Institute of Traditional Chinese Medicine & Natural Products, College of Pharmacy/Guangdong Province Key Laboratory of Pharmacodynamic Constituents of TCM and New Drugs Research, Jinan University, Guangzhou 510632, People's Republic of China; College of Traditional Chinese Materia Medica, Shenyang Pharmaceutical University, Shenyang 110016, People's Republic of China.
Institute of Traditional Chinese Medicine & Natural Products, College of Pharmacy/Guangdong Province Key Laboratory of Pharmacodynamic Constituents of TCM and New Drugs Research, Jinan University, Guangzhou 510632, People's Republic of China.
Bioorg Chem. 2020 Aug;101:104043. doi: 10.1016/j.bioorg.2020.104043. Epub 2020 Jun 25.
Nine new N-methoxy-β-carboline alkaloids (NMCAs) (1a/1b-3a/3b and 4-6) and two known NMCAs (7 and 8) were isolated from the stems of Picrasma quassioides. Their structures were elucidated by spectroscopic data analyses, quantum chemical calculations, and single-crystal X-ray crystallographic data. An analysis of the C NMR chemical shifts of the N-methoxy groups in these NMCAs and 41 gathered known compounds reveals the phenomenon that the chemical shifts of all these N-methoxy groups are greater than δ 62, which can be used to recognize the N-methoxy group rapidly. In addition, the acetylcholinesterase (AChE) and Aβ aggregation inhibitory activities of 1-8 were evaluated. Compounds 1, 2, 7, and 8 displayed AChE inhibitory activity with IC values of 14.9, 13.2, 17.6, and 43.9 μM, respectively. Compound 2 showed inhibition activity against Aβ aggregation with an IC value of 10.1 μM.
从白皮树的茎中分离得到了 9 种新的 N-甲氧基-β-咔啉生物碱（NMCAs）（1a/1b-3a/3b 和 4-6）和 2 种已知的 NMCAs（7 和 8）。通过光谱数据分析、量子化学计算和单晶 X 射线晶体学数据阐明了它们的结构。对这些 NMCAs 和 41 种已知化合物的 N-甲氧基的 13C NMR 化学位移分析表明，所有这些 N-甲氧基的化学位移均大于δ62，可以用于快速识别 N-甲氧基。此外，还评估了 1-8 对乙酰胆碱酯酶（AChE）和 Aβ 聚集的抑制活性。化合物 1、2、7 和 8 对 AChE 的抑制活性的 IC 值分别为 14.9、13.2、17.6 和 43.9μM。化合物 2 对 Aβ 聚集的抑制活性的 IC 值为 10.1μM。
