Reaction SMILES: [NH2:1][C@H:2]([C:18]([O:20][CH3:21])=[O:19])[CH2:3][CH2:4][CH2:5][CH2:6][NH:7][C:8]([O:10][CH2:11][C:12]1[CH:17]=[CH:16][CH:15]=[CH:14][CH:13]=1)=[O:9].CO[CH:24]1[CH2:28][CH:27](OC)[CH2:26]O1>>[CH2:11]([O:10][C:8]([NH:7][CH2:6][CH2:5][CH2:4][CH2:3][C@H:2]([N:1]1[C:24]2[CH:4]=[CH:3][CH:2]=[CH:18][C:28]=2[C:27]2[C:26]1=[CH:27][CH:28]=[CH:24][CH:26]=2)[C:18]([O:20][CH3:21])=[O:19])=[O:9])[C:12]1[CH:17]=[CH:16][CH:15]=[CH:14][CH:13]=1
Reactant: COC(=O)[C@@H](N)CCCCNC(=O)OCc1ccccc1
Reactant: COC1COC(OC)C1
Product: COC(=O)[C@H](CCCCNC(=O)OCc1ccccc1)n1c2ccccc2c2ccccc21

Procedure:
The novel photoreactive carbazole (Cbz)-based monomers of formula I according to the invention can be prepared as depicted in Schemes 1-4 (depicted hereinafter just before the Claims) and described in detail in Examples 1-4. Thus, Scheme 1 depicts the multi-step synthesis of Compound 7, (S) 6-(4-benzoyl-benzoylamino)-2-carbazol-9-yl-hexanoic acid, the photoreactive carbazole (Cbz)-based oxidizable monomer of formula I wherein the oxidizable group is carbazole, the moiety of the chemically reactive group is OH, the linker Y is —HN—CO—, Y′ is absent, the photoreactive moiety is benzophenone, n is 4 and m is 0. Compound 7 was obtained as a white solid in 98% yield. As shown in Example 1 and Scheme 1, protected L-Lys(Z)—OMe (1) is reacted with 2,4-dimethoxytetrahydrofuran (DMTHF) to give (S)-methyl 6-benzyloxycarbonylamino-2-carbazol-9-yl-hexanoate (3), followed by the removal of the benzyloxycarbonyl protecting group with 10% Pd/C to give (S)-6-amino-2-carbazol-9-yl-hexanoic methyl ester (4), In order to obtain (S)-6-(4-benzoyl-benzoylamino)-2-carbazol-9-yl-hexanoic acid methyl ester (6), compound 4 is reacted with 4-benzoyl benzoic acid (5) either by method A, which involves reaction in the presence of carbonyldiimidazole (CDI), or by method B in the presence of PCl5. The desired monomer 7 was obtained by refluxing under methanolic KOH, followed by neutralization to pH 3-4. Scheme 2 and Example 2 and show the synthesis of the Compound 14, (S)-6-(4-azido-benzoylamino)-2-carbazol-9-yl-hexanoic acid, the monomer of formula I wherein the oxidizable group is carbazole, the moiety of the chemically reactive group is OH, the linker Y is —HN—CO—, Y′ is absent, the photoreactive moiety is 4-azido phenyl, n is 4 and m is 0, starting from 4-aminobenzoic acid and resulting in 88% yield of monomer 14. Scheme 3 and Example 3 describe the synthesis of Compound 20, (S)-4-(2-(4-azidobenzoyloxy)ethoxy)-2-(9H-carbazol-9-yl)-4-oxobutanoic acid, the monomer of formula I wherein the oxidizable group is carbazole, the moiety of chemically reactive group is OH, the linker Y is —CO—O—, Y′ is —O—CO—, the photoreactive moiety is 4-azido phenyl, n is 1 and m is 2, starting from H-Asp-O-benzyl. Scheme 4 and Example 4 show the synthesis of Compound 26, (S)-5-(2-(4-azidobenzoyloxy)ethoxy)-2-(9H-carbazol-9-yl)-5-oxopentanoic acid, the monomer of formula I wherein the oxidizable group is carbazole, the moiety of chemically reactive group is OH, the linker Y is —CO—O—, Y′ is —O—CO—, the photoreactive moiety is 4-azido phenyl, n is 2 and m is 2, starting from H-Glu-O-benzyl. Other compounds of formula I can be obtained in similar manner starting from the appropriate starting compounds.