New Alpiniamide‐Type Polyketide with Antibiofilm Activities from the Marine‐Derived Streptomyces sp. ZS‐A65

Abstract Two new alpiniamide‐type polyketides, alpiniamides H−I ( 1 ‐ 2 ), in addition to four recognized compounds, were discovered in Streptomyces sp. ZSA65 derived from the marine sediments. The planar structure and absolute configuration of alpiniamides H−I were elucidated using a combination of 1D, 2D NMR, HRESIMS data analysis, Mosher's method and ECD calculations. The antibiofilm and antibacterial activities against P. aeruginosa were evaluated using the microdilution method. Notably, Compound 2 exhibited strong antibiofilm property.