{"id":3912,"date":"2025-09-06T10:08:58","date_gmt":"2025-09-06T10:08:58","guid":{"rendered":"https:\/\/modafinil.pl\/?post_type=product&p=3912"},"modified":"2026-10-03T06:04:23","modified_gmt":"2026-10-03T06:04:23","slug":"melatonin","status":"publish","type":"product","link":"https:\/\/modafinil.pl\/en\/sklep\/melatonin\/","title":{"rendered":"Melatonin (CAS 73-31-4) \u2014 Chemical Reagent 1000 mg, Purity \u2265 98%"},"content":{"rendered":"

N-[2-(5-methoxy-1H-indol-3-yl)ethyl]acetamide<\/strong>, crystalline powder, 1000 mg package. Material intended exclusively for in vitro laboratory and analytical research<\/strong>. The product is not intended for consumption by humans or animals<\/strong>, and is not a medicinal product, dietary supplement, food, or cosmetic.<\/p>\n

Three Different Entities That Must Not Be Confused<\/h2>\n

For this molecule, separating the layers is especially important, because unlike most of our catalog, melatonin is an endogenous<\/strong> compound \u2014 produced naturally by the organism \u2014 while also being sold commercially under two entirely different legal regimes at once. Three contexts, three completely different statuses:<\/p>\n\n\n\n\n\n\n\n
Separating the layers: substance \u2014 supplement\/drug \u2014 reagent<\/caption>\n
Entity<\/th>\nWhat it is<\/th>\nWhat it concerns<\/th>\n<\/tr>\n<\/thead>\n
Chemical substance
melatonin, CAS 73-31-4<\/th>\n		A chemical concept \u2014 a molecule with a defined structure, produced endogenously by many living organisms. On its own it is neither a supplement, nor a drug, nor a reagent; its status is conferred by the form in which it has been manufactured, purified, and placed on the market.<\/td>\nchemistry, biochemistry, substance registries<\/td>\n<\/tr>\n
Dietary supplement \/ medicinal product
commercially available preparations<\/th>\n		In many countries, including Poland, melatonin is authorized for sale as a dietary supplement<\/strong> without a prescription. In the European Union, a controlled-release medicinal product<\/strong> has also been authorized, manufactured under pharmaceutical-grade regulation, with its own registration dossier and safety oversight. It is these forms \u2014 not the reagent \u2014 that human studies concern<\/strong>, including a clinical trial of a prolonged-release product in patients within a defined age range [17].<\/td>\nsupplementation, pharmacy, retail trade<\/td>\n<\/tr>\n
Chemical reagent
the material offered here<\/th>\n		Material for laboratory and analytical work. It does not have, and cannot have, authorization for use in humans or animals<\/strong> \u2014 it has no pharmaceutical form, is not manufactured or labeled as a dietary supplement, and is not accompanied by documentation appropriate to either of those products.<\/td>\nanalytics, chemistry, reference standards<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

The consequence is unambiguous.<\/strong> Information on effects circulating publicly concerns the dietary supplement or the registered medicinal product<\/strong> \u2014 never the analytical reagent offered here. The basic research cited further on this page concerns the chemistry and biosynthesis of the molecule<\/strong>, carried out on model organisms (laboratory animals, plants, yeast) under experimental conditions \u2014 not on the material in the form sold here, and it does not carry over to its use.<\/p>\n

Reagent Identification Card<\/h2>\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n
Registry data and identifiers \u2014 melatonin<\/caption>\n
Systematic name (IUPAC)<\/th>\nN-[2-(5-methoxy-1H-indol-3-yl)ethyl]acetamide<\/td>\n<\/tr>\n
Common name<\/th>\nmelatonin<\/td>\n<\/tr>\n
CAS number<\/th>\n73-31-4<\/td>\n<\/tr>\n
Molecular formula<\/th>\nC13<\/sub>H16<\/sub>N2<\/sub>O2<\/sub><\/td>\n<\/tr>\n
Molar mass<\/th>\n232.28 g\u00b7mol\u22121<\/sup><\/td>\n<\/tr>\n
Monoisotopic mass<\/th>\n232.1212 Da<\/td>\n<\/tr>\n
InChIKey<\/th>\nDRLFMBDRBRZALE-UHFFFAOYSA-N<\/td>\n<\/tr>\n
SMILES<\/th>\nCC(=O)NCCC1=CNC2=C1C=C(C=C2)OC<\/td>\n<\/tr>\n
PubChem CID<\/th>\n896<\/a><\/td>\n<\/tr>\n
UNII (FDA)<\/th>\nJL5DK93RCL<\/td>\n<\/tr>\n
ChEMBL<\/th>\nCHEMBL3942629<\/a><\/td>\n<\/tr>\n
Melting point<\/th>\n117\u00b0C (NIST)<\/td>\n<\/tr>\n
Form<\/th>\ncrystalline powder, white to slightly yellowish<\/td>\n<\/tr>\n
Purity<\/th>\n\u2265 98% (HPLC)<\/td>\n<\/tr>\n
Intended use<\/th>\nresearch reagent \u2014 not for consumption by humans or animals<\/strong><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

Lineage of the Molecule: an Indole Hormone Found Throughout the Tree of Life<\/h2>\n

Unlike the synthetic molecules in our catalog, melatonin is an endogenous<\/strong> compound \u2014 its lineage is not the history of a single laboratory and a single synthetic route, but the history of a biochemical pathway present in parallel in animals, plants, fungi, and some microorganisms. This makes it an atypical item: it was not “invented” in the chemical sense, but rather isolated and identified<\/strong> as a pre-existing product of metabolism.<\/p>\n

Discovery and Isolation<\/h3>\n

The substance was isolated and identified from the bovine pineal gland in 1958<\/strong> \u2014 this date can be reconstructed directly from the title of a later review, published exactly fifty years afterward and referring to this discovery [1]. The next milestone was the elucidation of its formation outside the pineal gland: melatonin was also identified in the gastrointestinal tract, as documented in a 2008 review referring to a discovery made thirty-four years earlier [2].<\/p>\n

The Enzymatic Biosynthesis Pathway<\/h3>\n

The pathway of melatonin formation was elucidated in two stages of research spanning the 1950s to the 1970s. In 1960, the enzymatic O-methylation of N-acetylserotonin to melatonin<\/strong> was described \u2014 the final step of the serotonin \u2192 N-acetylserotonin \u2192 melatonin pathway [3]. In 1971, the neural regulation of the enzyme responsible for an earlier step of this pathway, serotonin acetyltransferase, was characterized [4]. The same pathway, at the chemical level, was later also described in gastrointestinal tissue \u2014 using an HPLC method allowing the simultaneous separation of six tryptophan metabolites along the route to melatonin [5].<\/p>\n

Beyond Vertebrates: Plants, Yeast, Bacteria<\/h3>\n

The same enzymatic pathway \u2014 with local variations \u2014 functions in organisms that are not phylogenetically related to animals. Genome-wide analysis of serotonin and melatonin biosynthesis genes in plants showed their conserved role in stress response and development [6]. In the yeast Saccharomyces cerevisiae<\/em>, the PAA1 gene was identified as a candidate for a new arylalkylamine N-acetyltransferase involved in this pathway [7]. This fact also has a practical application: in 2024, the metabolic engineering of an Escherichia coli<\/em> strain was described, constructed to synthesize melatonin from L-tryptophan in submerged culture \u2014 a proof-of-concept study, presented by its authors as a fast and economical synthesis strategy, potentially an alternative to purely chemical synthesis [8].<\/p>\n

Timeline<\/h2>\n\n\n\n\n\n\n\n\n\n\n\n\n
Timeline: identification and study of the molecule<\/caption>\n
1958<\/th>\nisolation and identification of the substance from the bovine pineal gland [1]<\/td>\n<\/tr>\n
1960<\/th>\ndescription of the enzymatic biosynthesis step \u2014 O-methylation of N-acetylserotonin [3]<\/td>\n<\/tr>\n
1971<\/th>\ncharacterization of the neural regulation of serotonin acetyltransferase [4]<\/td>\n<\/tr>\n
1974<\/th>\nidentification of melatonin outside the pineal gland, in the gastrointestinal tract [2]<\/td>\n<\/tr>\n
1988<\/th>\ndocumented methodological difficulties of GC-MS determination with SPE extraction [9]<\/td>\n<\/tr>\n
2004<\/th>\nsensitive HPLC method with precolumn oxidation for determinations in mammalian tissues [10]<\/td>\n<\/tr>\n
2006<\/th>\nimproved photostability through encapsulation in lipospheres [11]<\/td>\n<\/tr>\n
2020\u20132023<\/th>\nextension of biosynthesis knowledge to plants and yeast [6][7]<\/td>\n<\/tr>\n
2024<\/th>\nmicrobial biosynthesis from L-tryptophan in an engineered bacterial cell [8]<\/td>\n<\/tr>\n
2026<\/th>\nstudies of melatonin coordination in magnesium porphyrins and its photostability [12]; review of analytical determination methods [16]<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

Chemistry: an Indole Ring Without a Stereogenic Center<\/h2>\n

Why Melatonin Has No Optical Isomers<\/h3>\n

This is a significant difference compared with other items in our catalog. In modafinil<\/a>, the stereogenic center lies on the sulfur atom, which necessitates the existence of a pair of enantiomers. Melatonin has no such center<\/strong> \u2014 its skeleton is a flat indole ring with an ethylamide side chain, without a carbon atom (or any other atom) bonded to four different substituents. The molecule is achiral. For the laboratory, this has a practical consequence: confirming identity and purity does not require an enantioselective method or a chiral column<\/strong> \u2014 unlike modafinil or its analogs.<\/p>\n

Physicochemical Characteristics<\/h3>\n\n\n\n\n\n\n\n\n\n\n\n
Computed descriptors and their analytical significance<\/caption>\n
Parameter<\/th>\nValue<\/th>\nWhat this means<\/th>\n<\/tr>\n<\/thead>\n
Partition coefficient (XLogP)<\/th>\n0.8<\/td>\nthe lowest lipophilicity among the benzhydryl\/adamantane molecules in our catalog \u2014 elutes early in RP-HPLC<\/td>\n<\/tr>\n
Topological polar surface area (TPSA)<\/th>\n54.1 \u00c52<\/sup><\/td>\nmoderate; presence of the indole NH and the amide group<\/td>\n<\/tr>\n
Hydrogen bond donors<\/th>\n2<\/td>\nthe NH of the indole ring and the NH of the amide group<\/td>\n<\/tr>\n
Hydrogen bond acceptors<\/th>\n2<\/td>\nthe methoxy oxygen and the carbonyl oxygen of the amide<\/td>\n<\/tr>\n
Rotatable bonds<\/th>\n4<\/td>\nflexible side chain \u2014 several conformers of similar energy<\/td>\n<\/tr>\n
Heavy atoms<\/th>\n17<\/td>\na small molecule by the analytical standard of this group<\/td>\n<\/tr>\n
Solubility<\/th>\ngood in DMSO, methanol, and ethanol; poor in water<\/td>\nprepare stock solutions in an organic solvent<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

Stability and Light Sensitivity<\/h3>\n

The indole ring makes melatonin susceptible to photochemical degradation and oxidation \u2014 which is why storage in the dark is a chemical requirement, not merely a precautionary recommendation. Encapsulation in lipid carriers was the subject of a study aimed at improving the molecule’s photostability [11], and the most recent work in inorganic chemistry analyzes the excited-state dynamics and photostability of melatonin coordinated in magnesium porphyrins [12]. The material in solid form, protected from light and moisture, is considerably more stable than in solution.<\/p>\n

Nomenclature and Synonyms<\/h2>\n