Isolation, purification, synthesis, and antiinvasive/antimetastatic activity of U-77863 and U-77864 from Streptomyces griseoluteus, strain WS6724.

In screening of actinomycetes for structures with differential solid tumor activity, Streptomyces griseoluteus, strain WS6724 was found to produce U-77863 and U-77864. U-77863 exhibited antiinvasive activity in vitro in the membrane invasion culture system (MICS) and a dose-dependent antimetastatic activity in vivo versus K1735-M2 and B16-F10 murine melanomas. The isolation, purification, and synthesis of both structures and biological activity is reported.