A continued phytochemical investigation guided by H NMR and LC-MS data on the ethanol extract from the peeled stems of Hemsl. led to the isolation of 16 undescribed dimeric eremophilane sesquiterpenoids, namely syringenes R–Z (–) and A–G (–). These structures were elucidated by extensive analysis of spectroscopic data, including HRESIMS, NMR, quantum-mechanics-based computational analysis of NMR chemical shifts, and single-crystal X-ray diffraction analyses, and a concise rule for determination of relative configuration of angular methyl was proposed. The results of the cardioprotective assay demonstrated that exhibits a protective effect against hypoxia-induced injuries in H9c2 cells. This effect was observed at a concentration of 10 μM, with a protective rate of 28.43 ± 11.80%.

中文翻译：

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紫丁香去皮茎中的二聚eremophilane型倍半萜类化合物

以 H NMR 和 LC-MS 数据为指导，对 Hemsl 去皮茎的乙醇提取物进行了持续的植物化学研究。导致分离出 16 种未描述的二聚 eremophilane 倍半萜类化合物，即注射器 R–Z (–) 和 A–G (–)。这些结构是通过对光谱数据的广泛分析而阐明的，包括 HRESIMS、NMR、基于量子力学的 NMR 化学位移计算分析、单晶 X 射线衍射分析，以及用于确定角甲基相对构型的简明规则被提议。心脏保护测定的结果表明，对 H9c2 细胞缺氧引起的损伤具有保护作用。在浓度为 10 μM 时观察到这种效果，保护率为 28.43 ± 11.80%。