Access to novel imidazo[1,5-a]pyrazine scaffolds by the combined use of a three-component reaction and a base-assisted intramolecular cyclization
作者:Orazio A. Attanasi、Gianfranco Favi、Gianluca Giorgi、Roberta Majer、Francesca Romana Perrulli、Stefania Santeusanio
DOI:10.1039/c4ob00676c
日期:——
A novel and practical two-step approach to an intriguing class of imidazo[1,5-a]pyrazines with exocyclic CX (X = CH2, O) bonds is described. The process utilizes a sequentialthree-componentreaction of propargyl amine or aminoester, 1,2-diaza-1,3-dienes and isothiocyanates to furnish functionalized 2-thiohydantoins which are transformed into thiohydantoin-fused tetrahydropyrazines by subsequent regioselective
描述了一种新颖实用的两步方法,用于合成具有环外C X(X = CH 2,O)键的咪唑并[1,5- a ]吡嗪类。该方法利用炔丙胺或氨基酯,1,2-二氮杂-1,3-二烯和异硫氰酸酯的三组分顺序反应来提供官能化的2-硫代乙内酰脲,其通过随后的区域选择性碱基促进的环化作用转化成硫代乙内酰脲-融合的四氢吡嗪。