The invention relates to a compound chosen from dyes of azomethine type bearing a pyrazolopyridine unit of formula (I) and the leuco forms thereof of formula (II) below, and also the optical isomers and geometrical isomers thereof, the tautomers thereof, the addition salts thereof with an acid or a base, and the solvates thereof. The invention also relates to the use of these particular compounds for dyeing keratin fibers.