海洋生物碱2,3-二羟基-10-溴吲哚[3,2-a]咔唑的简易合成

Facile synthesis of marine alkaloid 2,3-dihydroxyl-10-bromoindolo[3,2-a]carbazole

2,3-二羟基-10-溴吲哚[3,2-a]咔唑(1)是一种从海绵体中提取的具有多种潜在生物活性的天然海洋生物碱.本文作者以3,6-二溴吲哚(2)与5,6-二乙酰氧基吲哚(3)为原料,经过酸催化偶联、分子间成环两步关键反应构建吲哚[3,2-a]咔唑母核;所构建的吲哚[3,2-a]咔唑母核在碱性条件下水解脱去酚羟基上的酯基,即得到目标化合物1,总收率为48%.

2,3-dihydroxy-10-bromoindolo[3,2-a ]carbazole （1）is a natural marine alkaloid iso-lated from a marine sponge possessing a variety of potent biological activities.With 3,6-dibro-moindole （2）and 5,6-diacetoxyindole （3）as the starting materials,indolo [3,2-a ]carbazole framework is constructed through acid promoted coupling reaction and intermolecular cycliza-tion,the two key steps for construction of the framework.Resultant indolo[3,2-a ]carbazole framework is hydrolyzed under alkaline condition to eliminate the ester group in phenolic hy-droxyl group affording the target compound 1 with an overall yield of 48%.