- Cobalt Nanoparticles-Catalyzed Widely Applicable Successive C?C Bond Cleavage in Alcohols to Access Esters
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Selective cleavage and functionalization of C?C bonds have important applications in organic synthesis and biomass utilization. However, functionalization of C?C bonds by controlled cleavage remains difficult and challenging because they are inert. Herein, we describe an unprecedented efficient protocol for the breaking of successive C?C bonds in alcohols to form esters with one or multiple carbon atoms less using heterogeneous cobalt nanoparticles as catalyst with dioxygen as the oxidant. A wide range of alcohols including inactive long-chain alkyl aryl alcohols undergo smoothly successive cleavage of adjacent ?(C?C)n? bonds to afford the corresponding esters. The catalyst was used for seven times without any decrease in activity. Characterization and control experiments disclose that cobalt nanoparticles are responsible for the successive cleavage of C?C bonds to achieve excellent catalytic activity, while the presence of Co-Nx has just the opposite effect. Preliminary mechanistic studies reveal that a tandem sequence reaction is involved in this process.
- Dai, Wen,Gao, Shuang,Li, Guosong,Luo, Huihui,Lv, Ying,Shang, Sensen,Wang, Lianyue
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- Highly Selective Oxidation and Depolymerization of α,γ-Diol-Protected Lignin
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Lignin oxidation offers a potential sustainable pathway to oxygenated aromatic molecules. However, current methods that use real lignin tend to have low selectivity and a yield that is limited by lignin degradation during its extraction. We developed stoichiometric and catalytic oxidation methods using 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) as oxidant/catalyst to selectively deprotect the acetal and oxidize the α-OH into a ketone. The oxidized lignin was then depolymerized using a formic acid/sodium formate system to produce aromatic monomers with a 36 mol % (in the case of stoichiometric oxidation) and 31 mol % (in the case of catalytic oxidation) yield (based on the original Klason lignin). The selectivity to a single product reached 80 % (syringyl propane dione, and 10–13 % to guaiacyl propane dione). These high yields of monomers and unprecedented selectivity are attributed to the preservation of the lignin structure by the acetal.
- Lan, Wu,de Bueren, Jean Behaghel,Luterbacher, Jeremy S.
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- Br?nsted Acid Catalyzed Tandem Defunctionalization of Biorenewable Ferulic acid and Derivates into Bio-Catechol
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An efficient conversion of biorenewable ferulic acid into bio-catechol has been developed. The transformation comprises two consecutive defunctionalizations of the substrate, that is, C?O (demethylation) and C?C (de-2-carboxyvinylation) bond cleavage, occurring in one step. The process only requires heating of ferulic acid with HCl (or H2SO4) as catalyst in pressurized hot water (250 °C, 50 bar N2). The versatility is shown on a variety of other (biorenewable) substrates yielding up to 84 % di- (catechol, resorcinol, hydroquinone) and trihydroxybenzenes (pyrogallol, hydroxyquinol), in most cases just requiring simple extraction as work-up.
- Bal, Mathias,Bomon, Jeroen,Liao, Yuhe,Maes, Bert U. W.,Sels, Bert F.,Sergeyev, Sergey,Van Den Broeck, Elias,Van Speybroeck, Veronique
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p. 3063 - 3068
(2020/02/05)
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- Sequential Cleavage of Lignin Systems by Nitrogen Monoxide and Hydrazine
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The cleavage of representative lignin systems has been achieved in a metal-free two-step sequence first employing nitrogen monoxide for oxidation followed by hydrazine for reductive C?O bond scission. In combining nitrogen monoxide and lignin, the newly developed valorization strategy shows the particular feature of starting from two waste materials, and it further exploits the attractive conditions of a Wolff-Kishner reduction for C?O bond cleavage for the first time. (Figure presented.).
- Altmann, Lisa-Marie,Heinrich, Markus R.,Hofmann, Dagmar,Hofmann, Laura Elena,Prusko, Lea
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- Effective Synthesis of 3,4-Diaryl-isoxazole-5-carboxamides and their Antiproliferative Properties
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A simple scalable procedure for the synthesis of 3,4-diaryl-isoxazole-5-carboxamides 6 under mild conditions from readily available material was developed. The targeted compounds 6, structural analogues of heat shock protein inhibitors, were obtained by the rearrangement of intermediate 3,4-diaryl-5-carboxamido-isoxazoline N-oxides 5. In contrast to carboxamido-isoxazoline oxides 5, base-catalyzed recyclization of 3,4-diaryl-5-(ethoxycarbonyl)isoxazoline N-oxides 9c unexpectedly yielded 5-hydroxy-1,2-oxazin-6-ones 17c instead of ethyl 3,4-diaryl-isoxazole-5-carboxylates 10. Crystal and molecular structure of 4-(2,5-dimethoxy-3,4-methylenedioxyphenyl)-5-hydroxy-3-phenyl-6H-1,2-oxazin-6-one 17c was established by single-crystal X-ray diffraction study. In a phenotypic sea urchin embryo assay, carboxamide 6f showed moderate antimitotic antitubulin activity compared to 5-unsubstituted 3,4-diarylisoxazoles 15, which featured strong microtubule destabilizing effect.
- Maksimenko, Anna S.,Kislyi, Victor P.,Chernysheva, Natalia B.,Strelenko, Yuri A.,Zubavichus, Yan V.,Khrustalev, Victor N.,Semenova, Marina N.,Semenov, Victor V.
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p. 4260 - 4270
(2019/07/12)
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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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- Iridium-catalysed primary alcohol oxidation and hydrogen shuttling for the depolymerisation of lignin
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Lignin is a potentially abundant renewable resource for the production of aromatic chemicals, however its selective depolymerisation is challenging. Here, we report a new catalytic system for the depolymerisation of lignin to novel, non-phenolic monoaromatic products based on the selective β-O-4 primary alcohol dehydrogenation with a Cp?Ir-bipyridonate catalyst complex under basic conditions. We show that this system is capable of promoting the depolymerisation of model compounds and isolated lignins via a sequence of selective primary alcohol dehydrogenation, retro-aldol (Cα-Cβ) bond cleavage and in situ stabilisation of the aldehyde products by transfer (de)hydrogenation to alcohols and carboxylic acids. This method was found to give good to excellent yields of cleavage products with both etherified and free-phenolic lignin model compounds and could be applied to real lignin to generate a range of novel non-phenolic monomers including diols and di-acids. We additionally show, by using the same catalyst in a convergent, one-pot procedure, that these products can be selectively channelled towards a single di-acid product, giving much simpler product mixtures as a result.
- Lancefield, Christopher S.,Teunissen, Lucas W.,Weckhuysen, Bert M.,Bruijnincx, Pieter C. A.
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p. 3214 - 3221
(2018/07/31)
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- Rational Design, Synthesis, and Biological Activity of N-(1,4-Benzoxazinone)Acetamide Derivatives as Potent Platelet Aggregation Inhibitors
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Inappropriate thrombus formation within blood vessels is the leading cause of mortality in the industrialized world. Platelet aggregation activated by thrombin may have close relationship with thrombosis. Based on our studies on the pharmacophoric role of 1,4-benzoxazine-3(4H)-one for desirable platelet aggregation inhibitory activity, we identified N-(4-ethyl-3-oxo-3,4-dihydro-2H-benzo[b][1,4]oxazin-7-yl)-2-(4-methylpiperazin-1-yl)acetamide (BOAP-AM6) and N-(4-butyl-3-oxo-3,4-dihydro-2H-benzo[b][1,4]oxazin-7-yl)-2-(4-(4-fluorophenyl)piperazin-1-yl)acetamide (BOAP-AM21) as platelet aggregation inhibitors with an IC50 of 8.93 and 8.67 μM, respectively, as potent as the positive control aspirin. A combination of structure–activity relationships studies and molecular modeling revealed that the molecule BOAP-AM6 interacted with the amino acid residue TYR166 and ARG214 in the binding site of GPIIb/IIIa receptor through hydrogen bond and compound BOAP-AM21 acted on the amino acid residue ASN215 and ALA218, both through the same approach as the reported potent molecules 7a and 7b.
- Xiang, Yi,Wang, Xiu-Hua,Yang, Quan,Tan, Jia-Lian,Jang, Hee-Jae,Zuo, Hua,Shin, Dong-Soo
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supporting information
p. 146 - 155
(2018/01/27)
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- Synthesis and acaricidal activities of scopoletin phenolic ether derivatives: Qsar, molecular docking study and in silico Adme predictions
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Thirty phenolic ether derivatives of scopoletin modified at the 7-hydroxy position were synthesized, and their structures were confirmed by IR,1H-NMR,13C-NMR, MS and elemental analysis. Preliminary acaricidal activities of these compounds against female adults of Tetranychus cinnabarinus (Boisduval) were evaluated using the slide-dip method. The results indicated that some of these compounds exhibit more pronounced acaricidal activity than scopoletin, especially compounds 32, 20, 28, 27 and 8 which exhibited about 8.41-, 7.32-, 7.23-, 6.76-, and 6.65-fold higher acaricidal potency. Compound 32 possessed the the most promising acaricidal activity and exhibited about 1.45-fold higher acaricidal potency against T. cinnabarinus than propargite. Statistically significant 2D-QSAR model supports the observed acaricidal activities and reveals that polarizability (HATS5p) was the most important parameter controlling bioactivity. 3D-QSAR (CoMFA: q2 = 0.802, r2 = 0.993; CoMSIA: q2 = 0.735, r2 = 0.965) results show that bulky substituents at R4, R1, R2 and R5 (C6, C3, C4, and C7) positions, electron positive groups at R5 (C7) position, hydrophobic groups at R1 (C3) and R2 (C4), H-bond donors groups at R1 (C3) and R4 (C6) will increase their acaricidal activity, which provide a good insight into the molecular features relevant to the acaricidal activity for further designing novel acaricidal agents. Molecular docking demonstrates that these selected derivatives display different bide modes with TcPMCA1 from lead compound and they interact with more key amino acid residues than scopoletin. In silico ADME properties of scopoletin and its phenolic ether derivatives were also analyzed and showed potential to develop as good acaricidal candidates.
- Luo, Jinxiang,Lai, Ting,Guo, Tao,Chen, Fei,Zhang, Linli,Ding, Wei,Zhang, Yongqiang
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- 1,3-dimethyl-7-substituted-quinazolinyl-2,4-diones, and synthesis method and application thereof
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The invention discloses 1,3-dimethyl-7-substituted-quinazolinyl-2,4-diones. The structural general formula of the compounds is disclosed in the specification, wherein R1 is hydrogen or ethyl; and R2 is a benzene ring, benzene ring derivative, heterocyclic ring or aliphatic hydrocarbon. Part of compounds have favorable inhibiting activities for Candida albicans, Aspergillus flavus, Torula histolytica and Aspergillus fumigatus. The compounds have obvious inhibiting activities for chitin synthetase, have favorable antibacterial effects, and can be used for preparing drugs for anti-pathogenic microorganisms.
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Paragraph 0056; 0057; 0058; 0059; 0060; 0095; 0096
(2017/07/31)
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- Facile and selective hydrogenolysis of β-O-4 linkages in lignin catalyzed by Pd-Ni bimetallic nanoparticles supported on ZrO2
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The β-O-4 linkage in lignin can be selectively cleaved by Pd-Ni bimetallic nanoparticles supported on ZrO2 using hydrogen gas as the hydrogen donor under ambient pressure and neutral conditions. Conspicuous enhancement in activity is observed compared with single nickel and palladium catalysts based on the results of experiments and characterization. Moreover, hydrogenation of the produced phenols is tuned by adjusting the amount of NaBH4. The catalyst can be reused over ten times in the model reaction and over five times in the hydrogenolysis of lignin without an obvious change in activity and selectivity.
- Zhang, Jia-Wei,Cai, Yao,Lu, Guo-Ping,Cai, Chun
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p. 6229 - 6235
(2016/12/03)
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- Photocatalytic Oxidation of Lignin Model Systems by Merging Visible-Light Photoredox and Palladium Catalysis
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Lignin valorization has long been recognized as a sustainable solution for the renewable production of aromatic compounds. Two-step oxidation/reduction strategies, whereby the first oxidation step is required to "activate" lignin systems for controlled fragmentation reactions, have recently emerged as viable routes toward this goal. Herein we describe a catalytic protocol for oxidation of lignin model systems by combining photoredox and Pd catalysis. The developed dual catalytic protocol allowed the efficient oxidation of lignin model substrates at room temperature to afford the oxidized products in good to excellent yields.
- K?rk?s, Markus D.,Bosque, Irene,Matsuura, Bryan S.,Stephenson, Corey R. J.
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supporting information
p. 5166 - 5169
(2016/10/14)
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- Direct Catalytic Asymmetric Aldol Reaction of an α-Azido Amide
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A direct aldol reaction of an α-azido 7-azaindolinylamide, promoted by a Cu-based cooperative catalyst, is documented. Aromatic aldehydes bearing an ortho substituent exhibited diastereodivergency depending on the nature of the chiral ligands used. Smooth reactions with ynals highlighted the broad substrate scope. A vicinal azido alcohol unit in the product allowed direct access to the corresponding aziridine and facile hydrolysis of the 7-azaindolinylamide moiety furnished enantioenriched β-hydroxy-α-azido carboxylic acid derivatives.
- Weidner, Karin,Sun, Zhongdong,Kumagai, Naoya,Shibasaki, Masakatsu
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supporting information
p. 6236 - 6240
(2015/05/20)
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- Isolation of functionalized phenolic monomers through selective oxidation and CO bond cleavage of the β-O-4 linkages in Lignin
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Functionalized phenolic monomers have been generated and isolated from an organosolv lignin through a two-step depolymerization process. Chemoselective catalytic oxidation of β-O-4 linkages promoted by the DDQ/tBuONO/ O2 system was achieved in model compounds, including polymeric models and in real lignin. The oxidized β-O-4 linkages were then cleaved on reaction with zinc. Compared to many existing methods, this protocol, which can be achieved in one pot, is highly selective, giving rise to a simple mixture of products that can be readily purified to give pure compounds. The functionality present in these products makes them potentially valuable building blocks.
- Lancefield, Christopher S.,Ojo, O. Stephen,Tran, Fanny,Westwood, Nicholas J.
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p. 258 - 262
(2015/02/19)
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- SELECTIVE AEROBIC ALCOHOL OXIDATION METHOD FOR CONVERSION OF LIGNIN INTO SIMPLE AROMATIC COMPOUNDS
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Described is a method to oxidize lignin or lignin sub-units. The method includes oxidation of secondary benzylic alcohol in the lignin or lignin sub-unit to a corresponding ketone in the presence of unprotected primarily aliphatic alcohol in the lignin or lignin sub-unit. The optimal catalyst system consists of HNO3 in combination with another Br?nsted acid, in the absence of a metal-containing catalyst, thereby yielding a selectively oxidized lignin or lignin sub-unit. The method may be carried out in the presence or absence of additional reagents including TEMPO and TEMPO derivatives.
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Paragraph 0068; 0069
(2014/09/03)
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- The synthesis of 4,7-disubstituted-2H-benzo[b][1,4]-oxazin-3(4H)-ones using Smiles rearrangement and their in vitro evaluation as platelet aggregation inhibitors
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A series of novel benzo[b][1,4]oxazin-3(4H)-one derivatives were synthesized as platelet aggregation inhibitors for structure-activity relationships (SAR) analysis. The synthetic pattern, involved Smiles rearrangement for the preparation of benzoxazine, was proven to be more efficient than the conventional methods. Biological evaluation demonstrated that among all the synthesized compounds, compound 9u (IC50 = 9.20 μM) exhibited the most potent inhibition activity compared with aspirin, the positive control (IC50 = 7.07 μM). Molecular docking revealed that these set of compounds could be the GPIIb/IIIa antagonist for that they could be situated in the binding site of GPIIb/IIIa receptor quite well.
- Xia, Shuai,Liu, Ji-Qiang,Wang, Xiu-Hua,Tian, Ye,Wang, Yu,Wang, Jing-Huan,Fang, Liang,Zuo, Hua
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supporting information
p. 1479 - 1483
(2014/03/21)
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- A photochemical strategy for lignin degradation at room temperature
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The development of a room-temperature lignin degradation strategy consisting of a chemoselective benzylic oxidation with a recyclable oxidant ([4-AcNH-TEMPO]BF4) and a catalytic reductive C-O bond cleavage utilizing the photocatalyst [Ir(ppy)2(dtbbpy)]PF6 is described. This system was tested on relevant lignin model substrates containing β-O-4 linkages to generate fragmentation products in good to excellent yields.
- Nguyen, John D.,Matsuura, Bryan S.,Stephenson, Corey R. J.
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supporting information
p. 1218 - 1221
(2014/02/14)
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- PREPARATION AND METHOD FOR USE IN THE TREATMENT OF RESPIRATORY DISEASES
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The present disclosure relates to a novel active compound having the formula Ia: solid preparations, uses and methods for the treatment or prevention of respiratory diseases comprising said compound as well as process of preparation thereof.
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Page/Page column 13; 14
(2014/09/29)
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- Chemoselective metal-free aerobic alcohol oxidation in lignin
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An efficient organocatalytic method for chemoselective aerobic oxidation of secondary benzylic alcohols within lignin model compounds has been identified. Extension to selective oxidation in natural lignins has also been demonstrated. The optimal catalyst system consists of 4-acetamido-TEMPO (5 mol %; TEMPO = 2,2,6,6-tetramethylpiperidine-N-oxyl) in combination with HNO3 and HCl (10 mol % each). Preliminary studies highlight the prospect of combining this method with a subsequent oxidation step to achieve C-C bond cleavage.
- Rahimi, Alireza,Azarpira, Ali,Kim, Hoon,Ralph, John,Stahl, Shannon S.
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p. 6415 - 6418
(2013/06/05)
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- Synthesis, spectral studies and anti-inflammatory activity of glycolamide esters of niflumic acid as potential prodrugs
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In order to reduce the gastric irritation caused by direct contract mechanism of the carboxylic acid group, a series of glycolamide esters of niflumic (CAS 4394-00-7) (1) have been prepared as biolabile prodrugs by reacting appropriate 2-chloroacetamides with niflumic acid. The required 2-chloroacetamides were obtained by the condensation of chloroacetyl chloride and corresponding amine. Their structures were confirmed by UV, IR and 1H NMR spectra. Selected compounds were evaluated for anti-inflammatory activity in carrageenan induced paw oedema in rats at the doses of 45, 90 and 150 mg/kg b.w. Prodrugs showed comparable anti-inflammatory activity (67.1-79.4%) at 150 mg/kg b.w. with respect to niflumic acid (70.3%) at 45 mg/kg b.w., indicating moderate release of niflumic acid in vivo. The highest activity was observed with diethylamine (4) and pyrrolidine (9) derivatives.
- Gadad, Andanappa K.,Bhat, Shailija,Tegeli, Varsha S.,Redasani, Vivek V.
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p. 817 - 821
(2007/10/03)
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- Bicyclic amide derivatives and their use as muscle relaxants
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Novel compounds of formula (1) together with their salts and solvates have a number of uses in medicine, in particular as central muscle relaxants.
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- Bicyclic amide derivatives and their use as muscle relaxants
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Novel compounds of formula (I) STR1 wherein R1, R2, R3 and R4 are each selected from hydrogen and fluoro and at least one and not more than two is fluoro; R5 is selected from hydrogen and C1 -C4 alkyl; R6 is selected from hydrogen, C1 -C4 ally and hydroxy; or R5 and R6 together with the ring carbon form a carbonyl group; R7 is selected from hydrogen and hydroxy, R8 and R9 are each selected from hydrogen, C1 -C4 alkyl and cyclo(C3 or C4) alkyl or together with the nitrogen form a morpholino group; and X is selected from a bond, methylene and --O-- and is always a bond or --O-- when any of R5, R6 and R7 is other than hydrogen and is always a bond when R5 and R6 together with the ring carbon form a carbonyl group; and their salts and solvates have a number of uses as central muscle relaxants. In particular, treatment of conditions associated with abnormally raised skeletal muscle tone. They are of special value in the relaxation of skeletal muscle in spastic, hypertonic and hyperkinetic conditions.
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- Amide derivatives and their therapeutic use
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Novel carbocyclic amides together with their salts, solvates and physiologically active derivatives which have a number of uses in medicine, in particular as central muscle relaxants, and in the treatment or prophylaxis of anxiety, inflammation, arthritis and pain.
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- An efficient synthesis of 6-formyl-1,2-dihydro-2-oxo-3-pyridinecarboxylic acid and some carbonyl derivatives of it and its 6-acetyl homologue
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Starting with 1,1-dimethoxy-2-propanone (1), 6-formyl-1,2-dihydro-2-oxo-3-pyridinecarboxylic acid (5a) has been prepared in large quantities by a highly efficient, 4-step synthesis. This compound, along with its one carbon homologue, 6-acetyl-1,2-dihydro-2-oxo-3-pyridinecarboxylic acid (5b) has been reacted with several carbonyl derivative forming reagents to provide a series of side chains for β-lactams. Among these carbonyl derivatives are styrylamides which were prepared from Wittig and Horner-Emmons reagents. The preparation of the phosphonium salts and phosphonate esters is also described.
- Sanchez,Mich,Huang
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p. 297 - 303
(2007/10/02)
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- Electroorganic Reactions. 38. Mechanism of Electrooxidative Cleavage of Lignin Model Dimers
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The mechanisms for oxidative cleavage of several phenolic ethers, models for lignins, have been investigated by a detailed comparison of the results of anodic oxidation at nickel anodes in alkaline electrolyte with that of oxidation in acetonitrile in the presence of a triarylamine redox catalyst.The latter reaction is unambiguously initiated by single-electron transfer (SET), and in this case the major product of cleavage is aldehyde (vanillin or syringaldehyde derivatives).At nickel anodes polymerization is predominant although the aldehydes are formed together with larger amounts of the corresponding carboxylic acids.Combinations of 4-hydroxyl, α-keto, β-O-aryl, and β-hydroxymethyl functionality are shown to be crucial for the oxidation at nickel; the carboxylic acid formation probably involves a route with initial hydrogen atom abstraction at the surface.Important chemical conversions precede and accompany oxidation in alkaline media, and these are associated with the propensity for polymerization.
- Pardini, Vera L.,Smith, Carmen Z.,Utley, James H. P.,Vargas, Reinaldo R.,Viertler, Hans
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p. 7305 - 7313
(2007/10/02)
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- Oxidation of Lignin Model Compounds Using Single-Electron-Transfer Catalysts
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The single-electron-transfer oxidation of model compounds representative of the arylglycerol β-aryl ether and 1,2-diarylpropane linkages of lignin has been examined by using Co(II), Mn(II), or Co(II)/Mn(II) as catalysts.Catalytic oxidation of 1-(3,4-dimethoxyphenyl)-2-(2-methoxyphenoxy)propane-1,3-diol (DMMP) in 80percent acetic acid with 500 psi of 4percent oxygen in nitrogen and at 170 deg C resulted predominantly in products of Cα-Cβ bond cleavage when using Co(II)/Mn(II) as catalyst.Cα-Cβ bond cleavage of DMMP results from an initial single-electron oxidation toproduce an intermediate aromatic radical cation; in the absence of oxygen and catalyst, acid-catalyzed β-aryl ether cleavage was the predominant reaction pathway.Dihydroanisoin (DHA) and 1,2-bis(4-methoxyphenyl)propane-1,3-diol (BMPD) were oxidized by stoichiometric quantities of Co(III) to give solely products of Cα-Cβ bond cleavage but produced only acid-catalyzed dehydration products under reaction conditions necessary for catalytic oxidation.The application of this oxidation reaction as a replacement for chlorine bleaching of paper pulp is discussed.
- DiCosimo, Robert,Szabo, Hsiao-Chiung
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p. 1673 - 1679
(2007/10/02)
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- Stereoselective Syntheses of Lignin Model Compounds of the β-0-4 and β-1 Types
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The preparation of erythro forms of lignin model compounds of the β-0-4 type by hydroboration of α-aryloxycinnamic acids, using a borate dimethyl sulfide complex as a reagent, has been studied.The erythro form of 1-(4-hydroxy-3-methoxyphenyl)-2-(2-methoxyphenoxy)-1,3-propanediol was obtained in a yeild of about 50percent.Acid-catalyzed rearangements of chalcone oxides result in the formation of α-formyldesoxibenzoins which give 1,2-diaryl-1,3-propanediols on borohydride reduction.The synthesis of the erythro forms of 1,2-bis(4-hydroxy-3-methoxyphenyl)-1,3-propanediol and 1,2-bis(4-hydroxy-3,5-dimethoxyphenyl)-1,3-propanediol by this reaction route is discribed; 1,2-diaryl-1,3-propanediols represent lignin model compounds for the β-1 type of structure.
- Ahvonen, Toivo,Brunow, Goesta,Kristersson, Per,Lundquist, Knut
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p. 845 - 850
(2007/10/02)
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