| abstract |
The present invention concerns the use as a fluorescent chromophore of a compound of formula (I) in which: - A 1 is -N- or -C(Y 1 )-; A 2 is -N- or -C(Y 2 )-; A 3 is -N- or -C(Y 3 )-; A 4 is -N- or -C(Y 4 )-; at least one of A 1 , A 2 , A 3 and A 4 representing -N-; - X 1 is -N- or -C(Y 5 )-; X 2 is -N- or -C(Y 6 )-; X 3 is -N- or -C(Y 7 )-; and - Υ 1 , Y 2 , Y 3 , Y 4 , Y 5 , Y 6 and Y 7 are in particular chosen independently of one another from the group consisting of: H, electron-donating groups and electron-withdrawing groups. |