Guangxi Key Laboratory of Bioactive Molecules Research and Evaluation, Pharmaceutical College, Guangxi Medical University, Nanning 530021, China.
Department of Microbial Chemistry, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100050, China.
Mar Drugs. 2023 Feb 23;21(3):143. doi: 10.3390/md21030143.
Mangrove actinomycetia have been proven to be one of the promising sources for discovering novel bioactive natural products. Quinomycins K () and L (), two rare quinomycin-type octadepsipeptides without intra-peptide disulfide or thioacetal bridges, were investigated from the Maowei Sea mangrove-derived sp. B475. Their chemical structures, including the absolute configurations of their amino acids, were elucidated by a combination of NMR and tandem MS analysis, electronic circular dichroism (ECD) calculation, advanced Marfey's method, and further unequivocally confirmed by the first total synthesis. The two compounds displayed no potent antibacterial activity against 37 bacterial pathogens and had no significant cytotoxic activity against H460 lung cancer cells.
从我国海南的一株海洋来源的放线菌 sp. B475 中发现了两个新型的罕见 quinomycin 型八肽化合物 quinomycins K () 和 L ()，它们结构中不含 intra-peptide 二硫键或硫缩醛桥，具有新颖的化学结构。通过 NMR 和串联质谱分析、ECD 计算、Marfey 衍生化分析和全合成验证等方法确定了它们的化学结构，包括氨基酸的绝对构型。这两个化合物对 37 株细菌病原体没有强烈的抗菌活性，对 H460 肺癌细胞也没有显著的细胞毒性。
