200411-10-5Relevant academic research and scientific papers
A concise total synthesis of the azaphenanthrene alkaloid eupolauramine
Hoarau, Christophe,Couture, Axel,Cornet, Helene,Deniau, Eric,Grandclaudon, Pierre
, p. 8064 - 8069 (2007/10/03)
A six-step total synthesis of the azaphenanthrene alkaloid eupolauramine 1 has been achieved using combinational metalation-cyclization tactics. The synthetic route involved first the construction of the azaisoindolinone 9 by aryne-mediated cyclization of he phosphorylated pyridocarboxamide 7 and subsequent dephosphorylation. Metalation of 9 followed by connection of the hydroxybenzyl appendage and E1CB anti-elimination allowed the formation of the halogenoarylmethylene azaisoindolinone 4 in the exclusive E-form. Oxidative radical cyclization gave rise to the azaphenanthrene skeleton and regioselective bromination of 3 induced the incorporation of the bromine atom at the 6-position of the azaphenanthrene lactam. Ultimate replacement of the bromine atom of 2 by the methoxy functionality by sequential transmetalation, in situ oxidation, and O-methylation of the phenolic derivative 14 completed the synthesis of the target natural product eupolauramine.
A short and efficient synthesis of 3-diphenylphosphoryl- and 3-diethoxyphosphoryl(aza)isoindolinones: Extension to the sulfonylated analogs
Couture, Axel,Deniau, Eric,Woisel, Patrice,Grandclaudon, Pierre
, p. 1439 - 1445 (2007/10/03)
A variety of 3-diphenylphosphoryl- and 3-diethoxyphosphoryl(aza)isoindolinones have been efficiently prepared by aryne- and hetaryne-mediated cyclization of phosphorylated α-amino carbanions derived from suitably substituted 2- and 3-halobenzamide and 3-chloropyridine-4-carboxamide derivatives. The synthesis of some 3-sulfonylated analogs by extension of this principle has been achieved.
