Total Synthesis of Aurantosideâ
G, an N-ß-Glycosylated 3-Oligoenoyltetramic Acid from Theonella swinhoei.
Angew Chem Int Ed Engl
; 55(34): 10122-5, 2016 08 16.
Article
en En
| MEDLINE
| ID: mdl-27304208
ABSTRACT
The first synthesis of a natural N-glycosylated 3-acyltetramic acid is reported. Aurantosideâ
G (1 g), a deep-red metabolite of the marine sponge Theonella swinhoei, is highly delicate in the pure state. It features a chlorinated dodecapentaenoyl side chain at an l-asparagine-derived tetramic acid, the ring nitrogen atom of which is linked to a ß-configured d-xylose. The side chain was built through consecutive Wittig and HWE reactions and used to N-acylate the amino group of an asparaginate that had already been N-xylosylated through a Fukuyama-Mitsunobu reaction. This N-acylation step fixes the ß-configuration of the xylose, which is essential for the antifungal activity, but only if the sugar carries bulky, electron-rich protecting groups such as PMB. In the final step, the heterocycle was closed quantitatively through a basic Lacey-Dieckmann condensation of an entirely unprotected precursor.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Pirrolidinonas
/
Theonella
/
Glicósidos
Límite:
Animals
Idioma:
En
Revista:
Angew Chem Int Ed Engl
Año:
2016
Tipo del documento:
Article
País de afiliación:
Alemania