Synthesis of hydroxylated and prenylated chalcones

Abstract

Prenylated chalcones are among the compounds found in local Artocarpus species which reported to have interesting biological activities. Moreover, prenylated chalcones are used as traditional folk medicine for the treatment of inflammation, malarial fever and to treat the ulcers and diarrhea. In this study, 2,4-dihydroxy-3-C-prenylacetophenone and 2,4-dihydroxy-5-C-prenylacetophenone were successfully synthesized by treating resacetophenone with 2-methylbut-3-en-2-ol in the presence of BF3.Et2O as the catalyst. Meanwhile 2,4,6-trihydroxy-3-C-prenylacetophenone was synthesized using K2CO3 as the catalyst in dry acetone in the reaction of prenyl bromide with 2,4,6-trihydroxyacetophenone . In addition, two hydroxylated chalcone namely 2',4',4-trihydroxychalcone , 4',4-dihydroxychalcone) together with 2',4',4,6'-tetrahydroxy-3'-prenylchalcone were synthesized by Claisen-Schmidt condensation of various hydroxyacetophenone and 2,4,6-trihydroxy-3-C-prenylacetophenone for prenylated chalcone with 4-hydroxybenzaldyhe using BF3.Et2O. The structures of all compounds were characterized using spectroscopic methods (NMR and IR).