Download PDF
Synfacts 2015; 11(1): 0010
DOI: 10.1055/s-0034-1379677
Synthesis of Natural Products and Potential Drugs
© Georg Thieme Verlag Stuttgart · New York

Total Synthesis of (+)-Dihydroperaksine-17-al, (+)-Dihydroperaksine, and (+)-Peraksine

Contributor(s):
Erick M. Carreira
,
Adrien Joliton
Edwankar RV, Edwankar CR, Deschamps JR, Cook JM * University of Wisconsin–Milwaukee and Naval Research Laboratory, Washington, D.C., USA
General Strategy for Synthesis of C-19 Methyl-Substituted Sarpagine/Macroline/Ajmaline Indole Alkaloids Including Total Synthesis of 19(S),20(R)-Dihydroperaksine, 19(S),20(R)-Dihydroperaksine-17-al, and Peraksine.

J. Org. Chem. 2014;
79: 10030-10048
CrossrefGoogle Scholar
Further Information

Publication History

Publication Date:
15 December 2014 (online)

 
 PDF Download Permissions and Reprints

Key words

sarpagine alkaloids - peraksine - haloboration - palladium catalysis - vinylation

Significance

The sarpagine alkaloids (+)-19(S),20(R)-dihydroperaksine-17-al, (+)-19(S),20(R)-dihydropraksine (both isolated from Rauwolfia serpentina) and (+)-peraksine (isolated from Rauwolfia perakensis) have in common the structural feature of a β-methyl group at C-19. Cook and co-workers report the first enantio- and stereospecific synthesis of all three alkaloids.


#

Comment

After introduction of the chiral methyl group by N-alkylation, the pentacyclic core was formed by haloboration followed by a palladium-catalyzed intramolecular α-vinylation of the ketone. Common intermediate F was then converted into (+)-peraksine, (+)-dihydroperaksine-17-al, and (+)-dihydropraksine by a specific acetal protection and hydroboration–oxidation sequence.


#
#


   Permissions and Reprints