[Two new alkaloids from Corydalis delicatula]

In this study, the total alkaloids of Corydalis delicatula were isolated and purified by a combination of silica gel, aluminum oxide basic column chromatography and other chromatographic techniques. The obtained compounds were structurally identified with the help of modern spectral resolution techniques such as nuclear magnetic resonance(1D/2D NMR), high-resolution mass spectrometry(HR-ESI-MS), and single crystal X-ray diffraction. Nine alkaloids were obtained from the total alkaloids of C. delicatula, encompassing two new compounds, corlicatine(1) and N-methyl-13-oxoprotopine(2), and seven known ones:(+)-ochotensine(3), rupestrine A(4),(+)-ochotensimine(5), oxohydrastinine(6), α-magnoflorine(7), 6,7-methylenedioxy-N-methylisoquinoline(8), and N-methyl-6,7-dimethoxyisoquinoline(9). The inhibitory activities of the compounds against acetylcholinesterase were evaluated, with compound 4 exhibiting moderate inhibition. Molecular docking was further performed to elucidate the binding mode of this compound. The results provide a basis for elucidating the medicinal substance basis of C. delicatula.