- Pyromeconic acid and its glucosidic derivatives from leaves of Erigeron annuus, and the siderophile activity of pyromeconic acid.
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3'-O-Caffeylerigeroside (pyromeconic acid 3-O-beta-D-glucoside 3'-O-caffeyl ester) was obtained from the leaves of Erigeron annuus as a new pyromeconic acid derivative, and its structure was elucidated. Together with the gamma-pyrone derivative, pyromeconic acid (3-hydroxy-4H-pyran-4-one) and its beta-glucoside (erigeroside) were also isolated from the aerial parts of E. annuus. The siderophile activity of pyromeconic acid was also studied.
- Hashidoko
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- Synthesis method of 3-(benzyloxy)-4-oxo-4H-pyran-2-carboxylic acid
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The invention discloses a synthesis method of 3-(benzyloxy)-4-oxo-4H-pyran-2-carboxylic acid. The synthesis method takes furfuryl alcohol as a starting raw material and four-step reaction including rearrangement, addition, hydroxyl protection and oxidization is carried out; the total mol yield of a synthesis route is greater than 32 percent; the synthesis method has the characteristics of relatively moderate reaction conditions and the like, and the yield and purity of the 3-(benzyloxy)-4-oxo-4H-pyran-2-carboxylic acid are remarkably improved; meanwhile, the synthesis method has the advantagesof detailed technological operation steps, specific parameters, controllable conditions and stable technology, and can realize industrial large-batch production.
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Paragraph 0024; 0028; 0032; 0036
(2019/04/02)
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- Method for preparing ethyl maltol from corn cobs with furfuryl alcohol process
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The invention discloses a method for preparing ethyl maltol from corn cobs with a furfuryl alcohol process in the technical field of chemical synthesis. The method comprises the steps as follows: preparing furfural from the corn cobs with a two-step method; generating of furfuryl alcohol from furfural through a reaction: furfural and a platinum-loaded nitrogen-doped graphene material are placed in a reaction device, distilled water is added, hydrogen is introduced, and the mixture reacts at 90-160 DEG C for 4-8 h and furfuryl alcohol is prepared; preparing pyromeconic acid from furfuryl alcohol through chlorination and isomerization reactions; preparing hydroxyethyl maltol through condensation; finally, preparing ethyl maltol through reduction: heating is performed continuously after reaction for distilling off an ethanol aqueous solution, the temperature is increased for distilling off crude ethyl maltol, chloroform is added to the crude ethyl maltol for dissolving the crude ethyl maltol, the solution is cooled to 0 DEG C for recrystallization, crystals are dried, and finished maltol is obtained. Pollution-free, green, environment-friendly and pure food-grade ethyl maltol which is high in yield and produces no wastewater basically is prepared with the preparation method; as the structure of the maltol is similar to that of the ethyl maltol, the preparation method can be general, and all that is required is to adjust other raw materials in the reactions.
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- Synthesis and optimization of N-heterocyclic pyridinones as catechol-O-methyltransferase (COMT) inhibitors
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A series of N-heterocyclic pyridinone catechol-O-methyltransferase (COMT) inhibitors were synthesized. Physicochemical properties, including ligand lipophilic efficiency (LLE) and c log P, were used to guide compound design and attempt to improve inhibitor pharmacokinetics. Incorporation of heterocyclic central rings provided improvements in physicochemical parameters but did not significantly reduce in vitro or in vivo clearance. Nevertheless, compound 11 was identified as a potent inhibitor with sufficient in vivo exposure to significantly affect the dopamine metabolites homovanillic acid (HVA) and dihydroxyphenylacetic acid (DOPAC), and indicate central COMT inhibition.
- Zhao, Zhijian,Harrison, Scott T.,Schubert, Jeffrey W.,Sanders, John M.,Polsky-Fisher, Stacey,Zhang, Nanyan Rena,McLoughlin, Debra,Gibson, Christopher R.,Robinson, Ronald G.,Sachs, Nancy A.,Kandebo, Monika,Yao, Lihang,Smith, Sean M.,Hutson, Pete H.,Wolkenberg, Scott E.,Barrow, James C.
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p. 2952 - 2956
(2016/06/06)
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- INHIBITORS OF CATECHOL O-METHYL TRANSFERASE AND THEIR USE IN THE TREATMENT OF PSYCHOTIC DISORDERS
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The present invention relates to 4-pyridinone compounds which are inhibitors of catechol O-methyltransferase (COMT), and are useful in the treatment and prevention of neurological and psychiatric disorders and diseases in which COMT enzyme is involved. The present invention also relates to pharmaceutical compositions comprising these compounds and the use of these compounds and compositions in the prevention or treatment of such diseases in which COMT is involved
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- VINYLOGOUS 4H-PYRONES AND THEIR USE IN PROMOTING PLANT GROWTH
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This invention resides in a hitherto unknown class of chemical compounds, 2H-furo[2,3-c]pyran-2-ones including derivatives and analogues thereof. It includes methods for making compounds within said class and includes, without limitation, at least the intermediates employed in the generation of said compounds. The invention also relates to the use of vinylogous 4H-pyrones, including but not limited to the hitherto unknown 2H-furo[2,3-c]pyran-2-ones. In one aspect the invention resides in a method comprising the step of: exposing biological plant material to at least a compound of the invention to promoting bioactivity within said material. In another aspect the invention resides in methods for promoting growth of plant material in, for example, smoke-responsive plant species by exposing said material to a compound of the invention. More specifically, the invention relates to the use of said compounds for promoting seed germination of a plant, for example, a smoke-responsive plant.
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Page/Page column 43
(2008/06/13)
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- Synthesis, physicochemical characterization, and biological evaluation of 2-(1'-hydroxyalkyl-3-hydroxypyridin-4-ones: Novel iron chelators with enhanced pFe3+ values
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The synthesis of a range of 2-(1'-hydroxyalkyl)-3-hydroxypyridin-4-ones as bidentate iron(III) chelators with potential for oral administration is described. The pK(a) values of the ligands and the stability constants of their iron(III) complexes have been determined. Results indicate that the introduction of a 1'-hydroxyalkyl group at the 2-position leads to a significant improvement in the pFe3+ values. Such an effect was found to be greater with the hydroxyethyl substituent than with the hydroxy-methyl substituent, particularly in the cases of 1-ethyl-2(1'-hydroxyethyl)-3- hydroxypyridin-4-one (pFe3+ = 21.4) and 1,6-dimethyl-2-(1'-hydroxyethyl)3- hydroxypyridin-4-one (pFe3+ = 21.5) where an enhancement on pFe3+ values in the region of two orders of magnitude is observed, as compared with Deferiprone (1,2-dimethyl-3-hydroxypyridin-4-one) (pFe3+ = 19.4). The ability of these novel 3-hydroxypyridin-4-ones to facilitate the iron excretion in bile was investigated using a [59Fe] ferritin-loaded rat model. Chelators and prodrug chelators possessing high pFe3+ values show great promise in their ability to remove iron under in vivo conditions.
- Liu, Zu D.,Khodr, Hicham H.,Liu, Ding Y.,Lu, Shu L.,Hider, Robert C.
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p. 4814 - 4823
(2007/10/03)
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- Synthesis, physicochemical properties, and biological evaluation of hydroxypyranones and hydroxypyridinones: Novel bidentate ligands for cell- labeling
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The synthesis of a range of hydroxypyranones and hydroxypyridinones with potential for the chelation of indium(III) is described. The crystal structures of two of the indium complexes are presented. The distribution coefficients of the ligands and the corresponding iron(III), gallium(III), and indium(III) complexes are reported. Good linear relationships between the distribution coefficients of the iron and gallium complexes and iron and indium complexes were obtained. In contrast a nonlinear relationship was obtained between the distribution coefficient of the free ligand and the distribution coefficient of the three groups of complexes. This latter relationship was used to identify compounds with optimal cell labeling properties. Two such compounds both 6-(alkoxymethyl)-3-hydroxy-4H-pyran-4- ones have been compared with tropolone for their ability to label human leucocytes with 111In. The leucocyte labeling efficiencies of the selected ligands were greater and the in-vitro plasma stabilities were similar to that of 111In-tropolonate. These results suggest that the new bidentate ligands may offer advantages over those currently used for cell-labeling.
- Ellis, Beverley L.,Duhme, Anne K.,Hider, Robert C.,Hossain, M. Bilayet,Rizvi, Safia,Van Der Helm, Dick
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p. 3659 - 3670
(2007/10/03)
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- STUDIES TOWARDS 3,4-DIMETHOXY-1-METHYL-1,2-DIHYDROPYRIDINE, SO CALLED ARECOLIDINE, OR ITS TAUTOMERS
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Different synthetic paths towards the title compound (2) lead to intermediates (3, 11, 13, 14, 15, and 17).All of these, but especially 3 and 14 are very close to the target molecule or its tautomers.These, however, turn out to be too unstable for isolation.Thus, the structure of the compound described as arecolidine must be wrong.
- Dehmlow, Eckehard V.,Westerheide, Ralf
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p. 355 - 366
(2007/10/02)
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- Tobacco Smoke Chemistry. 4. A Mass Spectral Study of Alkyl 3-Hydroxy-4-pyrones
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3-Hydroxy-4-pyrone and a series of C-alkylated 3-hydroxy-4-pyrones have been synthesized and their behaviour under electron impact investigated.The fragmentation pathways were elucidated with the aid of accurate mass measurements, metastable ion analysis and deuterium labelling.All compounds examined gave a detectable molecular ion which undergoes a retro Diels-Alder type process accompanied by hydrogen transfer to give characteristic ions, which in many cases allow differentiation of positional isomers.Loss of carbon monoxide is encountered from several ions, but to any substantial extent from the molecular ions only in the cases of 3-hydroxy-4-pyrone and 5-hydroxy-2-methyl-4-pyrone.Instead, the more general fragmentation routes involve extrusion of a hydrogen or an alkyl radical from the molecular ion prior to the elimination of carbon monoxide.When the alkyl substituent in 2-alkyl-3-hydroxy- or 2-alkyl-5-hydroxy-4-pyrone has three or more consecutive carbons the molecular ion loses an alkene fragment by a McLafferty type of reaction.The even mass ions formed by this process constitute the base peak in most spectra of this type.Another rearrangement reaction giving even mass ions after loss of an alkene fragment, occurs when the alkyl substituent in the 2-alkyl-3-hydroxy-4-pyrones is branched at the α-carbon.Moreover, γ-bond cleavage of the alkyl side chain vicinal to the hydroxy group becomes important due to anchimeric assistance by the hydroxy group.
- Arnarp, Jan,Bielawski, Jacek,Dahlin, Britt-Marie,Dahlman, Olof,Enzell, Curt R.,Pettersson, Tore
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p. 916 - 926
(2007/10/02)
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