Ansamitocin P-3 Microtubule inhibitor Ansamitocin P-3 is a maytansine analog which displays potent cytotoxicity against the human solid tumor cell lines A-549 and HT-29. It shares the same binding site as rhizoxin and phomopsin A on porcine brain tubulin. Maytansine and its analogs cause extensive disassembly of the microtubule and totally prevent tubulin spiralization. Product Specification Formula: C32H43ClN2O9 MW: 635.1 CAS: 66547-09-9 Purity: ≥93% (HPLC) Appearance: White to off-white crystalline solid. Solubility: Soluble in DMSO. Long Term Storage: -20°C