In particular, this invention relates to the synthesis intermediates (IV), (V), (VI) and (VIII) useful for preparing zolmitriptanzohnitriptan 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 hydrazine (III); b) In situ Reaction of the hydrazine hydrochloride (III) with α-keto-δ-valerolactone, to give the hydrazone (IV); c) Fischer indole synthesis of the hydrazone (IV), to give the pyranoindolone of formula (V); d) Transesterification of the pyranoindolone (V) to provide the compound (VI), in which R means a straight or branched C1-C4 alkyl; e) Conversion of the hydroxyl group of the compound (VI) into dimethylamino to give the indolecarboxylate (VII), in which R means a straight or branched C1-C4 alkyl; f) Saponification of the 2-carboalkoxy group of the compound (VII), to provide indolecarboxylic acid (VIII); g) Decarboxylation of the indolecarboxylic acid (VIII), to provide zolmitriptan and, eventually, to provide a pharmaceutically acceptable salt thereof.
特别是,本发明涉及用于制备左米曲普坦唑替普坦或其药学上可接受的盐的合成中间体(IV),(V),(VI)和(VIII),其包括a)制备
苯胺盐酸盐(II)的重氮盐;随后还原并酸化以给出
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
吲哚合成,得到式(V)的
吡喃
吲哚酮;d)
吡喃
吲哚酮(V)的转酯化,以提供化合物(VI),其中R表示直链或支链C1-C4烷基;e)将化合物(VI)的羟基转化为
二甲氨基,以给出
吲哚羧酸酯(VII),其中R表示直链或支链C1-C4烷基;f)化合物(VII)的2-羧基烷氧基团皂化,以提供
吲哚羧酸(VIII);g)
吲哚羧酸(VIII)的脱羧作用,以提供左米曲普坦,最终提供其药学上可接受的盐。