Aristolochic alkaloids from Piper macropodum and their anti-inflammatory activities

Five aristolochic lactam alkaloids (1-5), including two new ones (1-2), along with two new natural products (6- 7) were isolated from Piper macropodum. The structures of the new compounds (1-2) were elucidated by extensive spectroscopic analysis. The structures of compounds (3-7) were identified on the basis of NMR spectroscopic data analyses and comparison with the data reported in literature. Consequently, compounds 1-5 showed good inhibitory effects on NO releasing from RAW264.7 cells induced by LPS.

Automated summary

Two new compounds were isolated from Piper macropodum and their structures were determined through extensive spectroscopic analysis. The structures of the remaining compounds were identified by comparing NMR spectroscopic data with literature reports. The compounds exhibited significant inhibitory effects on NO release from LPS-induced RAW264.7 cells.