The synthesis of the BCDE-tetracyclic core of (-)-cephalotaxine has been achieved in eight steps starting from N-Boc-L-proline methyl ester. An alkylidene carbene 1,5-CH insertion reaction was used as a key step in the stereocontrolled synthesis of the DE-spirocyclic fragment and an intramolecular H
Studies towards the total synthesis of novel marine diterpene havellockate. Construction of the tetracyclic core
โ Scribed by Goverdhan Mehta; R.Senthil Kumaran
- Publisher
- Elsevier Science
- Year
- 2001
- Tongue
- French
- Weight
- 73 KB
- Volume
- 42
- Category
- Article
- ISSN
- 0040-4039
No coin nor oath required. For personal study only.
โฆ Synopsis
The synthesis of the tetracyclic core present in the novel marine diterpenoid havellockate 1 has been accomplished from the readily available endo-dicyclopentadienone-10-ethylene ketal 3 as a prelude to the projected total synthesis of the natural product.
๐ SIMILAR VOLUMES
An oxy-Cope protocol has been grafted on to a previously crafted hydroazulenic system to provide a facile entry into the 5,11-fused bicyclic skeleton present in the novel neodolabellane diterpenoids. Formation of a novel tricyclic diterpenoid framework, generated through a transannular cyclization i
The pyrido[3%,2%:4,5]pyrrolo [1,2-c]pyrimidine core structure of the variolins has been synthesized in three steps from commercially available materials. The key reaction involves the deoxygenation and concomitant cyclization of a triarylmethanol using the combination of triethylsilane and trifluoro
A concise annulation-fragmentation strategy has been elaborated for the construction of the bridged nine-membered ring ether moiety of the eunicelline diterpenes. Key steps are a SmI:-induced Barbier cyclization and an oxidative ring fission using cerium(IV) ammonium nitrate (CAN)