| abstract |
The invention relates to compounds of the formula <IMAGE> (I) in which: A is a divalent radical selected from: A1) -O-CO-A2) -CH2-O-CO-A3) -O-CH2-CO-A4) -O-CH2-CH2-A5) -N(R1)-CO-A6) -N(R1)-CO-CO-A7) -N(R1)-CH2-CH2-A8) -O-CH2-in which: R1 is a hydrogen or a (C1-C4)-alkyl; and Am is a nitrogen-containing heterocycle. |