Biomimetic synthesis of resorcylate natural products utilizing late stage aromatization: concise total syntheses of the marine antifungal agents 15G256iota and 15G256beta.
Diketo-1,3-dioxin-2-ones underwent retro-Diels-Alder reaction on heating in toluene at 110 degrees C to generate alpha,gamma,-triketo-ketenes. These were trapped with alcohols to provide 2,4,6-triketocarboxylates, which were smoothly aromatized by sequential reaction with potassium carbonate and methanolic hydrogen chloride to give resorcylate esters. The reaction was applied in the total synthesis of the marine antifungal agents 15G256beta (1), 15G256iota (2), and 15G256pi (3) and the mycotoxin S-(-)-zearalenone (4).
Navarro
Ismael
I
Department of Chemistry, Imperial College London, London SW7 2AZ, England.
Basset
Jean-François
JF
Hebbe
Séverine
S
Major
Sarah M
SM
Werner
Thomas
T
Howsham
Catherine
C
Bräckow
Jan
J
Barrett
Anthony G M
AG
D000935:Antifungal Agents / Q000138:chemical synthesis*; D001688:Biological Products / Q000138:chemical synthesis; D032701:Biomimetics / Q000379:methods*; D004147:Dioxins / Q000737:chemistry; D004952:Esters / Q000138:chemical synthesis; D007659:Ketones / Q000737:chemistry; D018942:Macrolides / Q000138:chemical synthesis*; D012118:Resorcinols / Q000138:chemical synthesis; D015025:Zearalenone / Q000138:chemical synthesis
C531522:15G256iota; D000935:Antifungal Agents; D001688:Biological Products; D004147:Dioxins; D004952:Esters; D007659:Ketones; D018942:Macrolides; D012118:Resorcinols; D015025:Zearalenone