This invention pertains generally to the field of chemical synthesis and purification, and more specifically to methods of synthesizing and purifying certain 3,7-diamino-phenothiazin-5-ium compounds (referred to herein as “diaminophenothiazinium compounds”) including Methylthioninium Chloride (MTC) (also known as Methylene Blue). In one embodiment, the e//i method comprises the steps of in order: a thiosulfonic acid formation (TSAF) as illustrated below, wherein the reaction is carried out in the presence of a thio sulfate and an oxidizing agent that is or comprises persulfate an oxidative coupling (OC); and a ring closure (RC). The resulting compounds and compositions comprising them (e.g., tablets, capsules) are useful in methods of medical treatment and diagnosis, etc., for example, tauopathies, or Alzheimer's disease (AD).
本发明涉及
化学合成和纯化领域,更具体地涉及合成和纯化某些3,7-二
氨基
苯并噻吩-5-ium化合物(以下简称“二
氨基
苯并噻吩化合物”),包括
氯化甲基
硫菲尼(
MTC)(也称为
亚甲蓝)。在一种实施例中,e//i方法包括以下步骤:首先进行
硫代
磺酸形成(
TSAF),反应在
硫代
硫酸盐和氧化剂(或包含过
硫酸盐)的存在下进行;然后进行氧化偶联(OC);最后进行环闭合(RC)。所得化合物及其组合物(例如,片剂、胶囊)在医疗治疗和诊断等方面有用,例如用于治疗tau蛋白病或阿尔茨海默病(AD)。