Lodopyridones D − G from a marine-derived bacterium Saccharomonospora sp.

The intensive investigation of chemical components from the culture broth of the bacterium Saccharomonospora sp. CNQ-490 has yielded four new natural products, lodopyridones D − G (1 − 4) along with the previously reported compounds, lodopyridones A − C (5 − 7) and cotteslosin A (8). The planar structures of the lodopyridones D − G (1 − 4) were elucidated by interpreting the mass spectrometry, ultraviolet (UV) spectroscopy, and 1D and 2D nuclear magnetic spectroscopy (NMR) data, as well as comparing NMR data with those of the lodopyridones A − C (5 − 7).</p