20100137581 | PROCESS FOR PREPARATION OF SUBSTANTIALLY PURE POLYMORPHIC FORM I OF OLANZAPINE - A process for preparation of substantially pure polymorphic Form I of olazapine consists in that olanzapine starting material is subjected to: a) at least one digestion step in an acidic aqueous medium, with an optional addition of active charcoal, and then to neutralizing to pH within the range from about 6.0 to about 11.0, and b) at least one step of separation of impurities in a water—organic solvent system, followed by crystallization from the solution in methylene chloride, and wherein steps a) and b) are separated by steps of isolation of precipitate of olanzapine and can be accomplished in any order. | 06-03-2010 |