1.
Angew Chem Int Ed Engl
; 55(1): 392-6, 2016 Jan 04.
Artigo
em Inglês
| MEDLINE
| ID: mdl-26545636
RESUMO
The first total syntheses of the architecturally complex atisane-type diterpenes and biogenetically related atisine-type diterpenoid alkaloids (±)-spiramilactoneâ B, (±)-spiraminol, (±)-dihydroajaconine, and (±)-spiraminesâ C andâ D are reported. Highlights of the synthesis include a late-stage biomimetic transformation of spiramilactoneâ B, a facile formal lactone migration from the pentacyclic skeleton of spiramilactoneâ E, a highly efficient and diastereoselective 1,7-enyne cycloisomerization to construct the functionalized tetracyclic atisane skeleton, and a tandem retro-Diels-Alder/intramolecular Diels-Alder sequence to achieve the tricyclo[6.2.2.0] ring system.