Journal Article

Total synthesis of the Daphniphyllum alkaloid daphenylline

Li, Yong, Li, Ang, Lu, Zhaoyong, Deng, Jun

2013

نظرة عامة

The Daphniphyllum alkaloids are a large class of natural products isolated from a genus of evergreen plants widely used in Chinese herbal medicine. They display a remarkable range of biological activities, including anticancer, antioxidant, and vasorelaxation properties as well as elevation of nerve growth factor. Daphenylline is a structurally unique member among the predominately aliphatic Daphniphyllum alkaloids, and contains a tetrasubstituted arene moiety mounted on a sterically compact hexacyclic scaffold. Herein, we describe the first total synthesis of daphenylline. A gold-catalysed 6- exo -dig cyclization reaction and a subsequent intramolecular Michael addition reaction, inspired by Dixon's seminal work, were exploited to construct the bridged 6,6,5-tricyclic motif of the natural product at an early stage, and the aromatic moiety was forged through a photoinduced olefin isomerization/6 π -electrocyclization cascade followed by an oxidative aromatization process. Daphenylline is an alkaloid containing a tetra-substituted arene within a sterically compact hexacyclic scaffold. Here, the first total synthesis of daphenylline is described. A gold-catalysed 6- exo -dig cyclization reaction was exploited to construct the bridged 6,6-bicycle at an early stage, the aromatic moiety was forged through a photoinduced olefin isomerization/6 π electrocyclization cascade followed by oxidative aromatization.

• الناشر: Nature Publishing Group UK,Nature Publishing Group
• موضوع: 639/638/403/937 / Alkaloids - chemical synthesis / Analytical Chemistry / Antioxidants / Biochemistry / Catalysis / Chemistry / Chemistry/Food Science / Gold / Herbal medicine / Inorganic Chemistry / Natural products / Organic Chemistry / Physical Chemistry / Saxifragaceae - chemistry