Synthesis and In Vitro Anti-Inflammatory Activity of Pyrrolo[1,2-A]pyrazines via Pd-Catalyzed Intermolecular Cyclization Reaction

Pyrrolo [1,2-a] pyrazine possessed widely bioactivities due to its particular structure. In this work, three pyrrolo [1,2-a] pyrazines derivatives were synthesized from the 2-bromo-5-methoxypyrazine and propargyl amines or ethers through the Pd-catalyzed intermolecular cycloisomerization strategy. Their structures were characterized by NMR, IR, EI-MS and elemental analysis, and all of them exhibited moderate in vitro anti-inflammatory effects with the inhibitions of 43-59% against IL-6 at 50 μM. The compound 3c revealed relatively good anti-inflammatory activities. The bioactive pyrrolo [1,2-a] pyrazines might be potentially used as anti-inflammatory agents.

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