Halichondrin B: Synthesis of the C(1)−C(15) Subunit

Autor:	S D, Burke, K W, Jung, W T, Lambert, J R, Phillips, J J, Klovning
Rok vydání:	2000
Předmět:	Models Molecular Magnetic Resonance Spectroscopy Ethers Cyclic Organic Chemistry Molecular Conformation Antineoplastic Agents Indicators and Reagents Macrolides
Zdroj:	The Journal of Organic Chemistry. 65:4070-4087
ISSN:	1520-6904 0022-3263
DOI:	10.1021/jo000140r
Popis:	A short and efficient synthesis of the C(1)-C(15) subunit of halichondrin B in its natural configuration is described. The polycyclic caged ketal 3, containing nine asymmetric centers, is prepared in 14 steps from alpha-D-glucoheptonic acid gamma-lactone (7). Key steps in the two similar routes described include EtMgBr-promoted pinacol ring expansions of hydroxy mesylates 23 and 34, intramolecular Michael additions of 29 and 37, and a one-pot, HF-induced conversion of 4 to 3involving in situ silyl ether cleavage, acetal hydrolysis, Michael addition, and caged ketal formation. Alternative protocols for carbinol inversion at C(11), one early and one late in the synthetic sequence, are also described.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_dedup___::7c3a8fce8e61de227237ad85039b6461 https://doi.org/10.1021/jo000140r Zobrazit plný text záznamu