目的 研究紫玉兰Magnolia liliflora叶中木脂素类化学成分及其抗炎活性。方法 采用硅胶、MCI gel、Sephadex LH-20、半制备HPLC等色谱方法进行分离纯化，根据波谱数据鉴定化合物的结构；通过测定化合物对脂多糖（lipopolysaccharide，LPS）诱导小鼠RAW 264.7巨噬细胞释放炎症介质NO的抑制能力，评价化合物的抗炎活性。结果 从紫玉兰95%乙醇提取物中分离得到16个木脂素，分别鉴定为burcellin（1）、(7S^*,8S^*,1'S^*)-3,4,1'-三甲氧基-1',6'-二氢-7,4'-环氧-8,3'-新木脂烷-8'-烯-6'-酮（2）、(7S^*,8S^*,1'R^*)-3,4,5,1'-四甲氧基-1',6'-二氢-7,4'-环氧-8,3'-新木脂烷-8'-烯-6'-酮（3）、(7S^*,8S^*,1'S^*)-3,4,5,5'-四甲氧基-1',4'-二氢-7,2'-环氧-8,1'-新木脂烷-8'-烯-4'-酮（4）、(7S^*,8S^*,1'R^*)-3,4,5,5'-四甲氧基-1',4'-二氢-7,2'-环氧-8,1'-新木脂烷-8'-烯-4'-酮（5）、(7S^*,8S^*,1'R^*)-3,4,5'-三甲氧基-1',4'-二氢-7,2'-环氧-8,1'-新木脂烷-8'-烯-4'-酮（6）、(7R^*,8S^*,1'S^*)-3,4-亚甲二氧基-5'-甲氧基-1',4'-二氢-7,2'-环氧-8,1'-新木脂烷-8'-烯-4'-酮（7）、simulanol（8）、落叶松树脂醇（9）、5'-甲氧基落叶松树脂醇（10）、5,5'-二甲氧基落叶松树脂醇（11）、nectandrin A（12）、nectandrin B（13）、杜仲树脂酚（14）、丁香脂素（15）和松脂醇（16）。化合物8、10、11、13和16对LPS诱导RAW 264.7细胞释放NO具有显著抑制作用，其半数抑制浓度（median inhibition concentration，IC₅₀）分别为（8.38±0.07）、（16.24±0.35）、（229.71±1.30）、（21.68±0.72）、（19.74±0.39）μmol/L。结论 化合物2、4～6、8、10、11和13为首次从木兰属植物中分离得到；所有化合物均为首次从该植物中分离得到，首次报道化合物1的¹H-和¹³C-NMR数据，并且首次报道化合物2和4的¹³C-NMR数据。化合物8、10、11、13和16具有潜在的抗炎作用。

Objective To study the lignans from Magnolia liliflora and their anti-inflammatory activities. Methods Chemical constituents were separated and purified by column chromatography on silica gel, MCI gel, Sephadex LH-20, and semepreparative HPLC. The structures were characterized via spectroscopic data analysis. All isolated compounds were evaluated their inhibitory activity on lipopolysaccharide (LPS) induced nitric oxide (NO) production in RAW 264.7 macrophages. Results Sixteen compounds were isolated from 95% ethanol extract of M. liliflora. Their structures were identified as burcellin (1), (7S^*,8S^*,1'S^*)-3,4,1'-trimethoxy-1',6'-dihydro-7,4'-epoxy-8,3'-neoligna-8'-en-6'-one (2), (7S^*,8S^*,1'R^*)-3,4,5,1'-tetramethoxy-1',6'- dihydro-7,4'-epoxy-8,3'-neoligna-8'-en-6'-one (3), (7S^*,8S^*,1'S^*)-3,4,5,5'-tetramethoxy-1',4'-dihydro-7,2'-epoxy-8,1'-neoligna-8'-en- 4'-one (4), (7S^*,8S^*,1'R^*)-3,4,5,5'-tetramethoxy-1',4'-dihydro-7,2'-epoxy-8,1'-neoligna-8'-en-4'-one (5), (7R^*,8S^*,1'S^*)-3,4,5'- trimethoxy-1',4'-dihydro-7,2'-epoxy-8,1'-neoligna-8'-en-4'-one (6), (7S^*,8S^*,1'R^*)-3,4-methylenedioxy-5'-methoxy-1',4'-dihydro- 7,2'-epoxy-8,1'-neoligna-8'-en-4'-one (7), simulanol (8), lariciresinol (9), 5'-methoxylariciresinol (10), 5,5'-dimethoxylariciresinol (11), nectandrin A (12), nectandrin B (13), medioresinol (14), syringaresinol (15), pinoresinol (16). Compounds 8, 10, 11, 13, and 16 displayed potent NO inhibitory activities, with IC₅₀ values of (8.38 ±0.07), (16.24 ±0.35), (22.71 ±1.30), (21.68 ±0.72), and (19.74 ±0.39) μmol/L, respectively. Conclusion Compounds 2, 4-6, 8, 10, 11, and 13 are isolated from the genus of Magnolia for the first time. All compounds were obtained from M. liliflora for the first time. The ¹H- and ¹³C-NMR spectroscopic data of 1 was reported for the first time. In addition, the ¹³C-NMR spectroscopic data of 2 and 4 were also reported for the first time. Compounds 8, 10, 11, 13, and 16 indicate their potential anti-inflammatory effects.

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基金项目:云南省科技厅-昆明医科大学应用基础研究联合专项基金资助项目(2019FE001-028);云南省教育厅科学研究基金项目(2021J0876);云南省万人计划"教学名师"(宋流东)资助项目;云南省创新团队(202005AE160004)