using an cphi-4a spectrophotometer ( ussr ) , denaturation of dna containing approximately 2 % residual protein has been studied in the presence of catecholamines and their precursors : epinephrine , beta-3,4-dioxyphenylalanine , norepinephrine , 3,4-dimethoxyphenylethylamine , tyrosine , and phenylalanine .
C0014563
epinephrine
C0028351
norepinephrine