Compounds of the formula I ** Formula ** wherein A1 represents N or CR1, A2 represents N or CR2, A3, A4, A5, A6； respectively independently of each other, represent N or CR3, X is absent or represents unbranched or branched alkylene with 1-10 C atoms, where 1-7 H atoms can be replaced by OH, F and / or by Cl, and / or where one or two non-contiguous CH and / or CH2 groups may be replaced by O, N, NH, NA ', CO, S, SO, SO2, OCO, NHCONH, NHCO, NHSO2, COO, CONH and / or by groups CH>； = CH, or cycloalkylene with 3-7 C atoms, L2 is absent or represents unbranched or branched alkylene with 1-10 C atoms, where 1-7 H atoms can be replaced by OH, F and / or Cl, and / or where one or two non-contiguous CH and / or CH2 groups can be replaced by O, N, NH, NA ', CO, S, SO, SO2, OCO, NHCONH, NHCO, NHSO2, COO, CONH and / or by groups CH>； = CH, or cycloalkylene with 3-7 C atoms, with the proviso that X and L2 cannot be absent at the same time, R represents H or alkyl unbranched or branched with 1-10 C atoms, where 1-7 atto mos of H can be replaced by F and / or Cl, and / or where one or two non-contiguous CH and / or CH2 groups can be replaced by O, N, NH, NA ', CO, S, SO, SO2 , OCO, NHCONH, NHCO, NHSO2, COO, CONH and / or by groups CH>； = CH, or cyclic alkyl with 3-7 C atoms, R1 represents H or unbranched or branched alkyl with 1-10 C atoms, wherein 1-7 atoms of H can be replaced by F and / or by Cl and / or where one or two non-contiguous CH and / or CH2 groups can be replaced by O, N, NH, NA ', CO, S , SO, SO2, OCO, NHCONH, NHCO, NHSO2, COO, CONH and / or by groups CH>； = CH, or cyclic alkyl with 3-7 C atoms, R2 represents H or unbranched or branched alkyl with 1-10 C atoms, where 1-7 H atoms can be replaced by F and / or Cl and / or where one or two non-contiguous CH and / or CH2 groups can be replaced by O, N, NH, NA ' , CO, S, SO, SO2, OCO, NHCONH, NHCO, NHSO2, COO, CONH and / or by groups CH>； = CH, or cyclic alkyl with 3-7 C atoms, R3 represents H or alkyl or unb
