Amino acid derivatives are compounds formed from amino acids, which are the building blocks of proteins. These derivatives can be created through various chemical modifications, such as methylation or hydroxylation, altering the original amino acid's structure and function. Some common examples include serotonin, derived from tryptophan, and dopamine, derived from tyrosine. These derivatives play crucial roles in biological processes. For instance, they can function as neurotransmitters, hormones, or precursors for other important biomolecules. Understanding amino acid derivatives is essential in fields like biochemistry and pharmacology, as they can influence health and disease states.