Melatonin

Melatonin is an indole-derived small molecule, N-acetyl-5-methoxytryptamine, examined in MT1 and MT2 receptor research.

Identity

Molecular formula

C₁₃H₁₆N₂O₂

Average molecular weight

232.28 g/mol

Monoisotopic mass (calculated)

232.1212 Da

CAS number

73-31-4

PubChem CID

896

Other names

N-Acetyl-5-methoxytryptamine

The data describe neutral melatonin. PubChem lists 8041-44-9 as another registry synonym; 73-31-4 is retained as its leading CAS identifier. Peptide sequence and UniProt do not apply; an intact SMILES string was not verified.

Identity data from: PubChem CID 896

Research overview

Melatonin is the indole-derived molecule N-acetyl-5-methoxytryptamine. Its molecular identity is separate from the identities of related ligands used to examine melatonin receptors. A receptor-focused review describes MT1 and MT2 as the best-characterized mammalian subtypes within the G protein-coupled receptor family. It discusses their preferential association with Gi/o proteins and notes that other G-protein associations depend on the cellular context. The review also distinguishes receptor structures, molecular simulations and intracellular signaling experiments as different approaches to understanding these systems. Such distinctions help keep a receptor-level description tied to the experimental method that produced it [1].

A structural study used cryo-electron microscopy to examine MT1–Gi and MT2–Gi signaling complexes with related receptor ligands, including 2-iodomelatonin. It combined structural observations with functional measurements to compare the receptors. The authors described broadly similar ligand-binding pockets together with subtype-specific features and differences in the arrangement of the receptor–G-protein complex. Those structures are models of the particular ligand-bound complexes analyzed, rather than direct images of every state of melatonin itself. The cited work therefore places Melatonin within receptor pharmacology and structural biology, while keeping ligand identity, receptor subtype and cellular conditions explicit. A receptor diagram and a small-molecule skeletal diagram describe different objects [2].

Laboratory storage and handling

Keep the sealed vial cold, dry and protected from light, following the conditions in the documentation supplied with the lot. Let the vial reach room temperature before opening to limit moisture condensation. Avoid repeated freezing and thawing of laboratory stocks. Record the lot identifier and the material form with each experiment, and use standard laboratory protective equipment.

Questions about Melatonin

References

1. Melatonin receptor structure and signaling. J Pineal Res 2024. PMID 38587234
2. Structural basis of the ligand binding and signaling mechanism of melatonin receptors. Nat Commun 2022. PMID 35075127

Identity data checked on 2026-10-03. Literature summaries describe published research models and are not specifications of any product lot.