| CPC A61K 47/6849 (2017.08) [A61K 47/68031 (2023.08); A61K 47/6889 (2017.08); C07F 9/4015 (2013.01); C07F 9/4071 (2013.01)] | 11 Claims |

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1. A compound of formula (III)
![]() wherein
represents a bond and X represents (R3 R4)C, wherein R3 and R4 independently represent H or C1-C8-alkyl; or represents a double bond and X represents R3C, wherein R3 represents H or C1-C8-alkyl; andY represents S;
R1 represents an optionally substituted aliphatic or aromatic residue;
represents an aliphatic or aromatic residue; and represents an amino acid, a peptide, a protein, an antibody, or a nucleotide. |