RESUMEN
An enantioselective synthesis of the ABD-ring of (-)-phomactin A is described here. The sequence features Rawal's asymmetric Diels-Alder cycloaddition. The overall length is significantly reduced from our previous attempt.
RESUMEN
An enantioselective synthesis of the ABD-ring of (-)-phomactin A is described here. The sequence features Rawal's asymmetric Diels-Alder cycloaddition. The overall length is significantly reduced from our previous attempt.
RESUMEN
An unusual polyene cyclization pathway that led to a divergent total synthesis of hongoquercin A and rhododaurichromanic acid A is described here. This work uncovered a unique cationic cyclobutane formation that could be relevant to the biosynthetic pathway for the formation of cyclobutane containing terpenoids in addition to rhododaurichromanic acids.
Asunto(s)
Cromanos/síntesis química , Sesquiterpenos/síntesis química , Cationes/química , Ciclización , Ciclobutanos , PolienosRESUMEN
[reaction: see text] A Lewis acid-catalyzed formal cycloaddition of alpha,beta-unsaturated aldehydes with 6-methyl-4-hydroxy-2-pyrone, 1,3-diketones, and vinylogous silyl esters is described here.
Asunto(s)
Aldehídos/química , Cetonas/química , Piranos/síntesis química , Pironas/química , Compuestos de Vinilo/química , Catálisis , Ciclización , Ésteres , Indicadores y Reactivos , Estructura Molecular , Piranos/química , EstereoisomerismoRESUMEN
[reaction: see text] Total syntheses of (+/-)-rhododaurichromanic acids A and B and methyl (+/-)-daurichromenic ester are described here. Despite the complex appearances of these compounds, their syntheses are completed in six steps with a 15% overall yield as a mixture by featuring our formal oxa-[3 + 3] cycloaddition methodology.