Reactivity of 5-hydroxy-5,6-dihydro-4H-pyrazines—easy and efficient access to ring-fused polycyclic diazinic systems

Diversity-oriented synthesis of polycyclic diazinic scaffolds

An efficient and versatile synthesis of a polycyclic diazinic system starting from oxazine has been developed using a two-step Michael/retro Michael and cyclization sequence. The substrates were synthesized with good to high yields giving rapid access to molecular diversity.