Synfacts 2007(1): 0003-0003  
DOI: 10.1055/s-2006-955656
Synthesis of Natural Products and Potential Drugs
© Georg Thieme Verlag Stuttgart · New York

Synthesis of (±)-β-Erythroidine

Contributor(s):Philip Kocienski, Fiona Black
Y. He, R. L. Funk*
Pennsylvania State University, University Park, USA
Total Syntheses of (±)-β-Erythroidine and (±)-8-oxo-β-Erythroidine by an Intramolecular Diels-Alder Cycloaddition of a 2-Aminoacrolein
Org. Lett.  2006,  8:  3689-3692  
Further Information

Publication History

Publication Date:
15 December 2006 (online)


Significance

A 13-step synthesis of the erythrinan alkaloid (±)-β-erythroidine is reported. A Diels-Alder cycloadditon, an intramolecular Heck cyclization and an electrocyclic ring closure are employed in the construction of the tetracyclic ring system.

Comment

Upon heating in refluxing toluene, amidoxin D underwent a retrocycloaddition and Diels-Alder cycloaddition to afford F in 66% yield. Ester G was saponified and the corresponding dienoic acid derivative heated in refluxing toluene to effect a 6π-electrocyclic ring closure. Introduction of the C3 oxygen was achieved diastereoselectively with singlet oxygen to give J, which was converted into β-erythroidine in three steps.