Reducing disaccharides and their 1,2-dicarbonyl intermediates as building blocks for nitrogen heterocycles
作者:Andreas Brust、Eckehard Cuny
DOI:10.1039/c3ra47349j
日期:——
The existential importance of a sustainable economy necessitates the utilisation of plant based renewable resources such as lignin and carbohydrates. Carbohydrate utilization as industrial raw materials requires low environmental impact conversions from sugars to high value products. Here we present the conversion of reducing disaccharides into industrially relevant heterocycles of the quinoxaline-, 1,2,4-triazine-, pyrazine- and pyrazolo[3,4-b]quinoxaline-type. Heterocycle formation was facilitated by chemical conversion of reducing sugars into 1,2-dicarbonyl intermediates and their subsequent cyclization with nitrogen bis-nucleophiles. A range of disaccharides was converted into quinoxalines carrying a diverse glycosylation pattern on the polyhydroxy alkyl side chain. All transformations were performed without the need of protecting group chemistry.
可持续经济的重要性决定了必须利用木质素和碳水化合物等植物性可再生资源。要将碳水化合物用作工业原料,就必须将糖类转化为高价值产品,而这种转化过程对环境的影响较小。在此,我们介绍了将还原性二糖转化为与工业相关的喹喔啉、1,2,4-三嗪、吡嗪和吡唑并[3,4-b]喹喔啉型杂环的过程。通过将还原糖化学转化为 1,2-二羰基中间体并随后与氮双亲核物环化,促进了杂环的形成。一系列二糖被转化成喹喔啉,其多羟基烷基侧链上的糖基化模式多种多样。所有转化过程都无需保护基化学反应。