THE SELECTIVELY CRYSTALLIZING METHOD OF HEMIPENTAHYDRATE OF RISEDRONATE SODIUM SALT

摘要

A method for crystallizing hemipentahydrate of a risedronate sodium salt is provided to crystallize the hemipentahydrate of a risedronate more simply and selectively by removing the possibility of chemistry shock or heat shock regarding a crystallization system through controlling solvent composition and temperature of nucleation and crystal growth. A method for crystallizing hemipentahydrate of a risedronate sodium salt selectively comprises the steps of: (a) providing a mixture solvent of a hydrophilic organic solvent such as ketone and ether and water; (b) adding risedronic acid and sodium base such as NaOH, Na2CO3, and NaHCO3 to the mixture solvent to provide a risedronate sodium solution where the percentage of the hydrophilic organic solvent regarding water is 0.01-34%; (c) reacting the solution at a temperature of 45-70 deg.C for 0.5-30 hours to perform nucleation of hemipentahydrate of a risedronate sodium salt and growth of crystals; and (d) filtering the crystal solution or after cooling the crystal solution at a temperature of 0-25 deg.C, filtering it to obtain the crystals. Further, the percentage of the hydrophilic organic solvent regarding water is 14-17%.