Nitro-oxyderivative compounds or salts thereof having the following
general formula (I): A--(B).sub.b0--(C).sub.c0--NO.sub.2 wherein: c0 is
an integer and is 0 or 1, b0 is an integer and is 0 or 1, A=R--T.sub.1--,
wherein R is the radical of an analgesic drug for the chronic pain, in
particular for the neuropathic pain; B is such that its precursor is
selected from anminoacids, hydroxyacids, polyalcohols, compounds
containing at least one acid function; C is a bivalent radical containing
an aliphatic, heterocyclic or aromatic radical.