Abstract

Bioorthogonal Palladium-Labile Prodrugs for Site-Specific Anticancer Therapy

Asier Unciti-Broceta, IGMM Academic Fellow, University of Edinburgh

The goal of performing bio-independent syntheses in biological environs, so called bioorthogonal chemistry, has inspired the search for novel biocompatible organic reactions for more than a decade and found a niche application as a labelling strategy to study biomolecules in their native state . While metal-free bioorthogonal reactions are considered optimal for living systems due to their biocompatibility, significant progress has been made in recent years by our group and others in the development of cell-tolerated bioorthogonal organometallic (BOOM) reactions, opening up new avenues for the exploitation of the bioorthogonal paradigm. However, the potential of such selective processes in medicine is yet to be determined. Based on the biocompatibility of metallic palladium (widely used, e.g., in dental restoration and jewelry) and its remarkable catalytic properties, our group investigates the use of heterogeneous palladium catalysis to enable site-specific conversion of cytotoxic prodrugs into its active form. As opposed to biolabile prodrugs, whose activation process relies on metabolic pathways, an efficient Pd0-activated prodrug therapy would be entirely dependent on the distinct catalytic properties of this metal and therefore the prodrug would remain intact in the absence of a Pd0 source. In this talk I will present the discovery of two palladium-mediated deprotections that take place under biocompatible conditions and their application as masking methods to suppress the activity of chemotherapeutic drugs, while enabling the bioorthogonal rescue of the drugs’ pharmacological properties by heterogeneous palladium chemistry in cancer cell culture.