Fig. 6.

Structure of mycolactones F and dia-F isolated from M. marinum DL240490 (cultured European sea bass) and BB170200 (freshwater silver perch), respectively. For the structure of core, see Fig. 5. Under the photochemical condition (300 nm, acetone), both mycolactones smoothly isomerize, to furnish a 5∶2∶2 mixture of three predominant regioisomers. A wavy line indicates that this bond exists as a mixture of E- and Z-geometrical isomers.