Collimonins A–D, Unstable Polyynes with Antifungal or Pigmentation Activities from the Fungus-Feeding Bacterium Collimonas fungivorans Ter331

The isolation and structure elucidation of collimonins A–D (1–4) from the fungus-feeding bacterium Collimonas fungivorans Ter331 are reported. Collimonins are new derivatives of polyoxygenated hexadecanoic acid, including an ene–triyne moiety. Their absolute configurations were fully determined by combining spectroscopic, chemical, and crystalline sponge methods. Collimonins showed antifungal or pigmentation activities against the fungus Aspergillus niger ATCC 9029.