Magnesiate Addition/Ring-Expansion Strategy To Access the 6-7-6 Tricyclic Core of Hetisine-Type C20-Diterpenoid Alkaloids.
Org Lett
; 19(17): 4632-4635, 2017 09 01.
Article
em En
| MEDLINE
| ID: mdl-28820600
ABSTRACT
A synthetic strategy to access the fused 6-7-6 tricyclic core of hetisine-type C20-diterpenoid alkaloids is reported. This strategy employs a Diels-Alder cycloaddition to assemble a fused bicyclic anhydride intermediate, which is elaborated to a vinyl lactone-acetal bearing an aromatic ring in five steps. Aromatic iodination is followed by magnesium-halogen exchange with a trialkyl magnesiate species, which undergoes intramolecular cyclization. Subsequent oxidation provides the desired 6-7-6 tricyclic diketoaldehyde, with carbonyl groups at all three positions for eventual C-N bond formation and subsequent elaboration.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Alcaloides
Idioma:
En
Ano de publicação:
2017
Tipo de documento:
Article