抄録
Isomerization of a chalcone having several benzyloxyl groups into a flavanone by the use of phosphoric acid in methyl cellosolve was investigated, and higher yields of flavanones were obtained with much shorter reaction times than in the conventional procedure. The reaction was applied to the synthesis of three flavanones, agestricins B, C and D, isolated from Ageratum strictum. A chalcone, agestricin A, was also prepared to confirm its structure.
