New asymmetric routes to ajmaline and suaveoline indole alkaloids
作者:Patrick D. Bailey、Keith M. Morgan、David I. Smith、John M. Vernon
DOI:10.1039/b005694o
日期:——
The tetracyclic advanced intermediates 6, 8 and 9 obtained from L-tryptophan via a cis-selective Pictet–Spengler reaction and a Dieckmann–Thorpe cyclisation are used in a range of new approaches to polycyclic monoterpenoid indole alkaloids such as ajmaline and suaveoline. Structural modifications designed to facilitate a key intermolecular addition to C15 (ajmaline numbering) are described, followed by two intramolecular routes based on the addition of a suitable carbon fragment to a remote nitrogen atom prior to bond formation at C15.