- Interaction of anthocyanins and anthocyanidins with α-hydroxyethyl radicals
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The products of interaction of anthocyanins and anthocyanidins with α-hydroxyethyl radicals have been studied using spectrophotometry and liquid chromatography-mass spectrometry. It has been shown that anthocyanins and anthocyanidins oxidize the hydroxyethyl radical. The anthocyanin transformation products are oxidized with oxygen to the parent anthocyanins. Anthocyanidins irreversibly react to form the corresponding hydroxybenzoic acid and presumably 4-(2-hydroxyethyl)resorcinol.
- Domnina,Fenin,Ermakov,Magomedbekov
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Read Online
- Iron-catalyzed arene C-H hydroxylation
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The sustainable, undirected, and selective catalytic hydroxylation of arenes remains an ongoing research challenge because of the relative inertness of aryl carbon-hydrogen bonds, the higher reactivity of the phenolic products leading to over-oxidized by-products, and the frequently insufficient regioselectivity. We report that iron coordinated by a bioinspired L-cystine-derived ligand can catalyze undirected arene carbon-hydrogen hydroxylation with hydrogen peroxide as the terminal oxidant. The reaction is distinguished by its broad substrate scope, excellent selectivity, and good yields, and it showcases compatibility with oxidation-sensitive functional groups, such as alcohols, polyphenols, aldehydes, and even a boronic acid. This method is well suited for the synthesis of polyphenols through multiple carbon-hydrogen hydroxylations, as well as the late-stage functionalization of natural products and drug molecules.
- Cheng, Lu,Wang, Huihui,Cai, Hengrui,Zhang, Jie,Gong, Xu,Han, Wei
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- Method for promoting iron-catalyzed oxidation of aromatic compound carbon - hydrogen bond to synthesize phenol by ligand
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The method comprises the following steps: iron is used as - a catalyst metal; a sulfur-containing amino acid or cystine-derived dipeptide is a ligand; and under the common action of hydrogen peroxide as an oxidizing agent, an aromatic compound is synthesized to prepare a phenol. Under the action of an acid as an accelerant and hydrogen peroxide as an oxidizing agent, the aryl carbon - hydrogen bond is directly hydroxylated to form a phenolic compound, and the method for preparing the phenol by the catalytic oxidation reaction has a plurality of advantages. The reaction raw materials, the oxidant and the promoter are wide in source, low in price, environment-friendly and good in stability. The aromatic compound carbon - hydrogen bonds directly participate in the reaction to react in one step to form phenol. The reaction condition is mild, the functional group compatibility and the application range are wide. The reaction selectivity is good; under the optimized reaction conditions, the target product separation yield can reach 85%.
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Paragraph 0072-0073; 0127
(2021/09/21)
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- Polycarboxylated compounds and compositions containing same
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Methods of selectively modifying lignin, polycarboxylated products thereof, and methods of deriving aromatic compounds therefrom. The methods comprise electrochemically oxidizing lignin using stable nitroxyl radicals to selectively oxidize primary hydroxyls on β-O-4 phenylpropanoid units to corresponding carboxylic acids while leaving the secondary hydroxyls unchanged. The oxidation results in polycarboxylated lignin in the form of a polymeric β-hydroxy acid. The polymeric β-hydroxy acid has a high loading of carboxylic acid and can be isolated in acid form, deprotonated, and/or converted to a salt. The β-hydroxy acid, anion, or salt can also be subjected to acidolysis to generate various aromatic monomers or oligomers. The initial oxidation of lignin to the polycarboxylated form renders the lignin more susceptible to acidolysis and thereby enhances the yield of aromatic monomers and oligomers obtained through acidolysis.
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Page/Page column 17-22
(2021/06/09)
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- Terpenoid and phenolic constituents from the roots of Ilex pubescens
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Five new metabolites, including two monoterpene glycosides Pubescenosides L–M (1–2) and three phenolic glycosides, Pubescenosides N-P (3–5), along with nineteen known ones, including liganoids, hemiterpenoids and caffeoylquinic acid derivates, were isolated from the roots of Ilex pubescens. Their structures were elucidated from extensive spectroscopic analysis, including 1D and 2D NMR experiments. This study is the first to report monoterpene glycosides with β-pinene aglycone in Aquifoliaceae. Nine of these compounds were evaluated in vitro for their anti-platelet aggregation activities. Among them, compounds 3 and 4 showed moderate inhibitory activities on ADP-induced blood platelet aggregation [inhibition (%): 32.3 and 33.6, respectively] as compared to aspirin.
- Zhou, Xu-Dong,Xu, Xiang-Wei,Xi, Yi-Yuan,Zhou, Yuan
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- Transition-metal-free conversion of lignin model compounds to high-value aromatics: Scope and chemoselectivity
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An efficient and straightforward reaction protocol for the conversion of lignin model compounds was developed based on a simple system consisting of a base, oxygen, and a green solvent under mild conditions in the absence of metals. This protocol was successfully applied to the cleavage of both 'β-O-4' dimeric and trimeric compounds, and a controlled selective degradation was achieved depending on the bond type. The feasibility of this method to provide aromatic compounds in high yields from lignin by a sequential oxidative dehomologation reaction was clearly demonstrated.
- Lee, Tae Woo,Yang, Jung Woon
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p. 3761 - 3771
(2018/08/21)
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- Bis(methoxypropyl) ether-promoted oxidation of aromatic alcohols into aromatic carboxylic acids and aromatic ketones with O2 under metal- and base-free conditions
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We describe an eco-friendly, practical and operationally simple procedure for the bis(methoxypropyl) ether-promoted oxidation of aromatic alcohols into aromatic carboxylic acids and aromatic ketones with atmospheric dioxygen as the sole oxidant. This chemical process is clean with high conversion and good selectivity, and an external initiator, catalyst, additive and base are not required. The virtue of this reaction is highlighted by its easily available and economical raw materials and excellent functional group tolerance (acid-, base- and oxidant-labile groups).
- Liu, Kai-Jian,Jiang, Si,Lu, Ling-Hui,Tang, Ling-Li,Tang, Shan-Shan,Tang, Hai-Shan,Tang, Zilong,He, Wei-Min,Xu, Xinhua
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supporting information
p. 3038 - 3043
(2018/07/13)
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- Ruticarpsides A–C, three new ester glycosides from the fruits of Tetradium ruticarpum
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In the course of our ongoing phytochemical investigation on the n-butanol extract of the fruits of Tetradium ruticarpum (Rutaceae), three new compounds, ruticarpsides A–C (1–3), were obtained and their structures were elucidated by a comprehensive analysis of NMR and MS data. Compound 3 showed a weak inhibition effect on nitric oxide production in BV-2 microglial cells stimulated with lipopolysaccharide.
- He, Wei,Jiang, Yong,Zhao, Ming-Bo,Zeng, Ke-Wu,Tu, Peng-Fei
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p. 659 - 665
(2017/05/26)
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- A process for the preparation of eugenol
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The invention relates to the technical field of chemical synthesis, and in particular relates to a preparation method of a syringic acid. According to the method, a reaction can be carried out in a normal-temperature environment or at a low temperature value (40 DEG C) by selecting and matching raw materials, so that the preparation process of the syringic acid is low in energy consumption, and thus the production cost of the syringic acid is lowered. The method is simple in reaction aftertreatment, i.e., a catalyst, a solvent and a small amount of polyhydroxy benzoic acid generated in a reaction process, which have good water solubility, can be separated from the syringic acid product via a simple extraction operation, so that a purification operation does not need to be further carried out. Thus, the synthetic cost is lowered.
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Paragraph 0042-0048
(2017/01/12)
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- Method for selective demethylation of ortho-trimethoxybenzene compounds
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The invention relates to a method for selective demethylation of ortho-trimethoxybenzene compounds and provides a method for preparation of 2,6-dimethoxyphenol derivatives by selective demethylation of ortho-trimethoxybenzene in different substitution types. By taking substitutional or non-substitutional ortho-trimethoxybenzene as a raw material, taking ZrCl4 as a catalyst and taking anisole as an additive, a ratio of the raw material to the catalyst to the additive is optimized in a reaction process to realize selective demethylation at a low reaction temperature ranging from the room temperature to 60 DEG C. The method has the advantages of mild reaction conditions, safety, reliability, low cost and easiness in operation and acquisition of the additive and the catalyst for reaction, simplicity and easiness in separation of reaction products, wide substrate application range and the like. The method effectively improves reaction safety and controllability and has an extensive application prospect in preparation of medicines, material intermediates and fine chemicals.
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Paragraph 0017
(2017/04/03)
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- A comprehensive investigation of guaiacyl-pyranoanthocyanin synthesis by one-/two-dimensional NMR and UPLC-DAD-ESI-MSn
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In red and rosé wines, the grape anthocyanins are progressively converted to more stable pigments, including phenylpyranoanthocyanins. One-/two-dimensional NMR and UPLC-DAD-ESI-MSn measurements were used to monitor the synthesis of guaiacylpyranomalvidin 3-O-glucoside from malvidin 3-O-glucoside and vinylguaiacol in model solutions and identify the products formed during the reaction. The highest conversion rates (30%, determined by 1H qNMR) were obtained with a small excess of vinylguaiacol in methanol/water (70/30) at pH 3 and 35 °C. Two reaction pathways competed with the formation of guaiacylpyranomalvidin 3-O-glucoside. The first one only concerns malvidin 3-O-glucoside and consists in C-ring cleavage with formation of malvone and smaller molecular weight breakdown products. This pathway is favored at higher pH and incubation temperature. At lower pH values or in the presence of large vinylguaiacol excess, faster consumption of malvidin 3-O-glucoside resulted from the formation of more complex pyranoanthocyanins substituted by vinylguaiacol oligomers.
- Vallverdú-Queralt, Anna,Meudec, Emmanuelle,Ferreira-Lima, Nayla,Sommerer, Nicolas,Dangles, Olivier,Cheynier, Véronique,Guernevé, Christine Le
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p. 902 - 910
(2016/01/25)
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- Formic-acid-induced depolymerization of oxidized lignin to aromatics
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Lignin is a heterogeneous aromatic biopolymer that accounts for nearly 30% of the organic carbon on Earth and is one of the few renewable sources of aromatic chemicals. As the most recalcitrant of the three components of lignocellulosic biomass (cellulose, hemicellulose and lignin), lignin has been treated as a waste product in the pulp and paper industry, where it is burned to supply energy and recover pulping chemicals in the operation of paper mills. Extraction of higher value from lignin is increasingly recognized as being crucial to the economic viability of integrated biorefineries. Depolymerization is an important starting point for many lignin valorization strategies, because it could generate valuable aromatic chemicals and/or provide a source of low-molecular-mass feedstocks suitable for downstream processing. Commercial precedents show that certain types of lignin (lignosulphonates) may be converted into vanillin and other marketable products, but new technologies are needed to enhance the lignin value chain. The complex, irregular structure of lignin complicates chemical conversion efforts, and known depolymerization methods typically afford ill-defined products in low yields (that is, less than 10-20wt%). Here we describe a method for the depolymerization of oxidized lignin under mild conditions in aqueous formic acid that results in more than 60wt% yield of low-molecular-mass aromatics. We present the discovery of this facile C-O cleavage method, its application to aspen lignin depolymerization, and mechanistic insights into the reaction. The broader implications of these results for lignin conversion and biomass refining are also considered.
- Rahimi, Alireza,Ulbrich, Arne,Coon, Joshua J.,Stahl, Shannon S.
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p. 249 - 252
(2015/03/30)
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- Aerobic oxidation of β-1 lignin model compounds with copper and oxovanadium catalysts
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The reactivity of homogeneous oxovanadium and copper catalysts toward aerobic oxidation of phenolic and nonphenolic β-1 lignin model compounds has been investigated. Aerobic oxidation of diastereomeric, nonphenolic β-1 lignin models (1T, 1E) using the six-coordinate vanadium complex (HQ) 2VV(O)(OiPr) (HQ = 8-oxyquinolinate) as a precatalyst in pyridine afforded ketone (3) and dehydrated ketone (4) derived from oxidation of the secondary alcohol. In contrast, using CuOTf/2,6-lutidine/ TEMPO (OTf = trifluoromethanesulfonate, TEMPO = 2,2,6,6-tetramethyl-piperidin-1- yl-oxyl) in toluene for the same reaction afforded 3,5-dimethoxybenzaldehyde (5) and 4-methoxybenzaldehyde (6) as major products resulting from C α-Cβ bond cleavage. Reactions of the corresponding phenolic lignin model compounds (2T, 2E) with 10 mol % CuOTf/2,6-lutidine/TEMPO gave ketone (9) as the major product, whereas 10 mol % (HQ)2VV(O)(OiPr) or a stoichiometric amount of CuOTf/2,6-lutidine/TEMPO yielded 2,6-dimethoxybenzoquinone (10) as the major product, arising from cleavage of the Caryl-Cα bond. Different selectivity was observed in the oxidation of 2T, 2E using the five-coordinate complex (dipic)VV(O)(OiPr) (dipic = dipicolinate), with α,β-unsaturated aldehyde (14) as the major product (formed from oxidation of the primary alcohol and dehydration). The key differences in chemoselectivity between the vanadium and copper catalysts in the oxidations of these phenolic and nonphenolic β-1 lignin models are discussed.
- Sedai, Baburam,Diaz-Urrutia, Christian,Baker, R. Tom,Wu, Ruilian,Silks, L. A. Pete,Hanson, Susan K.
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p. 3111 - 3122
(2014/01/06)
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- Two new neolignan glycosides from Pittosporum glabratum Lindl.
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Two new neolignan glycosides, named pittogoside A (1) and pittogoside B (2) were isolated from the roots of Pittosporum glabratum Lindl. Their structures, including the absolute stereochemistry, were determined on the basis of spectroscopic analysis and chemical evidence, with combination of circular dichroism.
- Zhao, Huanxin,Nie, Tiantian,Guo, Huanjie,Li, Jun,Bai, Hong
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experimental part
p. 240 - 243
(2012/07/27)
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- Biologically active bergenin derivatives from bergenia stracheyi
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New bergenin derivatives, bergecins A and B (1 and 2, resp.), have been isolated from the AcOEt-soluble fraction of Bergenia stracheyi, along with bergenin (3), and their structures were elucidated on the basis of 1H- and 13C-NMR spectra, and by COSY, HMQC, and HMBC experiments. Compound 2 showed potent inhibitory potential against the enzyme lipoxygenase, while 1 was moderately active. On the other hand, both compounds exhibited significant antioxidant activities in 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging assay. Copyright
- Siddiq, Farah,Fatima, Itrat,Malik, Abdul,Afza, Nighat,Iqbal, Lubna,Lateef, Mehreen,Hameed, Saira,Khan, Sher Wali
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body text
p. 91 - 98
(2012/04/10)
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- Cloning and heterologous expression of two aryl-aldehyde dehydrogenases from the white-rot basidiomycete Phanerochaete chrysosporium
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We identified two aryl-aldehyde dehydrogenase proteins (PcALDH1 and PcALDH2) from the white-rot basidiomycete Phanerochaete chrysosporium. Both PcALDHs were translationally up-regulated in response to exogenous addition of vanillin, one of the key aromatic compounds in the pathway of lignin degradation by basidiomycetes. To clarify the catalytic functions of PcALDHs, we isolated full-length cDNAs encoding these proteins and heterologously expressed the recombinant enzymes using a pET/Escherichia coli system. The open reading frames of both PcALDH1 and PcALDH2 consisted of 1503 nucleotides. The deduced amino acid sequences of both proteins showed high homologies with aryl-aldehyde dehydrogenases from other organisms and contained ten conserved domains of ALDHs. Moreover, a novel glycine-rich motif "GxGxxxG" was located at the NAD+-binding site. The recombinant PcALDHs catalyzed dehydrogenation reactions of several aryl-aldehyde compounds, including vanillin, to their corresponding aromatic acids. These results strongly suggested that PcALDHs metabolize aryl-aldehyde compounds generated during fungal degradation of lignin and various aromatic xenobiotics.
- Nakamura, Tomofumi,Ichinose, Hirofumi,Wariishi, Hiroyuki
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experimental part
p. 470 - 475
(2011/12/15)
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- Selective demethylation and debenzylation of aryl ethers by magnesium iodide under solvent-free conditions and its application to the total synthesis of natural products
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An efficient selective demethylation and debenzylation method for aryl methyl/benzyl ethers using magnesium iodide under solvent-free conditions has been developed and applied to the synthesis of natural flavone and biphenyl glycosides. A variety of functional groups including glycoside were tolerated under the reaction conditions. Experimental results indicated that the removal of an O-benzyl group was easier than that of an O-methyl group, regardless of wherever they were meta or para to the carbonyl. Thus selective debenzylation can be achieved for substrates bearing both benzyloxy and methoxy groups.
- Bao, Kai,Fan, Aixue,Dai, Yi,Zhang, Liang,Zhang, Weige,Cheng, Maosheng,Yao, Xinsheng
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scheme or table
p. 5084 - 5090
(2010/04/03)
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- Simple deprotection of acetal type protecting groups under neutral conditions
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Heating acetals with ethylene glycol causes the deprotection of acetal type protecting groups. When acetals such as MOM ethers, MEM ethers, and THP ethers were heated in ethylene glycol or propylene glycol, solvolysis proceeded smoothly to produce alcohols in excellent yield. This reaction is a very promising method for chemoselective deprotection of acetal type protecting groups.
- Miyake, Hideyoshi,Tsumura, Takatsugu,Sasaki, Mitsuru
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p. 7213 - 7215
(2007/10/03)
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- Biotransformation of sinapic acid by the green algae Stichococcus bacillaris 155LTAP and Ankistrodesmus braunii C202.7a
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Sinapic acid was bioconverted by the green alga Stichococcus bacillaris into 4-hydroxy-3,5-dimethoxybenzoic acid, 4-hydroxy-3,5-dimethoxybenzaldehyde and 4-hydroxy-3,5-dimethoxybenzylic alcohol. Incubation of sinapic acid in a culture of the alga Ankistrodesmus braunii gave 3,6-dihydroxy-2,4-dimethoxy-7H-benzocyclohepten-7-one, a new compound formed by bioconversion of thomasidioic acid, the primary oxidative product of sinapic acid.
- DellaGreca, Marina,Pinto, Gabriele,Pollio, Antonino,Previtera, Lucio,Temussi, Fabio
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p. 2779 - 2780
(2007/10/03)
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- Biosynthesis. Part 27.1,2 Colchicine: Studies of the phenolic oxidative coupling and ring-expansion processes based on incorporation of multiply labelled 1-phenethylisoquinolines
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Earlier research from our group had proved that the biosynthesis of colchicine and its tropolonoid relatives involves the oxidative ring-closure of a 1-phenethyltetrahydroisoquinoline, autumnaline, followed by extensive modification of the cyclised product. These steps pose many mechanistic and stereochemical questions which are set out in the Introduction. The sequel then provides the answers based on the results from a series of incorporation experiments on Colchicum plants involving multiply labelled forms of autumnaline and its biological precursors. These multiply labelled samples required the synthesis of eleven differently labelled tetrahydroisoquinolines; the methods used to introduce the labels are described. Autumnaline is shown to be present in Colchicum autumnale plants and labelled forms of some precursors of it are synthesised and studied. Taken together, the findings allow further definition of a substantial part of the biosynthetic pathway to colchicine and its relatives.
- McDonald, Edward,Ramage, Robert,Woodhouse, Robert N.,Underbill, Edward W.,Wetter, Leslie R.,Battersby, Alan R.
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p. 2979 - 2987
(2007/10/03)
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- A new convenient synthetic procedure for 4-allyl-2,6-dimethoxyphenol
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4-Allyl-2,6-dimethoxyphenol was synthesized from 4-hydroxy-2,6-dimethoxybenzoic acid and allylbromide by condensation under basic condition and by subsequent Claisen rearrangement.
- Li, Guoqing,Li, Zhan,Fang, Xiuhua
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p. 2569 - 2572
(2007/10/03)
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- Reactivity in the Para Oxo Ketene Route of Ester Hydrolysis. The Effect of Internal Nucleophilicity and the Irrelevance of B Strain
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The hydrolysis of 2,4-dinitrophenyl (DNP) esters of substituted 4-hydroxybenzoic acids obeys the equation kobsd = (ka + kb->)/(1 + +>/Ka) and involves a para oxo ketene intermediate.The ka term fits a Broensted equation against the pK of the 4-hydroxybenzoate (log ka = 1.15pKa - 11.71) provided the 2,6-positions of the benzoate are free.The ka term for the 2,6-dimethyl-4-hydroxybenzoate ester is 1015-fold larger than that for the parent 4-hydroxybenzoate ester.An electronic effect due to different hydroxyl pKa's may be calculated from the above linear free energy relationship to contribute 1.6percent of the discrepancy.The other component of the discrepancy is ascribed to a preferred alignment of the ester in the 2,6-dimethyl case perpendicular to the plane of the aromatic ring. The fused ketene in the microscopic reverse reaction has a LUMO acceptor orbital perpendicular to the plane of the ring, in agreement with our conclusions.Force-field calculations of nonbonding interactions indicate no strain release in the elimination mechanism giving rise to ka.The dramatic (107-fold) enhancement of the apparent second-order rate constant for alkaline hydrolysis of the 2,6-dimethyl ester compared with that of the corresponding 2',4'-dinitrophenyl 4-methoxy-2,6-dimethylbenzoate is due mostly to the steric strain imposed in the tetrahedral transition state for the latter reaction.This strain is not sufficient, however, to cause the normal BAc2 mechanism in the alkaline hydrolysis of mesitoates to change to a "square planar" concerted process.
- Thea, Sergio,Cevasco, Giorgio,Guanti, Giuseppe,Kashefi-Naini, Nasrin,Willams, Andrew
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p. 1867 - 1872
(2007/10/02)
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- A BIFLAVANONE FROM SEMECARPUS ANACARDIUM
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A new biflavanone, galluflavanone, has been isolated from the alcoholic extract of the nut shells of Semecarpus anacardium.It has been characterized through chemical and spectral data. - Key Word Index: Semecarpus anacardium; Anacardiaceae; biflavanones; 1H NMR and mass spectra; galluflavanone.
- Murthy, S. S. N.
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p. 2636 - 2638
(2007/10/02)
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- Synthesis along Biosynthetic Pathways. Part 2. Synthesis of Protostephanine
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The dienone protostephanone (3) is synthesised by phenol coupling or by Pschorr cyclisation from readily prepared tetrahydroisoquinolines, and the corresponding dienols (17) and (18) are converted by rearrangement, fragmentation, and reduction into protostephanine (4).This sequence mimics the natural pathway to the alkaloid.
- Battersby, Alan R.,Bhatnagar, Akil K.,Hackett, Peter,Thornber, Craig W.,Staunton, James
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p. 2002 - 2009
(2007/10/02)
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- Process for preparing pyrogallol
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Pyrogallol is prepared by (A) reacting a halo compound of formula STR1 where X represents Br or I, R1 represents hydrogen, secondary or tertiary alkyl of up to 10 carbon atoms, carboxy or alkoxycarbonyl of 2-5 carbon atoms and R2 represents hydrogen or alkyl of 1-4 carbon atoms, with an alkali metal alkoxide of formula ROM where M represents an alkali metal and R represents alkyl of 1-4 carbon atoms, to replace each X by OR, and then (B) dealkylating each OR and each OR2 where R2 represents alkyl of 1-4 carbon atoms and removing the R1 group where this is not hydrogen.
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- 2-Acyl-5-substituted thiatetrahydrofuran-4-ones
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Described are 2-acyl-5-substituted thiatetrahydrofuran-4-ones having the generic structure: STR1 wherein R1, R2, R1 ' and R2 ' are the same or different and each represents hydrogen or methyl and wherein R3 represents one of C1 -C9 alkyl, benzyl, phenyl, substituted or unsubstituted allyl having the structure: STR2 substituted or unsubstituted 3-furyl having the structure: (wherein R4 and R8 are the same or different and each represents hydrogen or methyl) hydroxy alkyl, oxoalkyl, hydroxycycloalkyl or oxocycloalkyl having the structure: STR3 (wherein R5 and R6, taken separately, represent hydrogen or C1 -C3 alkyl or R5 and R6, taken together, complete a cycloalkyl group and wherein Q is one of the moieties: STR4 The 2-acyl-5-substituted thiatetrahydrofuran-4-ones of our invention have organoleptic properties which make them useful for augmenting or enhancing the aroma or flavor of foodstuffs, tobaccos and the aroma of perfumes and perfumed articles.
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- Process for preparing 5-acyl-2-(furfurylthio)dihydro-2,5-dialkyl-3-[2H]furanones
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Described is a process for preparing 5-acyl-2-(furfurylthio)dihydro-2,5-dialkyl-3-[2H]furanones by reacting one or more dimers of a C4 -C6 alpha, beta alkanedione with furfurylmercaptan to form one or more 5-acyl-2-(furfurylthio)dihydro-2,5-dialkyl-3-[2H]furanones, said reaction taking place in an acidic medium and in the presence of an inert solvent. The processes of this invention give rise to compounds which can be used in flavor and aroma imparting, augmenting, modifying or enhancing compositions for foodstuffs, chewing gums, toothpastes, medicinal products and tobaccos and as foodstuff, chewing gum, toothpaste, medicinal product and tobacco aroma and flavor imparting, augmenting, enhancing or modifying materials.
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- Synthesis and pharmacological properties of a phthalide derivative containing methoxy groups.
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4,6-Dimethoxy-5-hydroxyphthalide 2 was obtained on three routes: by selective demethylation of 4,5,6-trimethoxyphthalide and by the action of formaldehyde on either syringic acid or acetylsyringic acid. Pharmacological tests carried out on rats showed that the product significantly increased bile excretion, its activity being five times higher than those of dehydrocholic acid.
- Borkowski,Kolodynska,Naciazek-Wieniawska,Wieniawski
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p. 243 - 251,245, 246
(2007/10/14)
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- Substituted benzofurans and benzothiophenes
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The compounds of this invention are substituted benzofurans and benzothiophenes having pharmacological activity. In particular, these compounds have coronary vasodilator activity and are useful in the treatment angina pectoris.
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