Which is not a biological derivative of tyrosine?

Uses of tyrosine: =Melatonin is formed from tryptophan not from tyrosine Tip to remember:- Tyrosine (smaller name) - Melanin (smaller name) Tryptophan (bigger name) - Melatonin (bigger name) Extra information:- Phenylalanine is conveed to tyrosine by enzyme Phenylalanine Hydroxylase. Therefore tyrosine is non-essential as it can be synthesized in body from phenylalanine. Other uses of tryptophan are- Synthesis of vitamin B3 and serotonin