A convenient synthesis of prenylated isoflavones : Synthesis of licoricone and related compounds.

Phenolic Constituents of Licorice (Glycyrrhiza Species)

“…11 0-140 analysis of its monobromoacetate (270). Syntheses of licoricone and related compounds have been carried out by TSUKAYAMA et al (271). Formula 163 originally attributed to licoricidin on the basis of the IH NMR spectrum and the shift of an aromatic proton which accompanied acetylation (267) was revised to 164 using 13C NMR spectrometry (272).…”

“…LITVINENKO and NADEZHINA isolated the cis-3-hydroxyflavanone folerogenin (269) from the species (342,343). Three new glucosides, glyphoside (270), kaempferol-3-0-diglucoside (271) and astragalin (kaempferol-3-0-glucoside) monoacetate (272), have been isolated, but the structure of the glycosyl moiety of 271 and the position of the acetate of 272 have not been elucidated (342,344).…”

The First Total Synthesis of (±)-Linderol A, a Tricyclic Hexahydrodibenzofuran Constituent of Lindera umbellata Bark, with Potent Inhibitory Activity on Melanin Biosynthesis of Cultured B-16 Melanoma Cells

“…The starting material, 4,6-dimethoxysalicylaldehyde 4 , was converted to the coumarin 5 by Knoevenagel reaction in 97.0% yield, and the product 5 was treated with 2.2 equiv of dimethylsulfoxonium methylide according to the previously reported procedure 3 to afford the rearranged cyclopenta[ b ]benzofuran derivative 6 in 78.8% yield . The benzofuran 6 was converted to the α,β-unsaturated ketoester 7 according to the well-known phenylselenenylation−oxidation methodology .…”