Department of Pharmacognosy, College of Pharmacy, Najran University, Najran 55461, Saudi Arabia; Department of Pharmacognosy, Faculty of Pharmacy, Al-Azhar University, Assiut-branch, Assiut 71524, Egypt.
Meikai University Research Institute of Odontology (M-RIO), Sakado, Saitama 350-0283, Japan.
Fitoterapia. 2021 Sep;153:104925. doi: 10.1016/j.fitote.2021.104925. Epub 2021 May 11.
Investigation on tannins having antitumor properties led to the isolation of two new C-glycosidic ellagitannins (1 and 2) along with seven known ellagitannins (3-9) and a related polyphenolic constituent (10) from Lawsonia inermis leaves. Our intensive HRESIMS, 1D and 2D NMR, and ECD spectroscopic studies of new tannins have shown that one (1) has a monomer structure of C-glycosidic tannin, and the other (2) has a dimeric structure of 2,3-O-hexahydroxydiphenoyl glucopyranose and a C-glycosidic tannin. Among the known compounds, one (3) is a C-glycosidic tannin that was isolated first of all from nature, five were C-glycosidic tannins, vescalagin (4), 1-O-methylvescalagin (5), castalagin (6), stachyurin (7), and casuarinin (8), and one was an O-glycosidic ellagitannin, tellimagrandin II (9). The remaining phenolic constituent from the leaves was identified as valoneic acid dilactone (10). The ellagitannins 1, and 3-9 demonstrated noticeable cytotoxicity on human oral squamous cell carcinoma cell lines (HSC-2, HSC-4, and Ca9-22), and lower effects on human oral normal cells (HGF, HPC, and HPLF). Tellimagrandin II (9) had the highest tumor-specific cytotoxicity, and also cleaved poly (ADP-ribose) polymerase 1 in HSC-2 cells. These findings showed that L. inermis ellagitannins may be a candidate for the production of anti-oral cancer materials.
从罗勒叶中分离得到两种新的 C-糖苷鞣花单宁（1 和 2）以及七种已知的鞣花单宁（3-9）和一种相关的多酚成分（10），这些物质具有抗肿瘤特性。通过对新鞣质的高强度 ESI 质谱、1D 和 2D NMR 和 ECD 光谱研究表明，其中一个（1）具有 C-糖苷单宁的单体结构，另一个（2）具有 2,3-O-六氢二苯甲酰基葡萄糖和 C-糖苷单宁的二聚体结构。在已知的化合物中，一个（3）是首次从自然界中分离得到的 C-糖苷单宁，有五个是 C-糖苷单宁，分别是鞣花丹宁（4）、1-O-甲基鞣花丹宁（5）、苛伐鞣灵（6）、鞣云实精（7）和黄杉素（8），还有一个是 O-糖苷鞣花单宁，三叶豆杉素 II（9）。来自叶片的剩余酚类成分被鉴定为缬草酸二内酯（10）。鞣花单宁 1 和 3-9 对人口腔鳞状细胞癌细胞系（HSC-2、HSC-4 和 Ca9-22）表现出明显的细胞毒性，对人口腔正常细胞（HGF、HPC 和 HPLF）的影响较小。三叶豆杉素 II（9）具有最高的肿瘤特异性细胞毒性，并且还能在 HSC-2 细胞中切割聚（ADP-核糖）聚合酶 1。这些发现表明罗勒叶鞣花单宁可能是生产抗口腔癌材料的候选物。
