Tyrosine is actually a non-crucial phenylalanine-derived amino acid. Tyrosine’s framework is made a para-hydroxylated phenyl ring connected to a pentanoic acid team, that's a 5 member carbon chain which has a carboxyl (C(=O)OH) group to the terminal carbon. This pentanoic acid chain is substituted at R2 with the amino group https://revivalschem.com/product/buy-1b-lsd-125-mcg-blotters/