Process for the purification of tacrolimus

摘要

A new process for the recovery of tacrolimus in substantially pure form comprising: a) treating an impure or crude tacrolimus with a solvent immiscible with water selected from the group consisting of hydrocarbons, heterocyclic compounds, ethers or esters b) optional concentration of the mixture c) treatment with ammonia gas to remove impurities d) separation of the impurities e) optional concentration of the phase containing tacrolimus, f) load chromatography on silica gel, reverse phase chromatography of silica gel pretreated silica with silver and elution of tacrolimus g) obtaining tacrolimus crystallized or precipitated in substantially pure form.