Pyrazines and Their Benzo Derivatives

Pyrazine is a six-membered aromatic heterocycle bearing two nitrogen atoms in a 1,4-orientation. Quinoxalines and phenazines are benzo derivatives which have one or two benzene moieties fused to the pyrazine nucleus, respectively. Pyrazines and benzo derivatives possess interesting reactivity profiles and have found a diversity of applications in total synthesis, chemical biology, materials, and medicine.