Isolation of Lomaiviticins C–E, Transformation of Lomaiviticin C to Lomaiviticin A, Complete Structure Elucidation of Lomaiviticin A, and Structure–Activity Analyses

We describe the isolation of (–)-lomaiviticins C–E (6–8), elucidation of the complete absolute and relative stereochemistry of (–)-lomaiviticin A (1), the synthetic conversion of (–)-lomaiviticin C (6) to (–)-lomaiviticin A (1), and the first evidence that the dimeric diazofluorene of (–)-lomaiviticin A (1) plays a defining and critical role in antiproliferative activity.