The present invention relates to a compound represented as formula (I): ##STR1##

wherein

• A is R2-N(R3R4), ##STR2##

  wherein Ar is a substituted or unsubstituted phenyl group, m is an integer between 0 to 4, Het is a substituted or unsubstituted 4 to 8 member heterocyclic group, n is an integer between 0 to 4; R₃ and R₄ are independently H, ##STR3##

  or ##STR4##

  R₂ is ##STR5## ##STR6## ##STR7## ##STR8##

  or ##STR9##

  wherein X is (CH₂)_y—Ar, R₆, or (CH₂)_z-Het, wherein Ar is a substituted or unsubstituted phenyl group, y is an integer between 0 to 2, R₆ is a substituted or unsubstituted linear or a branched C_1-10 alkyl group, z is an integer between 0 to 2, and Het is a 6 to 12 member heterocyclic group;

• B is OR₁ or ##STR10##

  wherein R₁ is H or C_2-5 alkyl group.