N,N-dimethyl-3-methoxytyramine + S-adenosyl-L-homocysteine + H(+) => N-methyl-3-methoxytyramine + S-adenosyl-L-methionine
n,n-dimethyl-3-methoxytyramine + s-adenosyl-l-homocysteine + h(+) => n-methyl-3-methoxytyramine + s-adenosyl-l-methionine