| Autor: |
Yang, Jie, Z. Wearing, Xiangyu, W. Le Quesne, Philip, R. Deschamps, Jeffrey, M. Cook, James |
| Zdroj: |
Journal of Natural Products; July 2008, Vol. 71 Issue: 8 p1431-1440, 10p |
| Abstrakt: |
The first enantiospecific total synthesis of (+)-alstonisine has been accomplished from d-tryptophan methyl ester 13in 12% overall yield (in 17 reaction vessels). A diastereospecific osmylation process has been employed as a key step to convert indole 18into spirocyclic oxindole 19. Mechanistic studies of the stereoselective osmylation of the 2,3-indole double bond of indole alkaloids has been carried out. Compelling evidence for the intramolecular delivery of OsO 4via Nb-complexation was obtained for the osmylation process. The correct structure of (+)-alstonisine ( 1) was determined by NOE spectroscopic experiments and further confirmed by single-crystal X-ray analysis. |
| Databáze: |
Supplemental Index |
| Externí odkaz: |
|
