Eight previously undescribed isoquinoline alkaloids, mucroniferanines H-M, together with 16 known isoquinoline alkaloids, were isolated from Corydalis mucronifera Maxim.. The structures of the previously undescribed compounds were elucidated by interpretation of 1D and 2D NMR spectroscopic and HRMS data, and their absolute configurations were established by computational electronic circular dichroism (ECD) calculations and X-ray diffraction data. Mucroniferanine L is reported as the first natural amide bond linked isoquinoline alkaloid dimer. The isolated compounds were evaluated for AChE and BuChE inhibitory activities and mucroniferanine H showed significant activities with IC50 values of 2.31 μM and 36.71 μM, respectively.

中文翻译：

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来自 Corydalis mucronifera 的胆碱酯酶抑制异喹啉生物碱

从 Corydalis mucronifera Maxim 中分离出 8 种以前未描述的异喹啉类生物碱 mucroniferanine HM 以及 16 种已知的异喹啉类生物碱。 通过对 1D 和 2D NMR 光谱和 HRMS 数据的解释阐明了以前未描述的化合物的结构，并且它们的绝对构型为通过计算电子圆二色性 (ECD) 计算和 X 射线衍射数据建立。据报道，Mucroniferanine L 是第一个天然酰胺键连接的异喹啉生物碱二聚体。评估了分离的化合物的 AChE 和 BuChE 抑制活性，并且 mucroniferanine H 显示出显着的活性，IC50 值分别为 2.31 μM 和 36.71 μM。