showed moderate in vitro cytotoxicity when tested against MOLT-4 (leukemic) and MCF-7 (breast cancer) cell lines.
从新加坡大虎屿采集的海洋蓝藻 Lyngbya majuscula 中分离得到了 Hantupeptins B (2) 和 C (3)，以及之前报道的 Hantupeptin A (1)。通过对广泛的 1D 和 2D NMR 光谱数据的解释，确定了它们的结构。化合物 2 和 3 是由五个 α-氨基酸/羟基酸残基组成的环状 depsipeptides，包括苯乳酸、脯氨酸、N-甲基缬氨酸、缬氨酸、N-甲基异亮氨酸和一个β-羟基酸单元，每个分子的末端具有不同程度的不饱和。通过先进的 Marfey's 和手性 HPLC 分析，分别确定了常见氨基酸和苯乳酸的绝对构型。通过同核 J 分辨 2D NMR 实验和 Mosher 法的组合，阐明了 Hantupeptin A 中 3-羟基-2-甲基-7-辛炔酸部分的完整立体化学。当测试对 MOLT-4（白血病）和 MCF-7（乳腺癌）细胞系的体外细胞毒性时，Hantupeptins B 和 C 表现出中等的活性。
