Key Laboratory of Plant Resources Conservation and Sustainable Utilization/Guangdong Provincial Key Laboratory of Digital Botanical Garden, South China Botanical Garden, Chinese Academy of Sciences, Xingke Road 723, Tianhe District, Guangzhou 510650, People's Republic of China.
J Nat Prod. 2020 May 22;83(5):1480-1487. doi: 10.1021/acs.jnatprod.9b01071. Epub 2020 Apr 15.
Eight new polyhydroxanthones, penicixanthones A-H (-), including four monomers (-) and four dimers (-), were isolated from solid cultures of SC0070. Their structures were elucidated by extensive spectroscopic analysis, X-ray single-crystal diffraction, and theoretical computations of ECD spectra. Penicixanthone B () has a hexahydroxanthone structure featuring an unusual oxygen bridge between C-6 and C-8a. Penicixanthone D () is distinct from other penicixanthones in stereochemistry, and its biosynthetic mechanism was proposed based on theoretical simulations for the reaction pathway of C-10a epimerization. Penicixanthone G () exhibited the most potent cytotoxicity (IC: 0.3-0.6 μM) when tested against human carcinoma A549, HeLa, and HepG2 cells, whereas it was nontoxic to the normal Vero cells (IC > 50 μM). It also displayed the strongest antibacterial activity (MIC: 0.4 μg/mL) against both and the methicillin-resistant strain MRSA.
从 SC0070 的固体培养物中分离得到了 8 个新的多羟基呫吨酮，包括 4 个单体（-）和 4 个二聚体（-）。通过广泛的光谱分析、X 射线单晶衍射和 ECD 光谱的理论计算，阐明了它们的结构。Penicixanthone B () 具有六羟基呫吨酮结构，其 C-6 和 C-8a 之间存在不寻常的氧桥。Penicixanthone D () 在立体化学上与其他呫吨酮不同，根据 C-10a 差向异构化反应途径的理论模拟，提出了其生物合成机制。Penicixanthone G () 在对人癌细胞 A549、HeLa 和 HepG2 细胞的测试中表现出最强的细胞毒性（IC：0.3-0.6 μM），而对正常的 Vero 细胞（IC > 50 μM）则没有毒性。它还对 和耐甲氧西林的 MRSA 菌株表现出最强的抗菌活性（MIC：0.4 μg/mL）。
