Viminalins A-O: Diverse [3+2] hybrids of acylphloroglucinol and α-phellandrene from the fruits of Callistemon viminalis

Fifteen new adducts of acylphloroglucinol and monoterpene (α-phellandrene) featured a 2,3-dihydrobenzofuran core were isolated from the fruits of Callistemon viminalis. An oxidative [3+2] cycloaddition between acylphloroglucinol and monoterpene was speculated as the key step in the biosynthetic pathway.192