Synthesis of a tyrosinase inhibitor by consecutive ethenolysis and cross-metathesis of crude cashew nutshell liquid

• Jacqueline Pollini,
• Valentina Bragoni and
• Lukas J. Gooßen

Beilstein J. Org. Chem. 2018, 14, 2737–2744, doi:10.3762/bjoc.14.252

• Jacqueline Pollini Valentina Bragoni Lukas J. Goossen Lehrstuhl für Organische Chemie I, Ruhr-Universität Bochum, ZEMOS, Universitätsstraße 150, 44801 Bochum, Germany 10.3762/bjoc.14.252 Abstract A convenient and sustainable three-step synthesis of the tyrosinase inhibitor 2-hydroxy-6

• subsequent hydrogenation step. Overall, the target compound was obtained in an overall yield of 61% based on the unsaturated anacardic acid content and 34% based on the crude CNSL. Keywords: cashew nutshell liquid; cross-metathesis; renewable feedstock; sustainable chemistry; tyrosinase inhibitor

• synthesis of the most potent tyrosinase inhibitor among them, the ginkgolic acid (13:0), starting from crude CNSL (Scheme 1, left). Tyrosinase is an enzyme [28] which is responsible for browning of fruits and vegetables as well as skin pigmentation [29]. Furthermore, it is linked to several