Daphnioldhamine A, the first Daphniphyllum alkaloid with transannular effect, easily tautomerized under acidic or alkaline conditions, was isolated from the fruits of Daphniphyllum oldhami. The structure was elucidated by spectroscopic and computational approaches and chemical transformation. A plausible biosynthetic pathway of daphnioldhamine A was also proposed. (C) 2012 Elsevier Ltd. All rights reserved.