Structure Continued...

C₈H₁₁NO₃

Percent composition by mass of norepinephrine

56.8% C, 6.56% H, 28.4% O, 8.28%  N

Percent composition by number of norepinephrine

34.7% C, 47.8% H, 4.3% N, 13.0% O

All of the atoms are C, H, N, and O, so they would be covalently bonded. Also, as seen in the structure behind, there are some double bonds in the structural makeup. Catecholamines and structurally related compounds, including epinephrine, norepinephrine, dopamine, norephedrine, and tyramine, which normally bond in ways such as hyrophobic (away from water) , ionic and hydrogen-bonding interactions.

**Background picture is an example of hydrogen atoms filling in with catecholamines**