The invention relates to a process for the synthesis of compounds of the formula I ##STR1## wherein R.sub.1 -R.sub.5 are as defined herein. The process is a multistep process which comprises acylating a 2-benzoxazolinone with an alkanoic anhydride to form an acylated carbamate, hydrolyzing the carbamate, reacting the resultant aminophenol with haloalkanoyl halide to form a substituted benzoxazine, reacting the benzoxazine with an aldehyde, alkylating the resultant aminomethyl compound with an alkylating agent to form a quaternary ammonium salt, reacting the salt with an alkali metal cyanide to form a nitrile, hydrolyzing the nitrile and reacting the resultant carboxylic acid with hydrazine. The compounds are useful as cardiotonic and vasodilating agents and as inhibitors of phosphodiesterase fraction III and platelet aggregation. In addition, the compounds are active as smooth muscle relaxants and bronchodilators.
本发明涉及一种合成式I的化合物的方法,其中R.sub.1-R.sub.5的定义如本文所述。该方法是一种多步骤的过程,包括用烷基酸酐酰化2-苯并
噁唑酮形成酰化的
氨基甲酸酯,
水解
氨基甲酸酯,将生成的
氨基
酚与卤代烷
酰卤反应形成取代苯并噁嗪,将苯并噁嗪与醛反应,用烷基化剂烷基化生成的
氨甲基化合物形成季
铵盐,将盐与碱
金属
氰化物反应形成腈,
水解腈并将生成的
羧酸与
肼反应。这些化合物可用作心脏强心和扩血管剂,以及
磷酸二酯酶III分数和血小板聚集的
抑制剂。此外,这些化合物还具有平滑肌松弛剂和支气管扩张剂的活性。