4-hydroxy-3,5-dimethoxyphenethylamine + S-adenosyl-L-methionine = mescaline + S-adenosyl-L-homocysteine + H(+)
4-hydroxy-3,5-dimethoxyphenethylamine + s-adenosyl-l-methionine = mescaline + s-adenosyl-l-homocysteine + h(+)