Studies On Strigolactone Bc-Ring Formation: Chemical Conversion Of An 18-Hydroxycarlactonoate Derivative Into Racemic 4-Deoxyorobanchol/5-Deoxystrigol Via The Acid-Mediated Cascade Cyclization

Strigolactones are a group of apocarotenoids known as rhizosphere semiochemicals and phytohormones. Canonical strigolactone consists of a tricyclic lactone (ABC-rings) and a butenolide moiety (D-ring). Although strigolactone biosynthesis has been extensively studied, the process of BC-ring formation has not been elucidated to date. In this study, the chemical conversion of an 18-hydroxycarlactonoate derivative into racemic 4-deoxyorobanchol/5-deoxystrigol was achieved by the acid-mediated cascade cyclization. The acid-mediated BC-ring formation may offer inspiring suggestion for the currently unclear BCring formation in strigolactone biosynthesis. (C) 2021 Elsevier Ltd. All rights reserved.