A PROCESS FOR THE SYNTHESIS OF 1-HYDROXY-3-(N-METHYLPENTYLAMINO) PROPYLIDENE BISPHOSPHONIC ACID MONOSODIUM SALT, MONOHYDRATE

摘要

A process for the synthesis of 1-hydroxy-3-(N-methylpentylamino) propylidene bisphosphonic acid monosodium salt, monohydrate which consists in the reaction of phosphorus trichloride with an aqueous solution of 3-(N-methylpentylamino)propionic acid hydrochloride at a temperature of 0-80°C, removing excess unreacted phosphorus trichloride, hydrolysis of the reaction mixture under reflux, conversion of 1-hydroxy-3-(N- methylpentylamino) propylidene bisphosphonic acid into its monosodium salt using sodium cation-containing alkaline substances, crystallisation using an anti-solvent. Also disclosed is a process for the synthesis of a polymorphic form of 1-hydroxy-3-(N-methylpentylamino) propylidene bisphosphonic acid monosodium salt, monohydrate which consists of initiating and carryout the crystallisation using acetone at a temperature of 0-5°C.