Amide alkaloids from Piper polysyphorum and their antifungal activities.

Eight new amide alkaloids, named piperpolyactam A (1) and piperpolyamide A-G (2-8), along with thirty known ones (9-38) were isolated from the extract of piper polysyphorum. Their structures were elucidated by extensive spectroscopic analyses (including 1D, 2D-NMR and HRESIMS). Compounds 1-38 were assessed for antifungal activity against Candida albicans CMCC 98001 and Aspergillus niger R330. Compound 36 showed a significant antifungal effect against A. niger R330, with the MIC value of 0.78 μg/mL.