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Published on: September 28, 2022
Immune-inhibitive phenyl-C1 substituent aporphine alkaloids from Thalictrum cirrhosum
Zi-Ru Yan1, Zeng-Yuan Wang2, Bei Wang3
1State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China.
Abstract:
Five new phenyl-C1 substituent aporphine alkaloids, 6aR-2'-methoxycarbonyl-thaliadin (1), 6aR-2'-carboxyl-thaliadin (2), 6aR-3-methoxy-hernandalinol (3), 6aS-1,3,10-trimethoxy-natalamine (4), and 3-methoxy-2'-methoxycarbonyl-oxohernandalincin (5), together with sixteen known isoquinoline alkaloids (6-21) were isolated from the whole herb of Thalictrum cirrhosum (Levl.). Their structures were elucidated by extensive spectroscopic measurements, and six isoquinoline alkaloids showed significant inhibitory activity on concanavalin A-stimulated splenocytes proliferation with IC50 values 36-44 μM by the immunosuppressive bioassay.
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