Finally, our group recently applied PAL to identify the binding partners of the NP falcarinol.106 Falcarinol and the related NP stipudiol are extracted from vegetables and have been reported to have anti-cancer properties, but falcarinol is also known to alkylate nucleophiles and isolated proteins.107 Heydenreuter et al. synthesised the NP 51, alkynylated probe 52 and an alkynylated version of the oxidised NP falcarinone 53 (Fig. 16b).106In situ labelling in A549 cancer cells revealed a prominent band that was identified by gel-based proteomics as aldehyde dehydrogenase 2 (ALDH2). The gene discussed is ALDH2; the disease is cancer.