“…Pyridine fragments are used in drugs due to their specific characteristics such as basicity, hydrogen bond forming ability, water solubility, and especially because of pyridine rings are bioisosteres of amines, amides, N-heterocyclic rings and benzene rings [1][2][3][4][5]. A special type of pyridine, the 4-pyridones, is also fairly well represented among drugs [5][6][7][8][9][10][11][12]. Some of bioactive compounds, such as ciprofloxacin, levofloxacin, delafloxacin, and elvitegravir, contain the fragment of 4-oxo-1,4-dihydropyridine-3-carboxylic acid [6,8] and some others, ivacaftor, dolutegravir, bictegravir, aspernigrin B, and 4PYR, contain the fragment of 4-oxo-1,4-dihydropyridine-3-carboxamide [5][6][7].…”