Access to novel imidazo[1,5-a]pyrazine scaffolds by the combined use of a three-component reaction and a base-assisted intramolecular cyclization.
نویسندگان
چکیده
A novel and practical two-step approach to an intriguing class of imidazo[1,5-a]pyrazines with exocyclic C=X (X = CH2, O) bonds is described. The process utilizes a sequential three-component reaction 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 base-promoted cyclization.
منابع مشابه
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عنوان ژورنال:
- Organic & biomolecular chemistry
دوره 12 26 شماره
صفحات -
تاریخ انتشار 2014