3,7-dimethylquercitin 4'-O-methyltransferase activity
3,7-dimethylquercitin 4'-o-methyltransferase activity
Catalysis of the reaction: 3',4',5-trihydroxy-3,7-dimethoxyflavone + S-adenosyl-L-methionine(1+) = 3',5-dihydroxy-3,4',7-trimethoxyflavone + S-adenosyl-L-homocysteine + H+.