申请人:Veb Arzneimittelwerk Dresden
公开号:US04495351A1
公开(公告)日:1985-01-22
A method is disclosed for production of 1-alkyl-4(1H)-oxo-cinnolin-3-carboxylic acids. Mesoxalic acid dialkylester-3,4-methylenedioxy-phenylhydrazone is saponified using 1 to 1.5 Mol alkali into the corresponding monoalkylester, which is cyclicized with a Friedel-Crafts catalyst in the presence of a carboxylic acid anhydride into 6,7-methylenedioxy-4(1H)-oxo-cinnolin-3-carboxylic acid alkylester, which is alkylated with a C.sub.1 -C.sub.4 alkyl halogenide in the presence of alkali in a suitable solvent, after which the ester is saponified. Small amounts of byproduct alkylated in the 2-position are removed by brief heating and precipitation from alkaline solution, leaving a pure 1-alkyl product. The product is useful for the treatment of urinary tract infections.
本发明公开了一种制备1-烷基-4(1H)-氧代-香豆素-3-羧酸的方法。将甲基草酸双烷基酯-3,4-亚甲基二氧基-苯基肼用1至1.5摩尔碱皂化成相应的单烷基酯,然后在羧酸酐存在下,通过Friedel-Crafts催化剂环化成6,7-亚甲基二氧基-4(1H)-氧代-香豆素-3-羧酸烷基酯,随后在适当的溶剂中,在碱的存在下,用C.sub.1-C.sub.4烷基卤化物烷基化,然后皂化酯。通过短暂加热和从碱性溶液中沉淀除去少量的2-位置烷基化副产物,留下纯的1-烷基产物。该产品可用于治疗尿路感染。