Process for preparing valsartan

• US 7,923,567 B2
• Filed: 06/15/2010
• Issued: 04/12/2011
• Est. Priority Date: 08/22/2005
• Status: Expired due to Fees

• Current Assignee: Alembic Limited (Nirayu Pvt Ltd.)
• Original Assignee: Alembic Limited (Nirayu Pvt Ltd.)
• Inventors: Soni, Rohit Ravikant, Ghotikar, Ravindra Charudatta, Shah, Hetal Remeshchandra, Pandey, Anand Kumar, Vasoya, Sanjay Lakhabhai
• Primary Examiner(s): Saeed; Kamal A
• Application Number:
  US12/815,950
• Publication Number:
  US 20100249430A1
• Time in Patent Office: 301 Days
• Field of Search: None
• US Class Current: 548/253
• CPC Class Codes: C07C 255/58 containing cyano groups and singly-bound nitrogen atoms, not being further bound to other hetero atoms, bound to the carbon skeleton
• CPC Class Codes: C07D 257/04 Five-membered rings

Abstract

The invention relates to novel compound of formula (IV), which is an organic acid salt of N-[(2′-cyanobiphenyl-4-yl)methyl]-(L)-valine ester. This compound is an useful intermediate for process of preparation of Valsartan of formula (I), chemically known as (S)-N-(1-Carboxy-2-methylprop-1-yl)-N-pentanoyl-N-[2′-(1H-terazol-5-yl)biphenyl-4-ylmethyl]amine. This invention also relates to a process for preparing Valsartan using novel intermediate of formula (IV).

Claims

1. A process for the preparation of (S)-N-(1-carboxy-2-methylprop-1-yl)-N-pentanoyl-N-[2′

-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]amine (Valsartan) of formula I comprising;

2. A process according to claim 1, wherein said base in step (a) is selected from organic base, inorganic base or mixtures thereof.

3. A process according to claim 2, wherein said base is selected from sodium hydroxide, potassium hydroxide, calcium hydroxide, magnesium hydroxide, sodium bicarbonate, potassium bicarbonate, sodium carbonate, potassium carbonate, cesium carbonate, sodium methoxide, potassium methoxide, sodium ethoxide, potassium ethoxide, potassium tert-butoxide, ammonia, triethyl amine, pyridine and the like.

4. A process according to claim 3, wherein base in step (a) is sodium carbonate or potassium carbonate.

5. A process according to claim 1, wherein said catalyst in step (a) is alkali metal halide selected from sodium iodide or potassium iodide.

6. A process according to claim 1, wherein said solvent in step (a) is selected from dimethylformamide, dimethylsulfoxide, acetonitrile, xylene, toluene, halogenated hydrocarbon such as methylenedichloride, ethylenedichloride or chloroform, alcohol such as methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, tert-butanol, n-amyl alcohol, isoamyl alcohol or tert-amyl alcohol.

7. A process according to claim 6, wherein solvent is acetonitrile.

8. A process according to claim 1, wherein said organic acid in step (b) is selected from oxalic acid, acetic acid, formic acid, malic acid, maleic acid, malonic acid, succinic acid, fumaric acid, phthalic acid, terephthalic acid, citric acid, tartaric acid, methane sulfonic acid, ethanesulfonic acid, p-toluenesulfonic acid, trifluoroacetic acid, ascorbic acid and the like.

9. A process according to claim 8, wherein organic acid is oxalic acid.

10. A process according to claim 1, wherein step (b) is carried out in presence of solvent selected from water, methanol, ethanol, propanol, isopropanol, tert-butanol, toluene, n-hexane, o-xylene, n-heptane, methylenedichloride, ethylenedichloride, acetonitrile, dimethylformamide, dimethylsulfoxide, acetonitrile or mixture thereof.

11. A process according to claim 10, wherein said solvent is o-xylene, water or mixture thereof.

12. A process according to claim 1, wherein said base in step (c) is selected from sodium hydroxide, potassium hydroxide, calcium hydroxide, magnesium hydroxide, sodium bicarbonate, potassium bicarbonate, sodium carbonate, potassium carbonate, cesium carbonate, sodium methoxide, potassium methoxide, sodium ethoxide, potassium ethoxide, potassium tert-butoxide, ammonia, triethyl amine, pyridine and the like.

13. A process according to claim 12, wherein said base is sodium bicarbonate or potassium bicarbonate.

14. A process according to claim 1, wherein said organic solvent in step (c) selected from group comprising methylenedichloride, chloroform, ethylenedichloride, o-xylene, toluene, dimethylformamide, dimethylacetamide, dimethylsulfoxide.

15. A process according to claim 14, wherein said organic solvent is o-xylene.