Thirteen new ent-kaurane diterpenoids, stigmaydenes A–M (1-13), together with two known compounds (14, 15), were isolated from the crude extract of corn silk (Zea mays). The structures of the compounds were confirmed by comprehensive spectroscopic analyses. The absolute configuration of compound 1 was defined by single-crystal X-ray diffraction. The absolute configurations of the compounds were also confirmed by comparison of experimental and calculated specific rotations. The compounds were evaluated for their neuroprotective effects against H₂O₂-induced SH-SY5Y cell injury, and compound 8 was active at 100 μM, as determined by flow cytometry (annexin V-FITC/PI staining) and Hoechst 33258 staining. The results suggested that compound 8 could protect neuronal cells from H₂O₂-induced injury by inhibiting apoptosis in SH-SY5Y cells.

中文翻译：

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耳鼻喉科-Kaurane二萜与玉米须神经保护特性（玉米）

13个新的ENT -kaurane二萜类化合物，stigmaydenes A-M（1 - 13），加上两个已知化合物（14，15），从玉米丝的粗提取物中分离（玉蜀黍）。通过全面的光谱分析证实了化合物的结构。化合物1的绝对构型通过单晶X射线衍射确定。通过比较实验和计算的比旋光度也证实了化合物的绝对构型。评估了化合物对H ₂ O ₂诱导的SH-SY5Y细胞损伤的神经保护作用，以及化合物8通过流式细胞仪（annexin V-FITC / PI染色）和Hoechst 33258染色确定，其在100μM时具有活性。结果表明，化合物8可以通过抑制SH-SY5Y细胞的凋亡来保护神经元细胞免受H ₂ O ₂诱导的损伤。