Tyrosine can be a non-essential phenylalanine-derived amino acid. Tyrosine’s construction is produced a para-hydroxylated phenyl ring linked to a pentanoic acid team, that's a 5 member carbon chain with a carboxyl (C(=O)OH) team to the terminal carbon. This pentanoic acid chain is substituted at R2 with an amino group in https://revivalschem.com/product/buy-blue-mandala-mix/