12,13-Deoxyepothilone B, EpoA; (4S,7R,8S,9S,13Z,16S)-4,8-Dihydroxy-5,5,7,9,13-pentamethyl-16-[(1E)-1-methyl-2-(2-methyl-4-thiazolyl)ethenyl]oxacyclohexadec-13-ene-2,6-dione; (-)-Desoxyepothilone B; (-)-Epothilone D; KOS 862

Epothilones are polyketid. Potent microtubule stabilizer. Epothilone D is a more potent microtubule stabilizer in vitro than epothilone A or B. In vitro, Epothilone D showed potent cytotoxicity in a panel of human tumor cell lines, with similar potency to paclitaxel. It also showed definite advantage over paclitaxel in drug-resistant cell lines, and retained its cytotoxicity against a multidrug resistant cell line over-expressing P-glycoprotein.