Claims for Patent: 5,985,864

Summary for Patent: 5,985,864

Title:	Polymorphs of donepezil hydrochloride and process for production
Abstract:	Donepezil hydrochloride, 1-benzyl-4-[(5,6-dimethoxy-1-indanon)-2-yl]methylpiperidine hydrochloride, is provided here in the form of four polymorphs which are stable against heat and humidity in the pharmaceutical use. They can be industrially produced. They are specified by peaks in X-ray powder diffraction pattern and absorption peaks in infrared absorption spectra in potassium bromide.
Inventor(s):	Imai; Akio (Ibaraki, JP), Watanabe; Hideaki (Ibaraki, JP), Kajima; Takashi (Ibaraki, JP), Ishihama; Yasushi (Ibaraki, JP), Ohtsuka; Akiyo (Ibaraki, JP), Tanaka; Tomohide (Ibaraki, JP), Narabu; Yukio (Ibaraki, JP)
Assignee:	Eisai Co., Ltd. (Tokyo, JP)
Application Number:	08/870,394
Patent Claims:	1. Donepezil hydrochloride, 1-benzyl-4-[(5,6-dimethoxy-1-indanon)-2-yl]methylpiperdine hydrochloride, in the form of polymorphs selected from the group consisting of (II), (IV) and (V), each polymorph being specified by peaks at below shown diffraction degrees with the below shown intensity in terms of I/I.sub.o in x-ray powder diffraction pattern and the below shown absorption peaks in infrared absorption spectra in potassium bromide in terms of reciprocal centimeters: Wave numbers (cm.sup.-1) if infrared absorption spectra in potassium bromide are: 560.1, 698.9, 749.1, 846.2, 947.6, 1036.1, 1119.3, 1222.7, 1266.4, 1318.7, 1364.1, 1458.3, 1500.9, 1522.3, 1534.0, 1542.6, 1560.2, 1570.3, 1592.0, 1637.0, 1647.9, 1654.4, 1689.5, 1718.3, 1734.7, 1751.7, 1773.9, 1793.8, 1830.7, 1846.0, 1870.1, 2354.1, 2489.9, 2927.9, 3448.1 cm.sup.-1 Wave numbers (cm.sup.-1) of infrared absorption spectra in potassium bromide are: 561.5, 709.0, 766.2, 786.3, 804.9, 857.0, 944.3, 979.3, 1041.5, 1118.7, 1264.6, 1318.7, 1364.1, 1458.1, 1499.2, 1542.5, 1560.1, 1588.1, 1636.6, 1647.8, 1654.3, 1684.3, 1718.2, 1734.4, 1751.4, 1773.7, 1793.5, 1830.5, 1845.8, 1870.1, 2344.8, 2369.3, 2719.2, 2922.9, 3324.0 cm.sup.-1 Wave numbers (cm.sup.-1) of infrared absorption spectra in potassium bromide are: 506.5, 559.7, 594.4, 698.0, 740.8, 805.1, 861.9, 948.5, 972.1, 1039.9, 1120.8, 1220.7, 1264.8, 1314.6, 1364.1, 1458.0, 1499.5, 1542.5, 1560.2, 1592.1, 1692.9, 2500.1, 2924.2, 2998.9, 3422.1, cm.sup.-1. 2. A process for producing the polymorph (II) of Donepezil hydrochloride as defined in claim 1, which comprises the steps of dissolving Donepezil hydrochloride in ethanol and adding diethyl ether or isopropyl ether to the solution. 3. A process for producing the polymorph (II) of Donepezil hydrochloride as defined in claim 1, which comprises the steps of dissolving Donepezil hydrochloride in ethanol, adding isopropyl ether to the solution, stirring the mixture for 10 to 30 minutes after having precipitated and filtrating the crystalline precipitates. 4. A process for producing the polymorph (II) of Donepezil hydrochloride as defined in claim 1, which comprises the steps of dissolving Donepezil and hydrochloric acid or hydrogen chloride in ethanol and adding diethyl ether to the solution. 5. A process for producing the polymorph (II) of Donepezil hydrochloride as defined in claim 1, which comprises the steps of dissolving Donepezil in ethanol, adding hydrochloric acid or hydrogen chloride to the solution and concentrating the mixture. 6. A process for producing the polymorph (II) of Donepezil hydrochloride as defined in claim 1, which comprises the steps of dissolving Donepezil in ethanol, adding hydrochloric acid or hydrogen chloride to the solution and adding isopropyl ether to the mixture. 7. The process as claimed in claim 6, which further comprises filtrating crystalline precipitates after having stirred for 10 to 60 minutes. 8. A process for producing the polymorph (IV) of Donepezil hydrochloride as defined in claim 1, which comprises the step of humidifying the polymorph (II) as defined in claim 1. 9. A process for producing the polymorph (II) of Donepezil hydrochloride as defined in claim 1, which comprises the steps of dissolving Donepezil in ethanol, adding hydrochloric acid or hydrogen chloride to the solution and adding tert-butyl methyl ether successively. 10. A process for producing the polymorph (II) of Donepezil hydrochloride as defined in claim 1, which comprises the steps of dissolving Donepezil in isopropyl alcohol or in methylene chloride and adding hydrochloric acid or hydrogen chloride to the solution. 11. A process for producing the polymorph (II) of Donepezil hydrochloride as defined in claim 1, which comprises the steps of dissolving Donepezil in acetone, adding hydrochloric acid or hydrogen chloride to the solution and filtrating the crystalline precipitates within 30 minuets from the separation of crystals. 12. A process for producing the polymorph (II) of Donepezil hydrochloride as defined in claim 1, which comprises the steps of dissolving Donepezil hydrochloride in ethanol and adding tert-butyl methyl ether to the solution at temperature in the range of 10 to 30.degree. C. 13. A process for producing the polymorph (II) of Donepezil hydrochloride as defined in claim 1, which comprises the steps of dissolving Donepezil hydrochloride in ethanol and adding this solution to diisopropyl ether. 14. A process for producing the polymorph (II) of Donepezil hydrochloride as defined in claim 1, which comprises the steps of dissolving Donepezil hydrochloride in methylene chloride and adding tert-butyl methyl ether to the solution. 15. A process for producing the polymorph (II) of Donepezil hydrochloride as defined in claim 1, which comprises the step of drying the polymorph (I) or amorphous form of Donepezil hydrochloride. 16. A process for producing the polymorph (IV) of Donepezil hydrochloride as defined in claim 1, which comprises the step of humidifying the polymorph (II) as defined in claim 1. 17. A process for producing the polymorph (IV) of Donepezil hydrochloride as defined in claim 1, which comprises the steps of dissolving Donepezil in water with or without tetrahydrofuran and adding hydrochloric acid or hydrogen chloride to the solution. 18. A process for producing the polymorph (IV) of Donepezil hydrochloride as defined in claim 1, which comprises the steps of dissolving Donepezil in hydrochloric acid and adding tetrahydrofuran to the solution. 19. A process for producing the polymorph (IV) of Donepezil hydrochloride as defined in claim 1, which comprises the steps of dissolving Donepezil in toluene and adding hydrochloric acid to the solution. 20. A process for producing the polymorph (IV) of Donepezil hydrochloride as defined in claim 1, which comprises the steps of dissolving Donepezil in n-hexane and adding hydrochloric acid to the solution. 21. A process for producing the polymorph (IV) of Donepezil hydrochloride as defined in claim 1, which comprises the step of crystallizing Donepezil in a mixture of methanol and hydrochloric acid. 22. A process for producing the polymorph (IV) of Donepezil hydrochloride as defined in claim 1, which comprises the step of crystallizing Donepezil hydrochloride from water. 23. A process for producing the polymorph (IV) of Donepezil hydrochloride as defined in claim 1, which comprises the step of humidifying the amorphous form of Donepezil hydrochloride. 24. A process for producing the polymorph (IV) of Donepezil hydrochloride as defined in claim 1, which comprises the step of humidifying the polymorph (II) of Donepezil hydrochloride. 25. A process for producing the polymorph (V) of Donepezil hydrochloride as defined in claim 1, which comprises the step of drying the polymorph (IV) of Donepezil hydrochloride. 26. A method for treating a disease accompanied by acetylcholinesterase activity which comprises administering to a human patient in need thereof a pharmacologically effective amount of the Donepezil hydrochloride in the form of a polymorph as defined in claim 1 for inhibiting the acetylcholinesterase activity. 27. The method as claimed in claim 1, in which the disease is senile dementia. 28. The method as claimed in claim 1, in which the disease is senile dementia of the Alzheimer type. 29. A therapeutical composition which comprises a pharmacologically effective amount of Donepezil hydrochloride in the form of polymorph as defined in claim 1 and a pharmacologically acceptable carrier. 30. The Donepezil hydrochloride as claimed in claim 1, which is in the form of polymorph (II). 31. The Donepezil hydrochloride as claimed in claim 1, which is in the form of polymorph (III). 32. The Donepezil hydrochloride as claimed in claim 1, which is in the form of polymorph (IV). 33. The Donepezil hydrochloride as claimed in claim 1, which is in the form of polymorph (V).