Another recent example of the application of chemical space to SP(A)R analysis lies at the interface of drug discovery and food chemistry . Bayer et al. explored the associations between the chemical structures of 133 compounds with known biological activities and extra-oral bitter taste receptors, which belong to the superfamily of G-protein-coupled receptors. As part of the analysis, the authors represented the chemical space of the compounds using t-SNE as a visualization tool; the compounds were represented using MACCS key fingerprints. It was observed that the visual representation of chemical space grouped chemical compounds with similar functional groups, even though the compounds can belong to different classes (depending on the type of receptors they are related to).