The establishment of the control substance and ¹H nuclear magnetic resonance fingerprint of Macleaya microcarpa (Maxim.) Fedde

The control substance of plant drugs (CSPDs) and their ¹H nuclear magnetic resonance (NMR) spectra for six samples of Macleaya microcarpa (Maxim.) Fedde collected from different regions were obtained by standard procedure. Six pure compounds were isolated from the CSPD of this plant and their structures were elucidated as dihydrosanguinarine (1), dihydrochelerythrine (2), 6-methoxydihydrosanguinarine (3), 6- methoxydihydrochelerythrine (4), oleanolic acid (5) and protopine (6), respectively, on the basis of spectroscopic techniques. The characteristic signals in the ¹H NMR fingerprints of CSPDs of M. microcarpa were assigned by the comparative analysis of the ¹H NMR spectra of CSPDs and these pure compounds. It can be revealed that the ¹H NMR fingerprints of the samples of M. microcarpa. collected from different regions have highly characteristic features and reproducibility, and shows mainly the characteristic signals of the above alkaloids. They can be utilized for the original authentication of this plant species.