Concise Modular Synthesis of Thalassotalic Acids A–C

The novel N-acyldehydrotyrosine analogues known as thalassotalic acids A–C were isolated from a marine bacterium by Deering et al. in 2016. These molecules were shown to have tyrosinase inhibition activity and thus are an attractive set of molecules for further study and optimization. To this end, a concise and modular synthesis has been devised and executed to produce thalassotalic acids A–C and two unnatural analogues. This synthesis has confirmed the identity and inhibitory data of thalassotalic acids A–C, more potent synthetic analogues (IC₅₀ = 65 μM), and provides a route for further structure–activity relationship studies to optimize these molecules.