Total synthesis of the Securinega alkaloid (-)-secu'amamine A.
The first enantioselective total synthesis of the rearranged Securinega alkaloid (-)-secu'amamine A is reported starting from D-proline as the source of absolute chirality. The synthesis requires 15 steps starting from D-proline-derived N-trityl aldehyde 11 and proceeds in approximately 9% overall yield. Key steps include a stereoselective conjugate addition of pyrrolidino enedione 19 to afford indolizidine 24 as the major product and cyclization/lactonization of diketoester 25 to produce tetracycle 26. In addition, 1H NMR NOE studies and X-ray analysis on the synthetic alkaloid have established that the indolizidine moiety is trans-fused.
Liu
Peng
P
Department of Chemistry, Pennsylvania State University, University Park, Pennsylvania 16802, USA.
Hong
Sungwoo
S
Weinreb
Steven M
SM
D000470:Alkaloids / Q000138:chemical synthesis*; D019665:Euphorbiaceae; D006572:Heterocyclic Compounds, Bridged-Ring / Q000138:chemical synthesis*; D008722:Methods
D000470:Alkaloids; D006572:Heterocyclic Compounds, Bridged-Ring; C519982:secu'amamine A