Department of Chemical Science and Technology, Faculty of Engineering, The University of Tokushima, Minamijosanjimacho, Tokushima 770, Japan, and Department of Biochemistry, School of Medicine, The University of Tokushima, Kuramotocho, Tokushima 770, Japan. Received October 22, 1990 5, 6, 7-and 5, 7, &Trioxygenated 3', 4'-dihydroxyflavones were derivatized by introducing alkyl groups of various chain lengths at the 3-position of the ...