Patent EA-005008-B1 (EA)
Title: Alpha crystalline form of perindopril tert-butylamine salt
Inventor: PFEIFFER BRUNO
IPC: A61K38/00
Filed: 2001-07-06
Abstract: 1. alpha Crystalline form of a compound of formula (I): characterised by the following powder X-ray diffraction diagram, measured using a diffractometer (copper anticathode) and expressed in terms of inter-planar distances d, Bragg's angle 2 theta, intensity and relative intensity (expressed as a percentage with respect to the most intense ray): Angle 2 theta ([deg.])	Inter-planar distance d ( angstrom )	Intensity	Relative intensity 7.680	11.50	390	8.8 8.144	10.85	230	5.2 9.037	9.78	4410	100 10.947	8.08	182	4.1 13.150	6.73	82	1.9 13.687	6.46	83	1.9 14.627	6.05	582	13.2 15.412	5.74	770	17.5 16.573	5.34	1115	25.3 17.357	5.10	340	7.7 18.109	4.89	193	4.4 19.922	4.45	306	6.9 20.609	4.31	375	8.5 21.412	4.15	226	5.1 21.832	4.07	217	4.9 22.158	4.01	483	11 22.588	3.93	386	8.8 23.323	3.81	107	2.4 24.200	3.67	448	10.2 24.727	3.60	137	3.1 25.957	3.43	125	2.8 26.932	3.31	75	1.7 27.836	3.20	197	4.5 28.966	3.08	129	2.9 29.213	3.05	117	2.7 2. Process for the preparation of the [alpha] crystalline form of the compound of formula (I) according to claim 1, characterised in that a solution of perindopril tert-butylamine salt in ethyl acetate is heated at reflux and is then cooled gradually until crystallisation is complete. 3. Process according to claim 2, characterised in that the compound of formula (I) obtained by the preparation process described in patent specification EP 0 308 341 is used. 4. Process according to either claim 2 or claim 3, characterised in that the concentration of the compound of formula (I) in the ethyl acetate is from 70 to 90 g/litre. 5. Process according to any one of claims 2 to 4, characterised in that the solution of the compound of formula (I) in ethyl acetate at reflux is first cooled to a temperature of from 55 to 65 degree C. at a rate of from 5 to 10 degree C./hour, and then to ambient temperature. 6. Process according to any one of claims 2 to 4, characterised in that the solution of the compound of formula I in ethyl acetate is seeded during the cooling step at a temperature of from 76 to 65 degree C. 7. Process according to claim 5, characterised in that the solution of the compound of formula (I) in ethyl acetate at reflux is first cooled to a temperature of from 55 to 65 degree C. at a rate of from 6 to 8 degree C./hour, and then to ambient temperature. 8. Process according to any one of claims 2 to 7, characterised in that the perindopril tert-butylamine salt that is thereby obtained is in the form of readily filterable individual needles. 9. Pharmaceutical composition comprising as active ingredient the compound according to claim 1, in combination with one or more pharmaceutically acceptable, inert, non-toxic carriers. 10. Pharmaceutical composition according to claim 9 for use in the manufacture of medicaments for use as inhibitors of angiotensin I converting enzyme. 11. Pharmaceutical composition according to claim 10 for use in the manufacture of medicaments for use in the treatment of cardiovascular diseases. 12. Pharmaceutical composition according to any one of claims 9 to 11, characterised in that it also comprises a diuretic. 13. Pharmaceutical composition according to claim 12, characterised in that the diuretic is indapamide.