2-Amino-substituted 6,7-dimethoxy-4-trifluoromethyl-quinolines were synthesized from the 2-oxo compound 1 via 2-chloroquinoline 2 and aminated with anilines or benzylamine to give highly fluorescent molecules 4, 5. 2-Aminoquinoline 8 was obtained via azidation of 2 to 6, reaction to the phosphazene 7, and hydrolysis. 4-Ethoxycarbonyl derivative 4b is suitable for linking appropriate biomolecules. The construction of a linking group was achieved by conversion of 4b via carboxylic acid 9 to the reactive O-succinimide ester 10, which reacts easily with amino acids or peptides to amides 11 and 12. The fluorescent properties were investigated and are comparable with derivatives of 1.
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