Carbohydrate-N-heterocyclic carbene metal complexes: Synthesis, catalysis and biological studies

N-Heterocyclic carbenes (NHCs) are strong donor ligands that form stable complexes with many metals, making them popular subjects for research in organometallic chemistry. While work with NHCs initially was predominantly in the area of catalysis, applications of NHCs in medicinal chemistry have blossomed in recent years. Chemists are investigating NHC complexes with increasingly complex NHC components, adding novel functional groups to the NHC ring. Amongst possible functional groups, carbohydrates are naturally abundant and well known for their biocompatibility, chirality, water solubility and nontoxicity. It is not surprising that carbohydrate groups have been incorporated into NHC ligands to impose chirality, increase water solubility, and promote biocompatibility. Such novel NHCs and their metal complexes show much promise in catalysis and medicinal chemistry. In this review, we focus on metal complexes that contain both an NHC ligand and a carbohydrate ligand, or have novel NHC ligands bearing pendant carbohydrate groups. We discuss synthesis, structural aspects, catalysis and medicinal chemistry. Roles of the NHC ligand and carbohydrate moiety related to these properties are highlighted. (C) 2017 Elsevier B.V. All rights reserved.