Preparation of citalopram comprises the steps of: (a) converting the compound of Formula (I) to a compound of Formula (II), wherein R in Formula (I) represents a C
2
to C
5
alkylene group which may be substituted or unsubstituted, and R
1
in the compounds of Formula (II) represents a carboxylic acid group or a salt or an ester thereof; and (b) converting the compound of Formula (II) to form citalopram or a pharmaceutically acceptable salt thereof, or a direct conversion of the compound of Formula (I) to citalopram
1
A method for the preparation of citalopram comprising reductive hydrolysis of a compound of Formula (IV)
1
wherein R is a N,N-disubstituted amid group or an optionally substituted 4,5-dihydro-1,3-oxazol-2-yl group, and conversion of the resulting 5-formyl compound to citalopram.
[EN] METHOD FOR THE PREPARATION OF CITALOPRAM<br/>[FR] METHODE DE PREPARATION DU CITALOPRAM
申请人:LUNDBECK & CO AS H
公开号:WO2000023431A1
公开(公告)日:2000-04-27
The present invention relates to a method for the preparation of citalopram or any of its enantiomers and acid addition salts thereof comprising treatment of a compound of formula (IV), wherein X is O or S; R1 - R2 are each independently selected from hydrogen and C¿1-6? alkyl, or R?1 and R2¿ together form a C¿2-5? alkylene chain thereby forming a spiro-ring; R?3¿ is selected from hydrogen and C¿1-6? alkyl, R?4¿ is selected from hydrogen, C¿1-6? alkyl, a carboxy group or a precursor group therefore, or R?3 and R4¿ together form a C¿2-5? alkylene chain thereby forming a spiro-ring, with a dehydration agent or alternatively where X is S, thermally cleavage of the thiazoline ring, or treatment in presence of a radical initiator, to form citalopram. The invention also relates to intermediates used in the new process for the preparation of citalopram, as well as citalopram prepared according to the new process.
The present invention relates to compounds of the general formula (I)
1
The compounds are useful in the treatment and/or prevention of conditions mediated by nuclear receptors, in particular the Peroxisome Proliferator-Activated Receptors (PPAR).
A method for the preparation of 5-cyanophthalide comprising treatment of a compound of formula IV
wherein X is O or S;
R
1
-R
2
are each independently selected from hydrogen and C
1-6
alkyl, or R
1
and R
2
together form a C
2-5
alkylene chain thereby forming a spiro-ring; R
3
is selected from hydrogen and C
1-6
alkyl, R
4
is selected from hydrogen, C
1-6
alkyl, a carboxy group or a precursor group therefore, or R
3
and R
4
together form a C
2-5
alkylene chain thereby forming a spiro-ring; with a dehydration agent or alternatively where X is S, thermally cleavage of the thiazoline ring or treatment with a radical initiator, such as peroxide or with light, to form 5-cyanophthalide, which is an important intermediate used in the preparation of the antidepressant drug citalopram.