A third-generation epothilone B analogue with potential anti-mitotic and antineoplastic activites. Iso-fludelone binds to tubulin and induces microtubule polymerization and stabilizes microtubules against depolymerization, which may result in the inhibition of cell division, the induction of G2/M arrest, and apoptosis. Compared to other generations of epothilones, iso-fludelone exhibits increased stability, water solubility, potency, duration of action, tumor penetration as well as reduced toxicity. In addition, this agent is a not a substrate of the P-glycoprotein (P-gp), a multidrug resistance pump often overexpressed in cancer cells. [ ]