| abstract |
The invention relates to new compounds of the general formula <IMAGE> (I) <IMAGE> and <IMAGE> (II) where R is a divalent, optionally branched aliphatic, cyclic or alicyclic hydrocarbon group having from 2 to 10 carbon atoms; R1 and R2 are, independently of one another, hydrogen, or aliphatic or aromatic hydrocarbon groups; R3 is -COOH, -CN, -COOC2H4-OH, -CONH-NH2 or -COOR4; R4 is an aliphatic hydrocarbon group having from 1 to 4 carbon atoms; and n is 2 or 3. |