Total syntheses of lyconadins A-C.
J Am Chem Soc
; 135(8): 3243-7, 2013 Feb 27.
Article
en En
| MEDLINE
| ID: mdl-23330605
ABSTRACT
The total synthesis of the Lycopodium alkaloid lyconadin A was accomplished and it was applied to the total syntheses of the related congeners, lyconadins B and C. Lyconadin A has attracted attention as a challenging target for total synthesis due to the unprecedented pentacyclic skeleton. Our synthesis of lyconadin A features a facile construction of the highly fused tetracyclic skeleton through a combination of an aza-Prins reaction and an electrocyclic ring opening, followed by formation of a C-N bond. Transformation of the bromoalkene moiety of the tetracycle to a key enone intermediate was extensively investigated, and three methods via sulfide, oxime, or azide intermediates were established. A pyridone ring was constructed from the key enone intermediate to complete the synthesis of lyconadin A. A dihydropyridone ring could also be formed from the same enone intermediate, leading to a synthesis of lyconadin B. Establishment of the conditions for an electrocyclic ring opening without formation of the C-N bond resulted in completion of the total synthesis of lyconadin C.
Texto completo:
1
Colección:
01-internacional
Banco de datos:
MEDLINE
Asunto principal:
Compuestos Policíclicos
Idioma:
En
Revista:
J Am Chem Soc
Año:
2013
Tipo del documento:
Article
País de afiliación:
Japón