Sarcosine is a N-alkylglycine that is the N-methyl derivative of glycine. It is an intermediate in the metabolic pathway of glycine. It has a role as a glycine transporter 1 inhibitor, a glycine receptor agonist, a human metabolite, an Escherichia coli metabolite and a mouse metabolite. It is a N-alkylglycine, a N-methyl-amino acid and a member of N-methylglycines. It is a conjugate base of a sarcosinium. It is a conjugate acid of a sarcosinate. It is a tautomer of a sarcosine zwitterion.