1092370-41-6Relevant articles and documents
NOVEL PROCESS
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Page/Page column 12-13, (2009/01/24)
The present invention relates to a novel process for the preparation of rizatriptan and its pharmaceutically acceptable salts. It provides a novel process for the preparation of highly pure rizatriptan, which can be easily adopted for commercial production with a high degree of consistency in purity and yield. Subsequently the rizatriptan base preparedcan be converted into any suitable pharmaceutically acceptable salt, such as the oxalate, succinate or benzoate salt,for dosage form preparation. The present invention also provides a composition comprising rizatriptan useful for the manufacture of a medicament for the treatment or prevention of migraine.
PROCESS FOR PREPARING RIZATRIPTAN
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Page 12-13; 15, (2008/06/13)
In particular, rizatriptan or a pharmaceutically acceptable salt thereof, which includes a) Preparation of the diazonium salt of the aniline hydrochloride (II); followed by reduction and acidification to give the hydrazine (III); b) reaction in situ of the hydrazine hydrochloride (III) with α-keto-δ-valerolactone, to give the hydrazone (IV); c) Fischer indole reaction of the hydrazone (IV), to give the pyranoindolone (V), optionally followed by a hydrolysis reaction to give (VI); d) Transesterification of (V) or esterification of its hydrolysis product (VI), to give (VII), where R means straight or branched C1-C4 alkyl chain; e) Conversion of the hydroxyl group of (VII) into dimethylamino, to give the indolecarboxylate (VIII), where R has the meaning defined above; f) Saponification of the 2-carboalkoxy group of (VIII) to give indolecarboxylic acid (IX); and g) Decarboxylation of the indolecarboxylic acid (IX) to give rizatriptan and, eventually, to obtain a pharmaceutically acceptable salt thereof. The invention also relates to synthesis intermediates to obtain rizatriptan.