| abstract |
The invention relates to compounds of formula (I) wherein, among other values, A is -O- or> N-R6; each of R1 and R4 is methyl, methoxy, ethoxy or OH; R2 is trimethylene; R3 is H or methyl; R5 is (R9-A'-C -) - R10-; X1 is defined as R1 or (R27) 3siO-; X2 is H, C1-C8 alkyl or (R27) 3Si-; m and n are numbers from 1 to 50 and, if m + n is a number from 3 to 10, X1 and X2 can also form a direct bond together. |