Claims for Patent: 7,285,668

Summary for Patent: 7,285,668

Title:	Process for the crystallization of (R)- or (S)-lansoprazole
Abstract:	The present invention relates to a production method of a crystal of (R)-lansoprazole or (S)-lansoprazole, which includes crystallization at a temperature of about 0.degree. C. to about 35.degree. C. from a C.sub.1-4 alkyl acetate solution containing (R)-lansoprazole or (S)-lansoprazole at a concentration of about 0.1 g/mL to about 0.5 g/mL and the like. According to the production method of the present invention, a crystal of (R)-lansoprazole or (S)-lansoprazole superior in preservation stability can be produced efficiently on an industrial large scale.
Inventor(s):	Hashimoto; Hideo (Kobe, JP), Urai; Tadashi (Kawanishi, JP)
Assignee:	Takeda Pharmaceutical Company Limited (Osaka, JP)
Application Number:	10/432,798
Patent Litigation and PTAB cases:	See patent lawsuits and PTAB cases for patent 7,285,668
Patent Claims:	1. A method for producing a crystal of (R)-2-[[[3-methyl-4-(2,2,2-trifluoroethoxy)-2-pyridinyl]methyl]sulfinyl]-- 1H-benzimidazole or (S)-2-[[[3-methyl-4-(2,2,2-trifluoroethoxy)-2-pyridinyl]methyl]sulfinyl]-- 1H-benzimidazole, which comprises crystallizing at a temperature of about 0.degree. C. to about 35.degree. C. from a C.sub.1-4 alkyl acetate solution containing (R)-2-[[[3-methyl-4-(2,2,2-trifluoroethoxy)-2-pyridinyl]methyl]sulfinyl]-- 1H-benzimidazole or (S)-2-[[[3-methyl-4-(2,2,2-trifluoroethoxy)-2-pyridinyl]methyl]sulfinyl]-- 1H-benzimidazole at a concentration of about 0.1 g/mL to about 0.5 g/mL. 2. A method for producing a crystal of (R)-2-[[[3-methyl-4-(2,2,2-trifluoroethoxy)-2-pyridinyl]methyl]sulfinyl]-- 1H-benzimidazole or (S)-2-[[[3-methyl-4-(2,2,2-trifluoroethoxy)-2-pyridinyl]methyl]sulfinyl]-- 1H-benzimidazole, which comprises crystallizing at a temperature of about 0.degree. C. to about 35.degree. C. from a C.sub.1-4 alkyl acetate solution containing (R)-2-[[[3-methyl-4-(2,2,2-trifluoroethoxy)-2-pyridinyl]methyl]sulfinyl]-- 1H-benzimidazole or (S)-2-[[[3-methyl-4-(2,2,2-trifluoroethoxy)-2-pyridinyl]methyl]sulfinyl]-- 1H-benzimidazole at a concentration of about 0.1 g/mL to about 0.5 g/mL, and adding dropwise to the C.sub.1-4 alkyl acetate solution, at the same temperature, C.sub.5-8 hydrocarbon in an amount of not more than 7 times the amount of the C.sub.1-4 alkyl acetate solution. 3. The method of claim 1, wherein the crystallization temperature is about 20.degree. C. to about 30.degree. C. 4. The method of claim 1, wherein the crystallization is conducted for about 30 minutes to about 4 hours. 5. The method of claim 1, wherein the C.sub.1-4 alkyl acetate is ethyl acetate or propyl acetate. 6. The method of claim 2, wherein the C.sub.5-8 hydrocarbon is added in an amount of not more than 5 times the amount of the C.sub.1-4 alkyl acetate solution. 7. The method of claim 2, wherein the C.sub.5-8 hydrocarbon is heptane or hexane. 8. The method of claim 2, wherein the C.sub.5-8 hydrocarbon is added dropwise over about 15 minutes to about 4 hours. 9. A crystal of (R)-2-[[[3-methyl-4-(2,2,2-trifluoroethoxy)-2-pyridinyl]methyl]sulfinyl]-- 1H-benzimidazole or (S)-2-[[[3-methyl-4-(2,2,2-trifluoroethoxy)-2-pyridinyl]methyl]sulfinyl]-- 1H-benzimidazole having a melting start temperature of not lower than about 131.degree. C. 10. The crystal of claim 9, wherein the melting start temperature is about 135.degree. C. 11. The method of claim 2, wherein the crystallization temperature is about 20.degree. C. to about 30.degree. C. 12. The method of claim 2, wherein the crystallization is conducted for about 30 minutes to about 4 hours. 13. The method of claim 2, wherein the C.sub.1-4 alkyl acetate is ethyl acetate or acetate.