Crystalline base of citalopram
OwnerHans Petersen, Klaus Peter Bogeso +1inventors
InventorsHans Petersen, Klaus Peter Bogeso, Per Holm
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Abstract
The present invention relates to the crystalline base of the well known antidepressant drug citalopram, 1-[3-(dimethylamino)propyl]-1-(4-fluorophenyl)-1,3-dihydro-5-isobenzofurancarbonitrile, formulations of said base, a process for the preparation of purified salts of citalopram, such as the hydrobromide, using the base, the salts obtained by said process and formulations containing such salts.
Claims20
A process for the manufacture of a salt of citalopram, comprising the steps of:
- (a) freeing citalopram base;
- (b) precipitating the citalopram base in crystalline form;
- (c) optionally recrystallising the citalopram base one or more times;
- and
- (d) then transforming the citalopram base into a pharmaceutically acceptable citalopram salt.
A process for the manufacture of citalopram base or a salt of citalopram, wherein one or more impurities of the formula
- 5
- wherein Z is halogen, —O—SO2—(CF2)n—CF3, where n is 0-8, —CHO, —NHR1, —COOR2, —CONR2R3 wherein R2 and R3 are selected from hydrogen, alkyl, optionally substituted aryl or aralkyl, and R1 is hydrogen or alkylcarbonyl, is removed from a crude mixture of citalopram or from a crude salt of citalopram, comprising the steps of
- (a) precipitating citalopram base in crystalline form,
- (b) optionally re-crystallising the citalopram base one more times, and
- (c) transforming the citalopram base into a pharmaceutically acceptable salt of citalopram.
A crystalline base of citalopram, or a hydrochloride or hydrobromide salt of citalopram, having a purity of more than 99.8% w/w.
A crystalline base of citalopram, or a hydrochloride or hydrobromide salt of citalopram, having a purity of more than 99.9% w/w.
Dependencies are inferred from the claim text.