N-Heterocyclic scaffolds

Gracias V, Moore JD, Djuric SW (2004) Sequential Ugi/Heck cyclization strategies for the facile construction of highly functionalized N-heterocyclic scaffolds. Tetrahedron Lett 45 417 20... 

Langer and coworkers constructed diverse O- and N-heterocyclic scaffolds, such as Y-alkylidene-a-hydroxybutenolides and pyrrolo[3,2-ii]pyrrol-2,5-diones, exploiting the well-established cyclization strategy of bisnucleophiles with oxalic add derivatives [163], while Stockman s research group reported in this context on a novel oxime formation/Michael addition providing the structural core of the alkaloid perhydrohistrionicotoxin [164]. 

Stowers KJ, Fortner KC, Sanford MS (2011) Aerobic Pd-catalyzed sp3 C-H olefination a route to both N-heterocyclic scaffolds and alkenes. J Am Chem Soc 133(17) 6541-6544... 

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