合成制备方法如下:
从5-氯或5-甲氧基取代的3-氨基-8-甲氧基[1,2,4]三唑[4,3-c]嘧啶出发,在醇溶剂中与甲醇盐反应生成2-氨基-5,8-二甲氧基[1,2,4]三唑[1,5-c]嘧啶。当3-取代基为氯时,可直接进行重排和甲氧基化反应。
以2-甲氧基乙酸甲酯为起始原料,与甲酸甲酯、甲醇钠反应生成3-羟基-2-甲氧基丙烯酸甲酯的钠盐。再与甲基异硫脲反应得到2,5-二甲氧基-4-羟基嘧啶,接着用三氯氧磷进行氯化处理,得4-氯-2,5-二甲氧基嘧啶。随后与水合脐反应生成2,5-二甲氧基-4-肼基嘧啶。再使用溴化氰环合得到3-氨基-5,8-二甲氧基[1,2,4]三唑并[[4,3-c]嘧啶,最后与甲醇钠反应得到2-氨基-5,8-二甲氧基[1,2,4]三唑并[1,5,c]嘧啶。
中文名称 | 英文名称 | CAS号 | 化学式 | 分子量 |
---|---|---|---|---|
—— | 5-chloro-8-methoxy[1,2,4]triazolo[1,5-c]pyrimidin-2-amine | 1350919-12-8 | C6H6ClN5O | 199.6 |
—— | 3-amino-5,8-dimethoxy[1,2,4]triazolo[4,3-c]pyrimidine | —— | C7H9N5O2 | 195.181 |
中文名称 | 英文名称 | CAS号 | 化学式 | 分子量 |
---|---|---|---|---|
—— | 3,5-dichloro-N-(5,8-dimethoxy-1,2,4-triazolo[1,5-c]pyrimidin-2-yl)benzenesulfonamide | 1138323-47-3 | C13H11Cl2N5O4S | 404.233 |
—— | 2,6-dichloro-N-(5,8-dimethoxy-1,2,4-triazolo[1,5-c]pyrimidin-2-yl)benzenesulfonamide | 219713-14-1 | C13H11Cl2N5O4S | 404.233 |
—— | 2,5-dichloro-N-(5,8-dimethoxy-1,2,4-triazolo[1,5-c]pyrimidin-2-yl)benzenesulfonamide | 219714-11-1 | C13H11Cl2N5O4S | 404.233 |
—— | 2-methoxy-N-(5,8-dimethoxy-1,2,4-triazolo[1,5-c]pyrimidin-2-yl)benzenesulfonamide | 219713-00-5 | C14H15N5O5S | 365.37 |
—— | 2,6-dimethoxy-N-(5,8-dimethoxy-1,2,4-triazolo[1,5-c]pyrimidin-2-yl)benzenesulfonamide | 219713-28-7 | C15H17N5O6S | 395.396 |
—— | 2-trifluoromethyl-N-(5,8-dimethoxy-1,2,4-triazolo[1,5-c]pyrimidin-2-yl)benzenesulfonamide | 219712-99-9 | C14H12F3N5O4S | 403.342 |
—— | N-(5,8-dimethoxy-(1,2,4)triazolo-(1,5-c)pyrimidin-2-yl)-2-bromo-6-trifluoromethylbenzenesulfonamide | 1431291-87-0 | C14H11BrF3N5O4S | 482.238 |
—— | N-(5,8-dimethoxy-(1,2,4)triazolo-(1,5-c)pyrimidin-2-yl)-2-fluoro-6-trifluoromethylbenzenesulfonamide | —— | C14H11F4N5O4S | 421.332 |
—— | 2-methoxy-6-trifluoromethyl-N-(5,8-dimethoxy-1,2,4-triazolo[1,5-c]pyrimidin-2-yl)benzenesulfonamide | 219713-19-6 | C15H14F3N5O5S | 433.368 |
—— | 2-ethoxy-6-trifluoromethyl-N-(5,8-dimethoxy-1,2,4-triazolo[1,5-c]pyrimidin-2-yl)benzenesulfonamide | 219713-46-9 | C16H16F3N5O5S | 447.395 |
—— | 2-(2-fluoroethoxy)-6-trifluoromethyl-N-(5,8-dimethoxy-1,2,4-triazolo[1,5-c]pyrimidin-2-yl)benzenesulfonamide | 219714-72-4 | C16H15F4N5O5S | 465.385 |
—— | 2-(3-fluoropropoxy)-6-trifluoromethyl-N-(5,8-dimethoxy-1,2,4-triazolo[1,5-c]pyrimidin-2-yl)benzenesulfonamide | 1176126-22-9 | C17H17F4N5O5S | 479.412 |
五氟磺草胺 | 2-(2,2-difluoroethoxy)-N-(5,8-dimethoxy-[1,2,4]triazolo[1,5-c]pyrimidin-2-yl)-6-(trifluoromethyl)benzenesulfonamide | 219714-96-2 | C16H14F5N5O5S | 483.4 |
—— | 2-(2,2,2-trifluoroethoxy)-6-trifluoromethyl-N-(5,8-dimethoxy-1,2,4-triazolo[1,5-c]pyrimidin-2-yl)benzenesulfonamide | 219714-91-7 | C16H13F6N5O5S | 501.366 |
—— | 2-[2-fluoro-1-(fluoromethyl)ethoxy]-6-trifluoromethyl-N-(5,8-dimethoxy-1,2,4-triazolo[1,5-c]pyrimidin-2-yl)benzenesulfonamide | 219714-93-9 | C17H16F5N5O5S | 497.403 |
—— | N-(5,8-dimethoxy[1,2,4]triazolo[1,5-c]pyrimidin-2-yl)-2-methoxy-4-(trifluoromethyl)pyridine-3-sulfonamide | 219714-45-1 | C14H13F3N6O5S | 434.356 |
An efficient nine-step synthesis of 2-(2,2-difluoroethoxy)-6-trifluoromethyl- N-(5,8-dimethoxy-1,2,4-triazolo[1,5-c] -pyrimidine-2-yl) benzenesulfonamide has been developed. The starting material 4-nitro-2-(trifluoromethyl)aniline starting material was converted via 2-bromo-4-amino-6-trifluoromethylaniline and 2-bromo-4-acetamido-6-trifluoro-methylbenzenesulfonic acid to 2-bromo-6-trilfuoromethylbenzenesulfonic acid. This was then combined with 2-amino-5,8-dimethoxy-1,2,4-triazolo[1.5-c]pyrimidine to give the target molecule. Compared with the reported method, this approach has advantages in its shorter reaction time, milder reaction conditions and easier purifiction. Moreover, the overall yield has been improved to 22.9% which is twice of that of the reported method.