Five undescribed phenolics named pithecellobiumin C-G, along with thirteen known ones were isolated from the twigs and leaves of Archidendron clypearia (Jack) I.C.Nielsen. Their structures were elucidated based on comprehensive spectroscopic analyses, combined with computer-assisted structure elucidation software (ACD/Structure Elucidator) and gauge-independent atomic orbitals (GIAO) NMR chemical shift calculations. The absolute configurations were determined by comparison of experimental and calculated specific rotation and ECD curves. These compounds were tested for their neuroprotective activities against H2O2-induced injury in human neuroblastoma SH-SY5Y cells by MTT assay. Pithecellobiumin C-E exhibited noticeable neuroprotective effect. Further pharmacological study demonstrated that they could prevent cell death through inhibiting the apoptosis induction. Flow cytometry assays also proved that these compounds could attenuate reactive oxygen species (ROS) level and mitochondrial dysfunction in SH-SY5Y cells.

中文翻译：

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来自 Archidendron clypearia (Jack) ICNielsen 的酚类物质保护 SH-SY5Y 细胞免受 H2O2 诱导的氧化应激

从 Archidendron clypearia (Jack) ICNielsen 的树枝和叶子中分离出五种未描述的酚类物质，名为 pithecellobiumin CG，以及 13 种已知的酚类物质。基于综合光谱分析，结合计算机辅助结构解析软件（ACD/Structure Elucidator）和规范无关原子轨道（GIAO）核磁共振化学位移计算，阐明了它们的结构。绝对构型是通过比较实验和计算的比旋转和 ECD 曲线来确定的。通过 MTT 法测试这些化合物对 H2O2 诱导的人神经母细胞瘤 SH-SY5Y 细胞损伤的神经保护活性。Pithecellobiumin CE 表现出明显的神经保护作用。进一步的药理研究表明，它们可以通过抑制细胞凋亡诱导来防止细胞死亡。流式细胞术分析还证明，这些化合物可以减弱 SH-SY5Y 细胞中的活性氧 (ROS) 水平和线粒体功能障碍。