Peng Weiwei, Huang Qi, Ke Xin, Wang Wenxuan, Chen Yan, Sang Zihuan, Chen Chen, Qin Siyu, Zheng Yuting, Tan Haibo, Zou Zhenxing
Xiangya School of Pharmaceutical Sciences, Hunan Key Laboratory of Diagnostic and Therapeutic Drug Research for Chronic Diseases, Central South University, Changsha, 410013, People's Republic of China.
Key Laboratory of National Forestry and Grassland Administration on Plant Conservation and Utilization in Southern China, State Key Laboratory of Plant Diversity and Specialty Crops, Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic Improvement, Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, 510650, People's Republic of China.
Nat Prod Bioprospect. 2024 Jan 11;14(1):8. doi: 10.1007/s13659-024-00429-z.
Two novel koninginin derivatives, koningipyridines A and B (1 and 2), along with four known compounds (3-6) were isolated from the EtOAc extract of the endophytic fungus Trichoderma koningiopsis SC-5. Among them, koningipyridine A featured an unprecedented pentacyclic ketal skeleton with the formation of a fascinating 6/6/5/6/5 fused ring system and shared a characteristic pyridine core, which represents the first example of nitrogen-containing koninginin-type natural product. Moreover, koningipyridine B was the first member in the koninginin family sharing a unique 6/6/5 dihydropyridine skeleton, and it was suggested to be the critical biosynthetic precursor of koningipyridine A. The structures of 1 and 2 were elucidated by the interpretation of 1D and 2D NMR spectroscopy, HRESIMS data, as well as theoretical calculations of C NMR and electronic circular dichroism (ECD). Moreover, all isolates were screened for antimicrobial activities against Staphylococcus aureus, MRSA, and Escherichia coli as well as the cytotoxic effects against three cancer cell lines (A549, Hela, and HepG2).
从内生真菌康宁木霉SC-5的乙酸乙酯提取物中分离得到两种新型的康宁菌素衍生物，即康宁吡啶A和B（1和2），以及四种已知化合物（3-6）。其中，康宁吡啶A具有前所未有的五环缩酮骨架，形成了一个引人入胜的6/6/5/6/5稠环体系，并具有一个特征性的吡啶核心，这代表了含氮康宁菌素型天然产物的首个实例。此外，康宁吡啶B是康宁菌素家族中首个具有独特的6/6/5二氢吡啶骨架的成员，被认为是康宁吡啶A的关键生物合成前体。通过一维和二维核磁共振光谱、高分辨电喷雾电离质谱数据以及碳核磁共振和电子圆二色光谱（ECD）的理论计算，阐明了1和2的结构。此外，对所有分离物进行了针对金黄色葡萄球菌、耐甲氧西林金黄色葡萄球菌和大肠杆菌的抗菌活性以及对三种癌细胞系（A549、Hela和HepG2）的细胞毒性作用筛选。
