Abstract
For the purpose of preparing 7-flavonylmethyl carbamate derivatives, syntheses of a series of 7-substituted flavones were attempted by use of 7-hydroxyflavone as a starting material.
The following 7-substituted flavones have been prepared, namely, 7-haloflavones, 7-cyanoflavone, flavone-7-carboxylic acid and related derivatives, 7-hydroxymethyl-flavone, and 7-flavonylmethyl carbamate derivatives.
In the case of the synthesis of 7-hydroxymethylflavone, the reduction of the ester group in flavone derivatives was studied and it was found that ethyl-7-flavonoxyacetate was converted into 7- (hydroxyethoxy) -flavone in good yield at low temperature with lithiumaluminum hydride.
Some β (7-flavonoxy) ethyl carbamate derivatives have also been prepared.
