539-15-1Relevant articles and documents
THE BIOSYNTHESIS OF SCELETIUM ALKALOIDS IN SCELETIUM SUBVELUTINUM
Herbert, Richard B.,Kattah, Abdullah E.
, p. 141 - 144 (1989)
Six Sceletium (Mesembrine) alkaloids (1)-(6) are identified, together with N,N-dimethyltyramine (10) as constituents of Sceletium subvelutinum.The alkaloids (1)-(6) incorporate label from radioactive tyramine (8) and 4-hydroxyphenylpropionic acid (12) as expected; notably -4-hydroxydihydrocinnamaldehyde is a more efficient alkaloid precursor than the acid (12).Preliminary evidence locates the amine (16) potentially as a key precursor for Sceletium alkaloids; (14) is less efficiently incorporated.
Metabolism of hordenine in Homogenates from Hordeum Vulgare Roots
Russo, Cesar A.,Burton, Gerardo,Gros, Eduardo G.
, p. 71 - 74 (1983)
Analysis by 13C NMR spectroscopy of the metabolic degradation of hordenine by root homogenates of Hordeum vulgare indicated a stepwise loss of the N-methyl groups, hordenine being converted in N-methyltyramine and probably tyramine.
STRUCTURE OF THE NEW DITERPENE ALKALOID ZERACONINE AND ITS N-OXIDE
Vaisov, Z. M.,Yunusov, M. S.
, p. 337 - 338 (1987)
The structures of the new diterpene alkaloid zeraconine and its N-oxide, isolated from Aconitum zeravschanicum, have been established on the basis of spectral characteristics and chemical transformations.
Preparation method of hordenine hydrochloride
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Paragraph 0042-0045, (2021/11/10)
The invention discloses a preparation method of hordenine hydrochloride. The preparation method comprises the following steps: taking 4-(2-bromoethyl)phenol as a raw material, adding ethanol to prepare a solution, dropwise adding excessive dimethylamine solution, and stirring at a lower temperature to carry out amination reaction to obtain hordenine hydrobromide. The proper excessive dimethylamine is adopted, so that the quaternization side reaction is effectively inhibited, the solvent dispersion effect is also played, the contact reaction opportunity of the hordenine product generated in the first reaction and the 4-(2-bromoethyl)phenol added later is greatly reduced, the high product yield can be kept, and meanwhile the low preparation cost is achieved; 4-(2-bromoethyl) phenol is added into ethanol to prepare a dilute solution of ethanol, and the dilute solution of ethanol is dropwise added into a dimethylamine solution to improve the dispersity of 4-(2-bromoethyl) phenol in a reaction system and inhibit quaternization side reaction; and the amination reaction is carried out by stirring at a relatively low temperature of 10-25 DEG C, so that the occurrence of quaternization side reaction is inhibited, and a relatively good reaction effect is achieved.
Simple RuCl3-catalyzed N-Methylation of Amines and Transfer Hydrogenation of Nitroarenes using Methanol
Sarki, Naina,Goyal, Vishakha,Tyagi, Nitin Kumar,Puttaswamy,Narani, Anand,Ray, Anjan,Natte, Kishore
, p. 1722 - 1729 (2021/04/19)
Methanol is a potential hydrogen source and C1 synthon, which finds interesting applications in both chemical synthesis and energy technologies. The effective utilization of this simple alcohol in organic synthesis is of central importance and attracts scientific interest. Herein, we report a clean and cost-competitive method with the use of methanol as both C1 synthon and H2 source for selective N-methylation of amines by employing relatively cheap RuCl3.xH2O as a ligand-free catalyst. This readily available catalyst tolerates various amines comprising electron-deficient and electron-donating groups and allows them to transform into corresponding N-methylated products in moderate to excellent yields. In addition, few marketed pharmaceutical agents (e. g., venlafaxine and imipramine) were also successfully synthesized via late-stage functionalization from readily available feedstock chemicals, highlighting synthetic value of this advanced N-methylation reaction. Using this platform, we also attempted tandem reactions with selected nitroarenes to convert them into corresponding N-methylated amines using MeOH under H2-free conditions including transfer hydrogenation of nitroarenes-to-anilines and prepared drug molecules (e. g., benzocaine and butamben) as well as key pharmaceutical intermediates. We further enable one-shot selective and green syntheses of 1-methylbenzimidazole using ortho-phenylenediamine (OPDA) and methanol as coupling partners.
Catalytic Strategy for Regioselective Arylethylamine Synthesis
Boyington, Allyson J.,Seath, Ciaran P.,Zearfoss, Avery M.,Xu, Zihao,Jui, Nathan T.
supporting information, p. 4147 - 4153 (2019/03/07)
A mild, modular, and practical catalytic system for the synthesis of the highly privileged phenethylamine pharmacophore is reported. Using a unique combination of organic catalysts to promote the transfer of electrons and hydrogen atoms, this system performs direct hydroarylation of vinyl amine derivatives with a wide range of aryl halides (including aryl chlorides). This general and highly chemoselective protocol delivers a broad range of arylethylamine products with complete regiocontrol. The utility of this process is highlighted by its scalability and the modular synthesis of an array of bioactive small molecules.
Commercial Pd/C-Catalyzed N-Methylation of Nitroarenes and Amines Using Methanol as Both C1 and H2 Source
Goyal, Vishakha,Gahtori, Jyoti,Narani, Anand,Gupta, Piyush,Bordoloi, Ankur,Natte, Kishore
, p. 15389 - 15398 (2019/12/04)
Herein, we report commercially available carbon-supported-palladium (Pd/C)-catalyzed N-methylation of nitroarenes and amines using MeOH as both a C1 and a H2 source. This transformation proceeds with high atom-economy and in an environmentally friendly way via borrowing hydrogen mechanism. A total of >30 structurally diverse N-methylamines, including bioactive compounds, were selectively synthesized with isolated yields of up to 95%. Furthermore, selective N-methylation and deuteration of nimesulide, a nonsteroidal anti-inflammatory drug, were realized through the late-stage functionalization.
Desvenlafaxine succinate impurities as well as preparation method and use thereof
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Paragraph 0045, (2018/06/15)
The invention discloses desvenlafaxine succinate impurities, i.e., desvenlafaxine succinate impurity 2 and desvenlafaxine succinate impurity I. In addition, the invention further discloses a preparation method of a desvenlafaxine succinate impurity 2, a desvenlafaxine succinate impurity 5, a desvenlafaxine succinate impurity 6, a desvenlafaxine succinate impurity 7, a desvenlafaxine succinate impurity H and a desvenlafaxine succinate impurity I. According to the desvenlafaxine succinate related impurities and preparation thereof, provided by the invention, a foundation for quality research onintermediates, raw pharmaceutical materials and compositions of desvenlafaxine succinate is laid.
Selective Monomethylation of Amines with Methanol as the C1 Source
Choi, Geunho,Hong, Soon Hyeok
supporting information, p. 6166 - 6170 (2018/04/30)
The N-monomethyl functionality is a common motif in a variety of synthetic and natural compounds. However, facile access to such compounds remains a fundamental challenge in organic synthesis owing to selectivity issues caused by overmethylation. To address this issue, we have developed a method for the selective, catalytic monomethylation of various structurally and functionally diverse amines, including typically problematic primary aliphatic amines, using methanol as the methylating agent, which is a sustainable chemical feedstock. Kinetic control of the aliphatic amine monomethylation was achieved by using a readily available ruthenium catalyst at an adequate temperature under hydrogen pressure. Various substrates including bio-related molecules and pharmaceuticals were selectively monomethylated, demonstrating the general utility of the developed method.
A short and efficient total synthesis of the bromotyrosine-derived alkaloid psammaplysene A
Xu, Jingjing,Wang, Kai,Wu, Jinlong
, p. 13747 - 13749 (2018/04/25)
Psammaplysene A, an inhibitor of FOXO1a-mediated nuclear export, has been synthesized by a concise and improved route from tyrosine-derived acid and amine fragments which were easily constructed using commercially available p-hydroxybenzaldehyde and tyramine as starting material, respectively. The strategy provides an efficient access of psammaplysene analogues that can be explored for potential pharmaceutical or biological activities.
