In particular, rizatriptan or a pharmaceutically acceptable salt thereof, which includes a) Preparation of the diazonium salt of 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) Decarboxylaton 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.
具体而言,本发明涉及
利扎曲普坦或其药学上可接受的盐,包括a)制备
苯胺盐酸盐的重氮盐(II);随后还原和酸化以得到
肼(III);b)
肼盐酸盐(III)与α-酮-
δ-戊内酯原位反应,得到
肼酮(IV);c)
肼酮(IV)的费希尔
吲哚反应,得到
吡喃
吲哚酮(V),可选择性地随后进行
水解反应以得到(VI);d)(V)的酯交换或其
水解产物(VI)的酯化,得到(VII),其中R表示直链或支链C1-C4烷基链;e)将(VII)的羟基转化为
二甲氨基,得到
吲哚羧酸酯(VIII),其中R具有上述定义的含义;f)(VIII)的2-羧酰基团皂化为
吲哚羧酸(IX);和g)
吲哚羧酸(IX)的脱羧反应,得到
利扎曲普坦,最终获得其药学上可接受的盐。本发明还涉及合成
利扎曲普坦的中间体。