Barium salt of benzimidazole derivative
The invention relates to crystalline barium salt of (S)-omeprazole, which is (S)-5-methoxy-2-[[(4-methoxy-3,5-dimethyl-2-pyridinyl)-methyl]sulfinyl]-1H-benzimidazole. The invention also relates to processes for preparing crystalline barium salt of (S)-omeprazole and pharmaceutical compositions that include the crystalline barium salt of (S)-omeprazole so prepared.
1. A process for the preparation of (S)-omeprazole barium comprising the step of contacting (S)-omeprazole freebase, or its salt, with a barium containing compound that is capable of forming the barium salt (S)-omeprazole in a solvent, provided that a base is used when (s)-omeprazole base is used as the starting material, wherein the solvent comprises water, ketones, alcohols, esters, cyclic ethers, chlorinated hydrocarbons, nitriles, dipolar aprotic solvents, and mixtures thereof.
2. The process according to claim 1 , wherein the barium containing compound is the barium salt of an inorganic acid.
3. The process according to claim 2 , wherein the barium salt is selected from the group consisting of barium chloride, barium nitrate, barium phosphate, barium carbonate, and barium sulfate.
4. The process according to claim 1 , wherein the barium salt of an organic acid is used.
5. The process according to claim 4 , wherein the barium salt is selected from the group consisting of barium oxalate, barium acetate, barium lactate, barium succinate, barium citrate, and barium tartrate.
6. The process according to claim 1 , wherein the base is selected from the group consisting of alkali metal hydroxides, alkali metal carbonates, alkali metal bicarbonates and ammonium hydroxide.
7. The process according to claim 6 , wherein the base is selected from the group consisting of sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, and sodium bicarbonate.
8. The process according to claim 1 , wherein the solvent is selected from the group consisting of water, acetone, methanol and mixtures thereof.
9. The process according to claim 1 , wherein the product obtained is crystalline (S)-omeprazole barium.
10. The process according to claim 1 , which further comprises removing the solvent by vacuum distillation or spray drying.