Abstract: The present invention relates to a process of preparing a highly pure tacrolimus, which comprising a pre-purification process carried out by means of crystallization, and particularly to a process of preparing a highly pure tacrolimus, which comprises a pre-purification process comprising the steps of (a) extracting mycelia cake collected by filtering a tacrolimus-containing oily compound with an organic solvent, (b) concentrating the extract under reduced pressure and (c) crystallizing the concentrate. In addition, a highly pure tacrolimus can be obtained by dissolving the pre-purified crystals in an organic solvent, passing through the solution in an adsorption resin and concentrating the eluate under reduced pressure, followed by crystallization. According to a process of the present invention, Tacrolimus as pure as appropriate for a pharmaceutical purpose can be prepared by a simple process and at a relatively low cost.

Abstract: The present invention relates to a process of preparing a highly pure tacrolimus, which comprising a pre-purification process carried out by means of crystallization, and particularly to a process of preparing a highly pure tacrolimus, which comprises a pre-purification process comprising the steps of (a) extracting mycelia cake collected by filtering a tacrolimus-containing oily compound with an organic solvent, (b) concentrating the extract under reduced pressure and (c) crystallizing the concentrate. In addition, a highly pure tacrolimus can be obtained by dissolving the pre-purified crystals in an organic solvent, passing through the solution in an adsorption resin and concentrating the eluate under reduced pressure, followed by crystallization. According to a process of the present invention, Tacrolimus as pure as appropriate for a pharmaceutical purpose can be prepared by a simple process and at a relatively low cost.