Concise total syntheses of aspalathin and nothofagin.
Syntheses of the C-glycosyl flavone natural products aspalathin and nothofagin have been accomplished in eight steps from tribenzyl glucal, tribenzylphloroglucinol, and either 4-(benzyloxy)phenylacetylene or 3,4-bis(benzyloxy)phenylacetylene. The key step of the syntheses involves a highly stereoselective Lewis acid promoted coupling of 1,2-di-O-acyl-3,4,6-tribenzylglucose with tribenzylphloroglucinol, which gives rise to the corresponding beta-C-aryl glycoside in 30-65% yields.
Yepremyan
Akop
A
Department of Chemistry and Biochemistry, California State University, Northridge, 18111 Nordhoff Street, Northridge, California 91330, USA.
Salehani
Baback
B
Minehan
Thomas G
TG
D001688:Biological Products / Q000138:chemical synthesis / Q000737:chemistry; D047188:Chalcones / Q000138:chemical synthesis* / Q000737:chemistry; D015394:Molecular Structure; D013237:Stereoisomerism
D001688:Biological Products; D047188:Chalcones; C517016:aspalathin; C528728:nothofagin