“…Moreover, they are versatile synthetic intermediates [225], and many functionalized pyrazines possess pharmacological activities, such as antiviral [226,227] (242, 243), ATR kinase inhibitor [228] (244), antitumor [229], vascular endothelial growth factor inhibitory activity [230], or as epithelial sodium channel blockers [231] (Figure 15). Pyrazine is a six membered hetero-aromatic ring usually found in the structure of numerous natural products and synthetic compounds, some of which are used in the food industry for their flavor properties [222][223][224]. Moreover, they are versatile synthetic intermediates [225], and many functionalized pyrazines possess pharmacological activities, such as antiviral [226,227] (242, 243), ATR kinase inhibitor [228] (244), antitumor [229], vascular endothelial growth factor inhibitory activity [230], or as epithelial sodium channel blockers [231] (Figure 15).…”