It relates to a preparation process of 2'-(benzyloxy)-3'-nitro-1,1'-biphenyl-3- carboxylic acid or a salt thereof comprising reacting 2-(benzyloxy)-1-bromo- 3-nitrobenzene with a either 3-carboxyphenylboronic acid or a salt thereof or a (C1-C4)-alkyl ester thereof in the presence of Pd(OAc)2, tricydohexylphosphine, a base, an appropriate solvent, and at an appropriate temperature; if appropriate, submitting the compound thus obtained to a hydrolysis reaction; and isolating the compound thus obtained in form of a salt of compound of formula (VI) or in form of the free acid by adding an acid. It also comprises the further preparation to eltrombopag or its salts from the new intermediate thus obtained by subsequent reduction of the nitro group and deprotection of the phenol, conversion of the amine intermediate obtained in a diazonium derivative, and either (1) subsequent reaction with ethyl acetoacetate and with (3,4-dimethylphenyl)hydrazine or a salt thereof, occurring the pyrazole ring formation by intermolecular cyclization, or (2) introduction of the pyrazole ring by reaction with 1-(3,4-dimethylphenyl)-3-methyl-3-pyrazolin-5-one.
这段文字描述了2'-(苄氧基)-3'-硝基-1,1'-
联苯-3-
羧酸或其盐的制备过程,包括在Pd(OAc)2、
三环己基膦、一种碱、适当的溶剂和适当的温度下,将
2-(苄氧基)-1-溴-3-硝基苯与3-羧基苯
硼酸或其盐或其(C1-C4)烷基酯之一反应;如适当,将得到的化合物提交给
水解反应;通过加入酸,以化合物的盐的形式或自由酸的形式分离得到的化合物,其为化合物的公式(VI)的盐或自由酸形式。它还包括从所得的新中间体中进一步制备
厄洛替尼或其盐,方法为随后还原硝基团并去保护
酚基,将获得的胺中间体转化为重氮衍
生物,然后(1)与
乙酰乙酸乙酯和(3,4-二甲基苯基)
肼或其盐反应,通过分子间环化发生
吡唑环形成,或者(2)通过与1-(3,4-二甲基苯基)-
3-甲基-3-吡唑啉-5-酮反应引入
吡唑环。