抄録
During the course of screening for novel cell cycle inhibitors, FRl 82877 was isolated from the fermentation broth of Streptomyces sp. No.9885. During the NMR measurements, FRl 82877 decomposed so much that the structure elucidation of FRl 82877 itself was difficult. Then, combinations of chemical correlations and spectroscopic methods clarified that FRl 82877 possesses an unprecedented multi-ring system including the strained double bond, which was unexpectedly epoxidized by molecular oxygen. FRl 82877 showed broad antitumor activities in vitro and promoted assemblies of tublins in vitro as well as taxol. It is noteworthy that epoxidation of the distorted double bond resulted in significant decrease in antitumor activities.
