Aus der Umsetzung von 2-Aminobenzimidazol (1) mit den Malonestern 2a-g gehen die 4-Hydroxypyrimido[1,2-a]benzimidazol-2-one 3a-g hervor, unter denen sich Vertreter mit zentral dämpfenden, hypertreter mit zentral dämpfenden, fundenzi antibakteriellen Eigenschaften finden。
A dye compound represented by the following formula has at least one anionic group:
wherein R
1
and R
2
independently represent an amino or hydroxyl group, A
1
represents nitrogen or CR
4
, R
4
and R
3
form a first aromatic ring, R
3
represents a substituent with a negative Hammett's substituent constant when A
1
represents nitrogen, and Cy represents a second aromatic ring.