Abstract
Leptolstatin, a product from Streptomyces sp. SAM 1595, is a gap phase-specific inhibitor of the mammalian cell cycle. Physico-chemical properties and spectrometric analyses showed that the structure of leptolstatin is (2Z, 6E, 8Z, 12E, 14E, 22E)-19, 24-dihydroxy-8, 10, 14, 16, 18, 20, 22-heptamethyl-17-oxo-2, 6, 8, 12, 14, 22-tetracosahexaen-5-olide.