NHC*-Gold(I) Bioconjugated to Carbohydrates and Peptides as Targeted Anticancer Drugs

Targeted delivery of potent cytotoxic drugs to cancer cells minimizes systemic toxicity and potentially avoids side effects. NHC*-Au-Cl has already been proven to be a potent anticancer agent based on the stabilising and lipophilic properties of the 1,3-dibenzyl-4,5-diphenyl-imidazol-2-ylidene (NHC*) ligand. One possibility is the chemoselective thiosugar conjugation to NHC*-Au-Cl in order to have active uptake of the resulting NHC*-Au-SR primarily into tumour tissue through the Warburg effect. In addition, a strategy based on chemoselective cysteine conjugation of NHC*-Au-Cl to human serum albumin or Trastuzumab to potentiate drug-ligand ratio, pharmacokinetics, as well as drug efficacy and safety is presented. These strategies are essential steps forward towards the use of gold-based anticancer agents as targeted therapies.