Synthesis of 6-methyl-3,4-dihydropyrazinones using an Ugi 4-CR/allenamide cycloisomerization protocol.
نویسندگان
چکیده
A synthetic approach to the 6-methyl-3,4-dihydropyrazinone core from Ugi adducts is described. This methodology relies on the regioselective C-N bond formation between an allenamide moiety at C-β and an amide anion formed under base-mediated conditions. This protocol allows easy access to tricyclic systems such as pyrazino[2,1-a]isoindole and pyrazino[2,1-a]isoquinoline nuclei.
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ورودعنوان ژورنال:
- Organic & biomolecular chemistry
دوره 15 2 شماره
صفحات -
تاریخ انتشار 2017