申请人:Lonza, Ltd.
公开号:US05446159A1
公开(公告)日:1995-08-29
A process for preparing imidazopyridines of the general formula: ##STR1## wherein R.sub.1 is an alkyl, cycloalkyl, aryl or aralkyl group or is a heterocyclic radical, R.sub.2 and R.sub.4 are identical or different and are hydrogen, a hydroxy, a cyano, alkyl, cycloalkyl, aryl or aralkyl group or are an alkanoyl or an alkoxy-carbonyl group, and R.sub.3 is hydrogen, an alkyl, aryl or aralkyl group or a halogen atom. In the key step of the process, an amidine of the formula: ##STR2## is cyclized with a 1,3-dicarbonyl compound of the general formula: ##STR3## The imidazopyridines are valuable intermediates for the preparation of angiotensin II antagonists.
一种制备通式为:##STR1##的咪唑吡啶化合物的方法,其中R.sub.1是烷基、环烷基、芳基或芳基烷基或是杂环基,R.sub.2和R.sub.4相同或不同,可以是氢、羟基、氰基、烷基、环烷基、芳基或芳基烷基,也可以是烷酰基或烷氧羰基,而R.sub.3是氢、烷基、芳基或芳基烷基或卤素原子。在该方法的关键步骤中,通式为:##STR2##的胺二酮与通式为:##STR3##的1,3-二羰基化合物发生环化反应。这些咪唑吡啶化合物是制备血管紧张素II拮抗剂的有价值的中间体。