Department of Marine Chemistry, Faculty of Marine Sciences, King Abdulaziz University , P.O. Box 80207, Jeddah 21589, Saudi Arabia.
Department of Natural Products and Alternative Medicine, Faculty of Pharmacy, King Abdulaziz University , P.O. Box 80260, Jeddah 21589, Saudi Arabia.
J Nat Prod. 2017 Oct 27;80(10):2708-2715. doi: 10.1021/acs.jnatprod.7b00449. Epub 2017 Oct 11.
NMR- and MS-guided fractionation of an extract of an Okeania sp. marine cyanobacterium, collected from the Red Sea, led to the isolation of four new metabolites, including serinolamides C (1) and D (2) and lyngbyabellins O (3) and P (4), together with the three known substances lyngbyabellins F (5) and G (6) and dolastatin 16 (7). The planar structures of the new compounds were determined using NMR and MS analyses. The absolute configurations of 1 and 2 were determined by Marfey's analysis of their hydrolysates. The absolute configuration of 3 was ascertained by chiral-phase chromatography of degradation products, while that of 4 was determined by comparison to 3 and 5. The cytotoxic and antifouling activities of these compounds were evaluated using MCF7 breast cancer cells and Amphibalanus amphitrite larvae, respectively. Compounds 3, 4, and 7 exhibited strong antifouling activity, and 3 and 7 were not cytotoxic. A structure-activity relationship was observed for the cytotoxicity of the lyngbyabellins with the presence of a side chain (4 is more active than 3) leading to greater activity. For the antifouling activity, the acyclic form without a side chain (3) was the most active.
从红海采集的奥克西亚海洋蓝细菌提取物经 NMR 和 MS 引导分离，得到了四个新代谢物，包括丝氨酰胺 C（1）和 D（2）以及石房蛤毒素 O（3）和 P（4），以及三种已知物质石房蛤毒素 F（5）和 G（6）和 dolastatin 16（7）。新化合物的平面结构通过 NMR 和 MS 分析确定。通过对水解产物进行 Marfey 分析确定了 1 和 2 的绝对构型。通过对降解产物进行手性相色谱分析确定了 3 的绝对构型，而 4 的绝对构型则通过与 3 和 5 的比较确定。使用 MCF7 乳腺癌细胞和 Amphibalanus amphitrite 幼虫评估了这些化合物的细胞毒性和抗污活性。化合物 3、4 和 7 表现出强烈的抗污活性，而 3 和 7 没有细胞毒性。观察到石房蛤毒素的细胞毒性与侧链的存在（4 比 3 更活跃）之间存在构效关系。对于抗污活性，无侧链的非环形式（3）最活跃。
