Synthesis and photophysics of acridine derivatives

Highly fluorescent acridine derivatives were prepared by a multistep synthe sis starting from 2-chlorobenzoic acid and appropriate (aminophenyl)alkanoi c acid by means of a modified Ullmann-Jourdan reaction followed by cyclodeh ydration step, and by amination in the case of aminoacridine analogues. The obtained derivatives were subjected to photophysical studies (absorption a nd fluorescence). The compounds displayed interesting absorption behavior a nd high quantum yield of fluorescence. The acridine analogues bearing free carboxylic group can serve as effective fluorescent probes in conformation analysis of peptides.