A substance being studied in the treatment of cancer. It is a type of mitotic inhibitor and epothilone. Also called KOS-862. OR A natural polyketide compound isolated from the myxobacterium Sorangium cellulosum. Also known as desoxyepothilone B, epothilone D binds to tubulin and inhibits the disassembly of microtubules, resulting in the inhibition of mitosis, cellular proliferation, and cell motility.