Synthesis of the C3-C19 segment of phorboxazole B.
[reaction: see text]. Three segment-coupling Prins approaches to the C3-C19 segment of phorboxazole B have been developed. One successful strategy utilized a novel TMSBr-mediated cyclization that proceeded with complete axial selectivity. Displacement of bromide with cesium acetate provided the C13 hydroxyl stereocenter of 22. Additionally, treatment of alpha-acetoxy ether 20 with TFA enabled a more concise synthesis of the C3-C19 target 13 by allowing direct access to the equatorial alcohol.
Vitale
Justin P
JP
Department of Chemistry, University of California--Irvine, 92697-2025, USA.
Wolckenhauer
Scott A
SA
Do
Nga M
NM
Rychnovsky
Scott D
SD
D000818:Animals; D003500:Cyclization; D006576:Heterocyclic Compounds, 4 or More Rings / Q000138:chemical synthesis* / Q000737:chemistry; D015394:Molecular Structure; D010080:Oxazoles / Q000138:chemical synthesis* / Q000737:chemistry; D011161:Porifera / Q000737:chemistry
D006576:Heterocyclic Compounds, 4 or More Rings; D010080:Oxazoles; C408887:phorboxazole A