2-methoxyestradiol having greater than 98% purity is obtained by synthetic or purification methods. This highly pure 2-methoxy estradiol, lacking estrogenic components, is particularly suitable for clinical use in humans. The purification methods of the invention involve the use of liquid-solid chromatography (LSC) to separate 2-ME2 from other compounds. The chromatographic media is preferably silica. The solvent system comprises a non-polar solvent, such as chloroform, and a polar solvent, such as methanol.