73-31-4Relevant articles and documents
Selective hydroformylation of N-allylacetamide in an inverted aqueous two-phase catalytic system, enabling a short synthesis of melatonin
Verspui, Goeran,Elbertse, Guido,Sheldon, Frank A.,Hacking, Michiel A. P. J.,Sheldon, Roger A.
, p. 1363 - 1364 (2000)
Water increases the selectivity in the Rh-phosphine catalysed hydroformylation of N-allylacetamide; an aqueous-organic biphasic system, containing a hydrophobic Rh-catalyst, provided facile catalyst/product separation, after which the aqueous product phase could be used in a one-pot synthesis of N-acetyl-5-methoxytryptamine (melatonin).
Significantly improved catalytic efficiency of caffeic acid O-methyltransferase towards N-acetylserotonin by strengthening its interactions with the unnatural substrate's terminal structure
Wang, Wenya,Su, Sisi,Wang, Shizhuo,Ye, Lidan,Yu, Hongwei
, p. 1 - 5 (2019)
O-Methylation of N-acetylserotonin (NAS) has been identified as the bottleneck in melatonin biosynthesis pathway. In the present paper, caffeic acid O-methyltransferase from Arabidopsis thaliana (AtCOMT) was engineered by rational design to improve its catalytic efficiency in conversion of NAS to melatonin. Based on the notable difference in the terminal structure of caffeic acid and NAS, mutants were designed to strengthen the interactions between the substrate binding pocket of the enzyme and the terminal structure of the unnatural substrate NAS. The final triple mutant (C296F-Q310L-V314T) showed 9.5-fold activity improvement in O-methylation of NAS. Molecular dynamics simulations and binding free energy analysis attributed the increased activity to the higher affinity between the substrate terminal structure and AtCOMT, resulting from the introduction of N–H?π interaction by Phe296 substitution, hydrophobic interaction by Thr314 substitution and elimination of electrostatic repulsion by substitution of Gln310 with Leu310. This work provides hints for O-methyltransferase engineering and meanwhile lays foundation for biotechnological production of melatonin.
Mechanisms of NO release by N1-nitrosomelatonin: Nucleophilic attack versus reducing pathways
De Biase, Pablo M.,Turjanski, Adrian G.,Estrin, Dario A.,Doctorovich, Fabio
, p. 5790 - 5798 (2005)
A new type of physiologically relevant nitrosamines have been recently recognized, the N1-nitrosoindoles. The possible pathways by which N1-nitrosomelatonin (NOMel) can react in physiological environments have been studied. Our results show that NOMel slowly decomposes spontaneously in aqueous solution, generating melatonin as the main organic product (k = (3.7 ± 1.1) × 10-5 s-1, Tris-HCl (0.2 M) buffer, pH 7.4 at 37°C, anaerobic). This rate is accelerated by acidification (kpH 5.8 = (4.5 ± 0.7) × 10-4 s-1, kpH 8.8 = (3.9 ± 0.6) × 10-6 s-1 Tris-HCl (0.2 M) buffer at 37°C), by the presence of O2 (k o = (9.8 ± 0.1) × 10-5 s-1 pH 7.4, 37°C, [NOMel] = 0.1 mM, P(O2) = 1 atm), and by the presence of the spin trap TEMPO (2,2,6,6-tetramethylpiperidine 1-oxyl; ko = (2.0 ± 0.1) × 10-4 s-1, pH 7.4, 37°C, [NOMel] = 0.1 mM, [TEMPO] = 9 mM). We also found that NOMel can transnitrosate to L-cysteinate, producing S-nitrosocysteine and melatonin (k = 0.127 ± 0.002 M-1 s-1, Tris-HCl (0.2 M) buffer, pH 7.4 at 37°C). The reaction of NOMel with ascorbic acid as a reducing agent has also been studied. This rapid reaction produces nitric oxide and melatonin. The saturation of the observed rate constant (k = (1.08 ± 0.04) × 10-3 s-1, Tris-HCl (0.2 M) buffer, pH 7.4 at 37°C) at high ascorbic acid concentration (100-fold with respect to NOMel) and the pH independence of this reaction in the pH range 7-9 indicate that the reactive species are ascorbate and melatonyl radical originated from the reversible homolysis of NOMel. Taking into account kinetic and DFT calculation data, a comprehensive mechanism for the denitrosation of NOMel is proposed. On the basis of our kinetics results, we conclude that under physiological conditions NOMel mainly reacts with endogenous reducing agents (such as ascorbic acid), producing nitric oxide and melatonin.
Preparations of 1-hydroxyindole derivatives and their potent inhibitory activities on platelet aggregation
Somei, Masanori,Yamada, Koji,Hasegawa, Masakazu,Tabata, Mutsuko,Nagahama, Yoshiyuki,Morikawa, Harunobu,Yamada, Fumio
, p. 1855 - 1858 (1996)
1-Hydroxymelatonin, 5-bromo- and 5,7-dibromo-1-hydroxytryptamine derivatives, 1,4-dihydroxy-5-nitroindole, 1-hydroxy-3-methylsulfinylmethylindole, and 5-acetyl-1,3,4,5-tetrahydro-1-hydroxypyrrolo[4,3,2-de]quinoline were synthesized for the first time. 1-Hydroxyindoles revealed potent inhibitory activities on platelet aggregation.
A practical synthesis of N-acetyl-5-methoxy-tryptamine (melatonin)
Hwang, Ki-Jun,Lee, Tae-Suk
, p. 2099 - 2104 (1999)
The pineal hormone melatonin is conveniently prepared in simple one pot operation by treating 4-methoxyphenylhydrazine hydrochloride(6) with acetic anhydride and 4-aminobutyraldehyde dimethylacetal(4) in a mixed solvent system of acetic acid/ethanol/water.
Melatonin- And Ferulic Acid-Based HDAC6 Selective Inhibitors Exhibit Pronounced Immunomodulatory Effects in Vitro and Neuroprotective Effects in a Pharmacological Alzheimer's Disease Mouse Model
He, Feng,Chou, C. James,Scheiner, Matthias,Poeta, Eleonora,Yuan Chen, Natalia,Gunesch, Sandra,Hoffmann, Matthias,Sotriffer, Christoph,Monti, Barbara,Maurice, Tangui,Decker, Michael
, p. 3794 - 3812 (2021)
The structures of melatonin and ferulic acid were merged into tertiary amide-based histone deacetylase 6 (HDAC6) inhibitors to develop multi-target-directed inhibitors for neurodegenerative diseases to incorporate antioxidant effects without losing affinity and selectivity at HDAC6. Structure-activity relationships led to compound 10b as a hybrid molecule showing pronounced and selective inhibition of HDAC6 (IC50 = 30.7 nM, > 25-fold selectivity over other subtypes). This compound shows comparable DPPH radical scavenging ability to ferulic acid, comparable ORAC value to melatonin and comparable Cu2+ chelating ability to EDTA. It also lacks neurotoxicity on HT-22 cells, exhibits a pronounced immunomodulatory effect, and is active in vivo showing significantly higher efficacy in an AD mouse model to prevent both Aβ25-35-induced spatial working and long-term memory dysfunction at lower dose (0.3 mg/kg) compared to positive control HDAC6 inhibitor ACY1215 and an equimolar mixture of the three entities ACY1215, melatonin and ferulic acid, suggesting potentially disease-modifying properties.
A facile and versatile electro-reductive system for hydrodefunctionalization under ambient conditions
Huang, Binbin,Guo, Lin,Xia, Wujiong
supporting information, p. 2095 - 2103 (2021/03/26)
A general electrochemical system for reductive hydrodefunctionalization is described, employing the inexpensive and easily available triethylamine (Et3N) as a sacrificial reductant. This protocol is characterized by facile operation, sustainable conditions, and exceptionally wide substrate scope covering the cleavage of C-halogen, N-S, N-C, O-S, O-C, C-C and C-N bonds. Notably, the selectivity and capability of reduction can be conveniently switched by simple incorporation or removal of an alcohol as a co-solvent.
Recyclable and reusablen-Bu4NBF4/PEG-400/H2O system for electrochemical C-3 formylation of indoles with Me3N as a carbonyl source
Cheng, Didi,Li, Jingyi,Li, Yujin,Ling, Fei,Liu, Lei,Liu, Tao,Zhong, Weihui
supporting information, p. 4107 - 4113 (2021/06/17)
A safe, practical and eco-friendly electrochemical methodology for the synthesis of 3-formylated indoles has been developed by the utilization of Me3N as a novel formylating reagent. Stoichiometric oxidants, metal catalysts, and activating agents were avoided in this method, and an aqueous biphasic system ofn-Bu4NBF4/PEG-400/H2O was used as a recyclable and reusable reaction medium, which made this electrosynthesis approach more sustainable and environmentally friendly. This process expanded the substrate scope and functional group tolerance for bothN-EDG andN-EWG indoles. Furthermore, late-stage functionalization and total/formal synthesis of drugs and natural products were realized by means of this route.
Synthesis method of melatonin
-
Paragraph 0020-0025, (2021/08/07)
The invention discloses a synthesis method of melatonin, and belongs to the technical field of pharmaceutical chemistry synthesis. According to the method, 5-hydroxytryptamine hydrochloride is used as a raw material, 5-methoxytryptamine is obtained through a methylation reaction of hydroxyl through a one-pot feeding method, a crude melatonin product is prepared through an acetylation reaction of amino, and finally, the finished melatonin is obtained through one-step refining and purification. The melatonin synthesis method provided by the invention avoids waste caused by step-by-step purification of the product, and has the characteristics of short synthesis route, short synthesis period, few raw material types and the like, the obtained product is high in yield, and the purity can meet the market demand. The synthesis method of the melatonin provided by the invention saves the cost and is easy for industrial production.
Discovery and characterization of an acridine radical photoreductant
MacKenzie, Ian A.,Wang, Leifeng,Onuska, Nicholas P. R.,Williams, Olivia F.,Begam, Khadiza,Moran, Andrew M.,Dunietz, Barry D.,Nicewicz, David A.
, p. 76 - 80 (2020/04/17)
Photoinduced electron transfer (PET) is a phenomenon whereby the absorption of light by a chemical species provides an energetic driving force for an electron-transfer reaction1–4. This mechanism is relevant in many areas of chemistry, including the study of natural and artificial photosynthesis, photovoltaics and photosensitive materials. In recent years, research in the area of photoredox catalysis has enabled the use of PET for the catalytic generation of both neutral and charged organic free-radical species. These technologies have enabled previously inaccessible chemical transformations and have been widely used in both academic and industrial settings. Such reactions are often catalysed by visible-light-absorbing organic molecules or transition-metal complexes of ruthenium, iridium, chromium or copper5,6. Although various closed-shell organic molecules have been shown to behave as competent electron-transfer catalysts in photoredox reactions, there are only limited reports of PET reactions involving neutral organic radicals as excited-state donors or acceptors. This is unsurprising because the lifetimes of doublet excited states of neutral organic radicals are typically several orders of magnitude shorter than the singlet lifetimes of known transition-metal photoredox catalysts7–11. Here we document the discovery, characterization and reactivity of a neutral acridine radical with a maximum excited-state oxidation potential of ?3.36 volts versus a saturated calomel electrode, which is similarly reducing to elemental lithium, making this radical one of the most potent chemical reductants reported12. Spectroscopic, computational and chemical studies indicate that the formation of a twisted intramolecular charge-transfer species enables the population of higher-energy doublet excited states, leading to the observed potent photoreducing behaviour. We demonstrate that this catalytically generated PET catalyst facilitates several chemical reactions that typically require alkali metal reductants and can be used in other organic transformations that require dissolving metal reductants.
