Efficient approach to the unknown isoxazolo[3,4-d]thieno[2,3-b]pyridine system by regioselective intramolecular nitrone cycloadditions
作者:Gianluigi Broggini、Katja Chiesa、Ivan De Marchi、Michela Martinelli、Tullio Pilati、Gaetano Zecchi
DOI:10.1016/j.tet.2005.01.121
日期:2005.4
An effective approach to the new isoxazolo[3,4-d]thieno[2,3-b]pyridine system was provided by way of an intramolecular nitrone cycloaddition. The required nitrones were built in good yields starting from thiophene-2-carboxylic acids. The same skeleton was achieved in optically active form employing chiral nitrones derived from N-α-methylbenzyl- and the N-α-hydroxymethylbenzyl-hydroxylamines. The absolute
一种新的异恶唑并[3,4- d ]噻吩并[2,3- b ]吡啶系统的有效方法是通过分子内硝酮环加成的。从噻吩-2-羧酸开始,以高收率构建了所需的硝酮。使用衍生自N -α-甲基苄基-和N -α-羟甲基苄基-羟胺的手性硝酮,以旋光形式获得相同的骨架。通过X射线分析确定产物的绝对构型。