[GRAPHICS]A formal synthesis of (-)-apicularen A has been completed. The synthesis features a cyanohydrin acetonide coupling as a convergent approach to the C9-C18 segment and an intramolecular Diels-Alder addition sequence to create both the 10-membered macrocycle and the aromatic ring.
[GRAPHICS]A formal synthesis of (-)-apicularen A has been completed. The synthesis features a cyanohydrin acetonide coupling as a convergent approach to the C9-C18 segment and an intramolecular Diels-Alder addition sequence to create both the 10-membered macrocycle and the aromatic ring.
Total Synthesis and Biological Evaluation of (−)Apicularen A and Analogues Thereof
作者:K. C. Nicolaou、David W. Kim、Rachid Baati、Aurora O′Brate、Paraskevi Giannakakou
DOI:10.1002/chem.200305230
日期:2003.12.15
Apicularen A (1) and related benzolactone acylenamines belong to a growing class of novel natural products possessing highly cytotoxic properties. The challenging structure of 1 includes a 10-membered macrolactone ring, a tetrahydropyran system, an o,m-substituted phenol and a doubly unsaturated acyl group attached on the side chain enamine functionality. The total synthesis of apicularen A described
Complete details of an asymmetric synthesis of apicularen (1) are described. The synthesis has been accomplished using a highly diastereo- and enantioselective [4 + 2] annulation for the assembly of the functionalized pyran core. An underdeveloped lactonization method involving an NaH promoted transesterification of an advanced intermediate bearing an aryl cyanomethyl ester was used for the macrolactonization step.