- THE BIOSYNTHESIS OF SCELETIUM ALKALOIDS IN SCELETIUM SUBVELUTINUM
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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.
- Herbert, Richard B.,Kattah, Abdullah E.
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- Metabolism of hordenine in Homogenates from Hordeum Vulgare Roots
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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.
- Russo, Cesar A.,Burton, Gerardo,Gros, Eduardo G.
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- STRUCTURE OF THE NEW DITERPENE ALKALOID ZERACONINE AND ITS N-OXIDE
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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.
- Vaisov, Z. M.,Yunusov, M. S.
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- Preparation method of hordenine hydrochloride
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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.
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Paragraph 0042-0045
(2021/11/10)
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- Simple RuCl3-catalyzed N-Methylation of Amines and Transfer Hydrogenation of Nitroarenes using Methanol
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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.
- Sarki, Naina,Goyal, Vishakha,Tyagi, Nitin Kumar,Puttaswamy,Narani, Anand,Ray, Anjan,Natte, Kishore
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p. 1722 - 1729
(2021/04/19)
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- Commercial Pd/C-Catalyzed N-Methylation of Nitroarenes and Amines Using Methanol as Both C1 and H2 Source
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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.
- Goyal, Vishakha,Gahtori, Jyoti,Narani, Anand,Gupta, Piyush,Bordoloi, Ankur,Natte, Kishore
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p. 15389 - 15398
(2019/12/04)
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- Catalytic Strategy for Regioselective Arylethylamine Synthesis
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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.
- Boyington, Allyson J.,Seath, Ciaran P.,Zearfoss, Avery M.,Xu, Zihao,Jui, Nathan T.
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supporting information
p. 4147 - 4153
(2019/03/07)
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- A short and efficient total synthesis of the bromotyrosine-derived alkaloid psammaplysene A
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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.
- Xu, Jingjing,Wang, Kai,Wu, Jinlong
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p. 13747 - 13749
(2018/04/25)
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- Desvenlafaxine succinate impurities as well as preparation method and use thereof
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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.
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Paragraph 0045
(2018/06/15)
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- Selective Monomethylation of Amines with Methanol as the C1 Source
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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.
- Choi, Geunho,Hong, Soon Hyeok
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supporting information
p. 6166 - 6170
(2018/04/30)
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- Synthetic analogs of stryphnusin isolated from the marine sponge: Stryphnus fortis inhibit acetylcholinesterase with no effect on muscle function or neuromuscular transmission
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The marine secondary metabolite stryphnusin (1) was isolated from the boreal sponge Stryphnus fortis, collected off the Norwegian coast. Given its resemblance to other natural acetylcholinesterase antagonists, it was evaluated against electric eel acetylcholinesterase and displayed inhibitory activity. A library of twelve synthetic phenethylamine analogs, 2a-7a and 2b-7b, containing tertiary and quaternary amines respectively were synthesized to investigate the individual structural contributions to the activity. Compound 7b was the strongest competitive inhibitor of both acetylcholinesterase and butyrylcholinesterase with IC50 values of 57 and 20 μM, respectively. This inhibitory activity is one order of magnitude higher than the positive control physostigmine, and is comparable with several other marine acetylcholinesterase inhibitors. The physiological effect of compound 7b on muscle function and neuromuscular transmission was studied and revealed a selective mode of action at the investigated concentration. This data is of importance as the interference of therapeutic acetylcholinesterase inhibitors with neuromuscular transmission can be problematic and lead to unwanted side effects. The current findings also provide additional insights into the structure-activity relationship of both natural and synthetic acetylcholinesterase inhibitors.
- Moodie, Lindon W. K.,?u?ek, Monika C.,Frange?, Robert,Andersen, Jeanette H.,Hansen, Espen,Olsen, Elisabeth K.,Cergolj, Marija,Sep?i?, Kristina,Hansen, Kine ?.,Svenson, Johan
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p. 11220 - 11229
(2016/12/07)
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- SIGMA-1 RECEPTOR LIGANDS AND METHODS OF USE
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The invention provides compounds of formula I and compositions thereof. The invention further provides methods of using the compounds and compositions. The compounds of the invention can provide high affinity binding to sigma-1 receptors in a mammal. The compounds can exhibit selectivity for the sigma-1 receptor over the sigma-2 receptor. The compounds and compositions of the invention can also be used to treat conditions that involve the sigma-1 receptor, such as addiction, cardiovascular conditions, and cancer, for example, cancer of the breast, lung, prostate, ovarian, colorectal, or the CNS.
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Page/Page column 34
(2010/07/10)
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- COMPOUNDS
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The present invention provides the use of a compound of the Formula: (I) wherein R1 is C1-5 alkoxy, OCOC1-3Alkyl, O(CH2)2O(CH2)2O(CH2)2OMe, O(CH2)2O(CH2)2O(CH2)2OH or OH; R2 is H, (CH2)nOH, OCH3, Hal or (II) or (III) R3 is H or (CH2)nOH; and R4 is C1-6 alkyl, optionally substituted by one or more of Hal, OH, COCH3, NH2, NHCH3, NHMe, NMe2, OCOCH3, CO2H or esters or amides thereof where n is 1-5; and pharmaceutically acceptable salts thereof, in the manufacture of a medicament for use in modulating PKB activity.
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Page/Page column 12
(2009/09/08)
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- PROCESS FOR THE PREPARATION OF CYCLOHEXANOL DERIVATIVES
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The present invention relates to a process for the preparation of cyclohexanol derivatives of the general formula (I), wherein R stands for a hydrogen atom or a methyl group, in a one-step process from a cyano compound of the general formula (II).
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Page/Page column 20-21; 24-25-26
(2009/12/27)
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- Stable-isotope dimethylation labeling combined with LC-ESI MS for quantification of amine-containing metabolites in biological samples
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One of the challenges associated with metabolome profiling in complex biological samples is to generate quantitative information on the metabolites of interest. In this work, a targeted metabolome analysis strategy is presented for the quantification of amine-containing metabolites. A dimethylation reaction is used to introduce a stable isotopic tag onto amine-containing metabolites followed by LC-ESI MS analysis. This labeling reaction employs a common reagent, formaldehyde, to label globally the amine groups through reductive animation. The performance of this strategy was investigated in the analysis of 20 amino acids and 15 amines by LC-ESI MS. It is shown that the labeling chemistry is simple, fast (13C-dimethylation does not show any isotope effect on either RPLC or HILIC LC, indicating that 13C-labeling is a preferred approach for relative quantification of amine-containing metabolites in different samples. The isotopically labeled 35 amine-containing analogues were found to be stable and proved to be effective in overcoming matrix effects in both relative and absolute quantification of these analytes present in a complicated sample, human urine. Finally, the characteristic mass difference provides additional structural information that reveals the existence of primary or secondary amine functional groups in amine-containing metabolites. As an example, for a human urine sample, a total of 438 pairs of different amine-containing metabolites were detected, at signal-to-noise ratios of greater than 10, by using the labeling strategy in conjunction with RP LC-ESI Fourier-transform ion cyclotron resonance MS.
- Guo, Kevin,Ji, Chengjie,Li, Liang
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p. 8631 - 8638
(2008/03/15)
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- Aplysamine-1 and related analogs as histamine H3 receptor antagonists
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Aplysamine-1 (1), a marine natural product, was synthesized and screened for in vitro activity at the human and rat histamine H3 receptors. Aplysamine-1 (1) was found to possess a high binding affinity for the human H3 receptor (Ki = 30 ± 4 nM). Synthetic analogs of 1, including des-bromoaplysamine-1 (10) and dimethyl-{2-[4-(3-piperidin-1-yl- propoxy)-phenyl]-ethyl}-amine (13), were potent H3 antagonists.
- Swanson, Devin M.,Wilson, Sandy J.,Boggs, Jamin D.,Xiao, Wei,Apodaca, Richard,Barbier, Ann J.,Lovenberg, Timothy W.,Carruthers, Nicholas I.
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p. 897 - 900
(2007/10/03)
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- Turbotoxins A and B, novel diiodotyramine derivatives from the Japanese gastropod Turbo marmorata
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Bioassay-guided separation of the aqueous ethanol extract of the viscera of the Japanese gastropod Turbo marmorata resulted in the isolation of two toxins, turbotoxins A and B. Their structures were determined by spectral analysis and confirmed by organic synthesis to be diiodotyramine derivatives. Turbotoxins A and B exhibited acute toxicity against ddY mice, with LD99 values of 1.0 and 4.0 mg/kg, respectively. The structure-toxicity relationships of turbotoxins were examined, and it was proved that the iodine atoms and trimethylammonium groups are important for its acute toxicity. Turbotoxin A inhibits acetylcholinesterase with an IC50 of 28 μM. (C) 2000 Elsevier Science Ltd.
- Kigoshi, Hideo,Kanematsu, Kengo,Yokota, Kyoko,Uemura, Daisuke
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p. 9063 - 9070
(2007/10/03)
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- Turbotoxins A and B, novel diiodotyramine derivatives from the Japanese gastropod Turbo marmorata
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Bioassay-guided separation of the aqueous ethanol extract of the viscera of the Japanese gastropod Turbo marmorata resulted in the isolation of two toxins, turbotoxins A and B. The structures were determined by spectral analysis and confirmed by organic synthesis to be diiodotyramine derivatives. Turbotoxins A and B exhibited acute toxicity against ddY mice, with LD99 values of 1.0 and 4.0 mg/kg, respectively.
- Kigoshi, Hideo,Kanematsu, Kengo,Uemura, Daisuke
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p. 5745 - 5748
(2007/10/03)
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