The invention relates to the use of compounds corresponding to formula (I) in which R2 and R3 together form, with the carbon atoms of the phenyl nucleus to which they are attached, a 6-membered nitrogenous heterocycle corresponding to one of the formulae (A), (B) and (C) in which the wavy lines represent the phenyl nucleus to which R2 and R3 are attached, or of a pharmaceutically acceptable salt thereof, for preparing a medicament for the treatment of bladder cancer.
