Methylation of mangiferin: in a solution of mangiferin, acetone was reacted with dimethyl sulphate and K 2 CO 3 at 25 °C for one week, the reaction mixture was further concentrated with the help of a rotary evaporator that provided a residue that was subjected to purification with column chromatography using chloroform:methanol as eluent to provide the desired compound, methyl mangiferin (4).