- Structure-activity relationships and binding mode of styrylquinolines as potent inhibitors of HIV-1 integrase and replication of HIV-1 in cell culture
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Our prior studies showed that polyhydroxylated styrylquinolines are potent HIV-1 integrase (IN) inhibitors that block the replication of HIV-1 in cell culture at nontoxic concentrations. To explore the mechanism of action of these inhibitors, various novel styrylquinoline derivatives were synthesized and tested against HIV-1 IN and in cell-based assays. Regarding the in vitro experiments, the structural requirements for biological activity are a carboxyl group at C-7, a hydroxyl group at C-8 in the quinoline subunit, and an ancillary phenyl ring. However the in vitro inhibitory profile tolerates deep alterations of this ring, e.g. by the introduction of various substituents or its replacement by heteroatomic nuclei. Regarding the ex vivo assays, the structural requirements for activity are more stringent than for in vitro inhibition. Thus, in addition to an o-hydroxy acid group in the quinoline, the presence of one ortho pair of substituents at C-3' and C- 4', particularly two hydroxyl groups, in the ancillary phenyl ring is imperatively required for inhibitory potency. Starting from literature data and the SARs developed in this work, a putative binding mode of styrylquinoline inhibitors to HIV-1 IN was derived.
- Zouhiri, Fatima,Mouscadet, Jean-Fran?ois,Mekouar, Khalid,Desma?le, Didier,Savouré, Delphine,Leh, Hervé,Subra, Frédéric,Le Bret, Marc,Auclair, Christian,D'Angelo, Jean
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Read Online
- An efficient stereoselective total synthesis of (±)-trans-dihydronarciclasine
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A short and efficient stereoselective total synthesis of (±)-trans-dihydronarciclasine (1), a highly potent naturally occurring antineoplastic agent, was developed from readily available vanillin (7). The key intermediate of this new synthesis was a butenone derivative (11), from which the target molecule could be obtained in 14, mostly stereoselective, reaction steps. Our total synthesis has provided an easy and, up to now, the least expensive access to the title alkaloid.
- Varró, Gábor,Heged?s, László,Simon, András,Kádas, István
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Read Online
- Identification of an extracellular bacterial flavoenzyme that can prevent re-polymerisation of lignin fragments
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A significant problem in the oxidative breakdown of lignin is the tendency of phenolic radical fragments to re-polymerise to form higher molecular weight species. In this paper we identify an extracellular flavin-dependent dehydrolipoamide dehydrogenase from Thermobifida fusca that prevents oxidative dimerization of a dimeric lignin model compound, which could be used as an accessory enzyme for lignin depolymerisation.
- Rahmanpour, Rahman,King, Lloyd D.W.,Bugg, Timothy D.H.
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Read Online
- Design, synthesis and biochemical evaluation of novel 2-amino-3-(7-methoxybenzo[d][1,3]dioxol-5-yl)propanoic acid using Horseradish peroxidase (HRP) activity, cellular ROS inhibition and molecular docking study
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In this paper, we report the design, synthesis and biochemical evaluation of 2-amino-3-(7-methoxybenzo[d][1,3]dioxol-5-yl)propanoic acid 9, a myristicin derivative, from cheap and available vanillin as starting material. Compound 9 is identified as a potential precursor of natural brasiliamide derivatives. All the products are fully characterized. The crystal structure of the intermediate diethyl 2-acetamido-2-((7-methoxybenzo[d][1,3]dioxol-5-yl)methyl)malonate 16, a precursor of this amino acid, is obtained and presented. The interactions stabilizing the crystal packing of 16 were deeply analyzed by considering first the supramolecular stacking and finally, by analyzing the contacts descriptors on the Hirshfeld surface, the molecular fingerprint and the intermolecular energy. Different biochemical properties of the desired amino acid 9 and its selected precursors are investigated. In DPPH test, 9 showed the best anti-radical activity (IC50 = 80.91 μM). The enzymatic, HRP-H2O2/L012, chemiluminescence assay reveals excellent inhibitory effect on the peroxidase activity and a good antioxidant activity of all the tested compounds with the best activity for 9 (IC50 = 0.36 μM). The anti-peroxidase activity observed for compound 9 was confirmed by molecular docking exploration that allows to identify interactions in the HRP-9 complex. Docking results showed that 9 interacts with catalytic and active site residues, especially with Arg38, His42, Ser73, Phe68 and Pro139. Moreover, the inhibition of ROS production by activated HL-60 cells was moderately obtained with compounds 9 and 13. The MTS cell viability test reveals that all tested compounds, except myristicin aldehyde 13, were not cytotoxic indicating that the observed inhibition of ROS production of activated HL-60 cells was not due to cells death. Finally, physicochemical and ADME-Tox predictions suggested that compound 9 could be considered as promising drug candidate.
- Demonceau, Albert,Etsè, Koffi Sénam,Mouithys-Mickalad, Ange,Serteyn, Didier,Zaragoza, Guillermo
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- First synthesis of tabamides A–C and their derivatives: In vitro nitric oxide inhibitory activity
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The first synthesis of natural phenolic amides, tabamides A–C (1–3), and their derivatives (4–12) was accomplished using Stobbe condensation and amide coupling reactions as key steps. The in vitro nitric oxide (NO) inhibitory effects of these compounds in LPS-induced RAW-264.7 macrophages were evaluated as an indicator of anti-inflammatory activity. All compounds tested had a concentration-dependent inhibitory effect on NO production by RAW-264.7 macrophages without significant cytotoxicity. Compound 6, a tabamide A derivative (IC50 = 82.6 μM), followed by tabamide A (1, IC50 = 100.7 μM), was the most potent from the series. The present study revealed that tabamide A (1) could be considered as a lead structure to develop NO production-targeted anti-inflammatory agents.
- Damodar, Kongara,Jeon, Sung Ho,Lee, Jeong Tae,Shin, Sooyong
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supporting information
(2021/11/10)
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- An Acid-Catalyzed Epoxide Ring-Opening/Transesterification Cascade Cyclization to Diastereoselective Syntheses of (±)-β-Noscapine and (±)-β-Hydrastine
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An acid-catalyzed stereoselective epoxide ring-opening/intramolecular transesterification cascade cyclization reaction and N-Boc deprotection was found to be a successful strategy to construct the phthalide tetrahydroisoquinoline skeleton in one pot. Based on this strategy, the unified and highly diastereoselective routes for the total syntheses of (±)-β-Noscapine and (±)-β-Hydrastine were exploited.
- Li, Jihui,Liu, Yongxiang,Song, Xinjing,Wu, Tianxiao,Meng, Jiaxin,Zheng, Yang,Qin, Qiaohua,Zhao, Dongmei,Cheng, Maosheng
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supporting information
p. 7149 - 7153
(2019/09/30)
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- Highly Stereoselective Synthesis of trans -Dihydronarciclasine Analogues
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Several new trans -dihydronarciclasine analogues were stereo selectively synthesised by applying our feasible and efficient process developed recently. These new phenanthridone alkaloid derivatives were obtained in both racemic and optically active forms. During their enantioselective syntheses, high selectivities (up to 99% ee) were achieved by using (8 S,9 S)-9-amino(9-deoxy)epiquinine as an organocatalyst. The modifications, the introduction of ethoxy or methoxy groups, were made in ring A of the phenanthridone scaffold.
- Varró, Gábor,Mattyasovszky, Lenke,Grün, Alajos,Simon, András,Hegedüs, László,Kádas, István
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p. 625 - 643
(2017/11/27)
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- Synthesis and Pharmacological Evaluation of Noscapine-Inspired 5-Substituted Tetrahydroisoquinolines as Cytotoxic Agents
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A series of 5-substituted tetrahydroisoquinolines was synthesized via a 10-step linear synthesis to assess whether replacement of noscapine's southern isobenzofuranone with other moieties resulted in retained cytotoxic activity. One such molecule, 18g, bearing a para-methoxybenzyl functionality with N-ethylcarbamoyl substitution, produced cell-cycle arrest at the G2/M phase with an EC50 of 2.7 μM in the MCF-7 breast-cancer cell line, a 7-fold increase compared with that of noscapine (5). This molecule had similar activity (EC50 of 2.5 μM) against the resistant NCI/AdrRES cell line, demonstrating its potential to overcome or avert known resistance mechanisms, unlike current cytotoxic agents. Compound 18g was found to modify the drug-efflux activity of P-gp and, in combination studies, potentiate the antiproliferative activity of vinblastine. These results provide insights into structural modifications to noscapine that will guide future development toward more potent cytotoxic agents that are active against resistant cancer cells.
- Devine, Shane M.,Yong, Cassandra,Amenuvegbe, Dzifa,Aurelio, Luigi,Muthiah, Divya,Pouton, Colin,Callaghan, Richard,Capuano, Ben,Scammells, Peter J.
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supporting information
p. 8444 - 8456
(2018/09/25)
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- The First Enantioselective Total Synthesis of (-)-Trans-Dihydronarciclasine
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A feasible and enantioselective total synthesis of (-)-Trans-dihydronarciclasine [(-)-1], a highly biologically active alkaloid, was devised starting from vanillin (8). The key step of this new synthesis was an asymmetric, organocatalytic Michael addition, in which an optically active nitropentanone [(-)-13] was obtained from a butenone derivative (12). Excellent enantioselectivity (>99% ee) was achieved using the (8S,9S)-9-Amino(9-deoxy)epiquinine (16) organocatalyst. The target molecule can be prepared in 13 steps from compound (-)-13. The total synthesis has provided a facile and first access to the ent-form of naturally occurring (+)-Trans-dihydronarciclasine, a highly potent cytostatic alkaloid.
- Varró, Gábor,Hegedus, László,Simon, András,Balogh, Attila,Grün, Alajos,Leveles, Ibolya,Vértessy, Beáta G.,Kádas, István
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p. 1909 - 1917
(2017/06/28)
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- Methoxy group substitution on catechol ring of dopamine facilitates its polymerization and formation of surface coatings
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Deposition of polydopamine on substrates is a facile and effective method of surface modification and the deposited polydopamine can reduce silver ions to form silver nanoparticles (AgNPs) for antibacterial applications. However, polydopamine deposition is a time-consuming process that usually requires 24?h to produce a dense surface coating. Since oxidation of dopamine is critical for its polymerization, we hypothesize herein that substitution of an electron-donating group on the catechol ring of dopamine can enhance its oxidation potential and subsequently accelerate its polymerization. In this work, dopamine substituted with a 5-methoxy group (OMeDA) was prepared. OMeDA polymerized faster than dopamine under similar reaction conditions, resulting in a polymer coating of 13?nm thickness on a silicon surface after 8?h, compared to the 24?h required for dopamine to form a coating of similar thickness. A polymer layer with AgNPs can be directly formed on the silicon substrate after exposure to a solution containing OMeDA and silver nitrate. After 2?h exposure, the silver content on the modified surfaces prepared with OMeDA was 187% higher than that obtained with dopamine, and the antibacterial efficacy of the former against Staphylococcus aureus was correspondingly higher than that of the latter. This study demonstrates that OMeDA with an electron-donating group in the catechol ring offers improvements over dopamine for surface modification applications.
- Zhang, Jieyu,Cheah, Yong Shung,Santhanakrishnan, Sridhar,Neoh, Koon Gee,Chai, Christina L.L.
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- Total syntheses of the coumarin-containing natural products pimpinellin and fraxetin using Au(I)-catalyzed intramolecular hydroarylation (IMHA) chemistry
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The title natural products (1 and 2, respectively) have been synthesized by Au(I)-catalyzed intramolecular hydroarylation (IMHA) of the relevant aryl propiolate esters (e.g., 13), which were themselves formed by reaction of the corresponding phenols with either 3-(trimethylsilyl)propiolic acid or propiolic acid and N-(3-dimethylaminopropyl)-N′-ethylcarbodiimide hydrochloride or dicyclohexylcarbodiimide. (±)-Purpurasol (3) was readily derived from fraxetin (2) by established procedures.
- Cervi, Aymeric,Aillard, Paul,Hazeri, Nourallah,Petit, Laurent,Chai, Christina L. L.,Willis, Anthony C.,Banwell, Martin G.
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p. 9876 - 9882
(2013/10/22)
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- Cis -restricted 3-aminopyrazole analogues of combretastatins: Synthesis from plant polyalkoxybenzenes and biological evaluation in the cytotoxicity and phenotypic sea urchin embryo assays
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We have synthesized a series of novel cis-restricted 4,5-polyalkoxydiaryl- 3-aminopyrazole analogues of combretastatins via short synthetic sequences using building blocks isolated from dill and parsley seed extracts. The resulting compounds were tested in vivo in the phenotypic sea urchin embryo assay to reveal their antimitotic and antitubulin effects. The most potent aminopyrazole, 14a, altered embryonic cell division at 10 nM concentration, exhibiting microtubule-destabilizing properties. Compounds 12a and 14a displayed pronounced cytotoxicity in the NCI60 anticancer drug screen, with the ability to inhibit growth of multi-drug-resistant cancer cells.
- Tsyganov, Dmitry V.,Konyushkin, Leonid D.,Karmanova, Irina B.,Firgang, Sergei I.,Strelenko, Yuri A.,Semenova, Marina N.,Kiselyov, Alex S.,Semenov, Victor V.
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p. 1485 - 1491
(2013/09/23)
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- An efficient synthesis of a potent anti-inflammatory agent, viscolin, and its inducible nitric oxide synthase inhibitory activity
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A new and efficient synthetic pathway employed the aldol condensation between the acetophenone (3) and vanillin derivative (4) resulted in the precursor chalcone intermediate (14). The target compound viscolin (1) could be afforded through the hydrogenation of the chalcone and followed by deprotection. The present strategy described the development of a more efficient procedure that allowed large-scale production of viscolin for the further research of biological activity both in vitro and in vivo.
- Kuo, Ping-Chung,Chen, Yi-Hsien,Leu, Yann-Lii,Huang, Chieh-Hung,Liao, Yu-Ren,Lee, E.-Jian,Yang, Mei-Lin,Wu, Tian-Shung
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experimental part
p. 557 - 561
(2012/06/01)
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- A concise synthesis of viscolin, and its anti-inflammatory effects through the suppression of iNOS, COX-2, ERK phosphorylation and proinflammatory cytokines expressions
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In the present report, a concise synthesis of viscolin (1) has been achieved. The anti-inflammatory effect of viscolin was investigated in vitro and in vivo. Viscolin blocked the expression of iNOS and COX-2, and it also inhibited the ERK for the activation of NF-κB in LPS-stimulated RAW 264.7 macrophages. Western blotting and immunohistochemical analysis revealed that viscolin decreased Carr-induced iNOS and COX-2 expressions. These results could help to deduce the anti-inflammatory mechanisms.
- Huang, Guan-Jhong,Bhaskar Reddy, M. Vijaya,Kuo, Ping-Chung,Huang, Chieh-Hung,Shih, Hung-Cheng,Lee, E.-Jian,Yang, Mei-Lin,Leu, Yann-Lii,Wu, Tian-Shung
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experimental part
p. 371 - 378
(2012/03/26)
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- Synthesis and biological evaluation of novel N,N′-bis- methylenedioxybenzyl-alkylenediamines as bivalent anti-Alzheimer disease ligands
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A novel series of N,N′-bis-methylenedioxybenzyl-alkylenediamines 5a5g have been designed, synthesized and evaluated as bivalent anti-Alzheimer's disease ligands. The enzyme inhibition assay results indicated that compounds 5e5g inhibit both acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) in the micromolar range (IC50, 2.764.24 M for AChE and 3.025.14 M for BuChE), which was in the same potential as the reference compound rivastigmine (IC50, 5.50 M for AChE and 1.60 M for BuChE). It was found that compounds could bind simultaneously to the peripheral and catalytic sites of AChE. β-Amyloid (Aβ) aggregation inhibition assay results showed that compound 5e exhibited highest self-mediated Aβ fibril aggregation inhibition activity (40.3%) with a similar potential as curcumin (41.6%). It was also found that 5e5g did not affect neuroblastoma cell viability at the concentration of 50 μM.
- Luo, Wen,Li, Yan-Ping,Tan, Jia-Heng,Gu, Lian-Quan,Huang, Zhi-Shu
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scheme or table
p. 706 - 711
(2012/04/04)
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- Design, synthesis and evaluation of novel tacrine-multialkoxybenzene hybrids as dual inhibitors for cholinesterases and amyloid beta aggregation
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A new series of tacrine-multialkoxybenzene hybrids (9a-9n) were designed, synthesized and evaluated as dual inhibitors of cholinesterases (ChEs) and self-induced β-amyloid (Aβ) aggregation. All the synthesized compounds had high acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) inhibitory activity with IC50 values at the nanomolar range, which were much better than tacrine alone. A Lineweaver-Burk plot and molecular modeling study showed that these hybrids targeted both the catalytic active site (CAS) and the peripheral anionic site (PAS) of AChE. Besides, compounds 9a-9f with methylenedioxybenzene moiety showed higher self-induced Aβ aggregation inhibitory activity than a reference compound, curcumin. These compounds could be selected as multi-potent agents for further investigation to treat AD.
- Luo, Wen,Li, Yan-Ping,He, Yan,Huang, Shi-Liang,Tan, Jia-Heng,Ou, Tian-Miao,Li, Ding,Gu, Lian-Quan,Huang, Zhi-Shu
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scheme or table
p. 763 - 770
(2011/03/18)
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- Total synthesis of graphislactones A, C, D, and H, of ulocladol, and of the originally proposed and revised structures of graphislactones e and F
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Graphislactones A-H and the structurally related ulocladol are highly oxygenated resorcylic lactones produced by lichens and fungi. We present total syntheses of graphislactones A, C-F, H and of ulocladol. Graphislactones E, F, and H were synthesized for the first time. The spectra of graphislactones E and F synthesized as the originally proposed structures were not in agreement with published data. Consequently, revised structures for these compounds are proposed, whose correctness is unambiguously proven by total synthesis and comparison of the spectroscopic data. Key steps in all syntheses are Suzuki couplings for the construction of the central biaryl bond and Dakin reactions to supply further hydroxy groups required in these highly oxygenated substrates. Graphislactones A, C, and H, acylated graphislac- tone D and ulocladol were prepared in 8-11 steps with 7-20% yield starting with purchasable compounds, where the longest linear sequence consists of 5-9 steps. The syntheses are thus significantly shorter than the previously published syntheses of graphislactones A-D and of ulocladol. Graphis- lactones E and F were synthesized in 8 steps, where the longest linear sequences consist of 6 and 5 steps, respectively. They were isolated as the respective acetylated compounds with 25 and 10% yield.
- Altemoeller, Martina,Gehring, Timo,Cudaj, Judith,Podlech, Joachim,Goesmann, Helmut,Feldmann, Claus,Rothenberger, Alexander
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supporting information; experimental part
p. 2130 - 2140
(2009/09/29)
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- Antineoplastic agents. 578. synthesis of stilstatins 1 and 2 and their water-soluble prodrugs
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Efficient syntheses of 3,4-methylenedioxy-4′,5-dimethoxy-2′, 3′-dihydroxy-Z-stilbene (stilstatin 1, 2), 3,4,4′-trimethoxy- 2′,3′,5-trihydroxy-Z-stilbene (stilstatin 2, 5), and respective phosphate prodrugs have been summarized. Both 2 and 5 were accessed via a convergent step synthesis using phosphonium bromides 6 and 21 in Wittig reactions with 2,3- bis(tert-butyldimethylsilyloxy)-4′-methoxybenzaldehyde 14. Deprotection of silyl ethers 15 and 26 with TBAF furnished 2 and 5, respectively. Phosphorylation of 2 and 5 afforded the phosphoric acid intermediates 17 and 28 for prodrug development. These phosphoric acid precursors were employed in parallel series of reactions to produce a selection of metal cation prodrug candidates. The biological activities of stilstatins 1 (2)and2(5) and their respective prodrugs were evaluated against a panel of one murine (P388) and six human cancer cell lines. Compared to combretastatin A-2 (1), stilstatin 1 (2) has an additional vicinal hydroxy group on the B ring, the presence of which was detrimental to the cancer cell line potency; in vivo, however, compound 2 would be predicted to have greater anticancer activity resulting from the o-quinone mechanism of action analogous to that of combretastatin A-1 (4). The substitution of a hydroxy group for a methoxy group on the A ring of combretastatin A-1 (4), resulting in stilstatin 2 (5), gave rise to a modest level of inhibition consistent with that found for 4 against cancer cell lines.
- Pettit, George R.,Thornhill, Andrew,Melody, Noeleen,Knight, John C.
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scheme or table
p. 380 - 388
(2009/12/04)
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- Biosynthesis of yatein in Anthriscus sylvestris.
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Little is known about the biosynthesis of yatein, in spite of its importance as a typical heartwood lignan and a key biosynthetic intermediate of the antitumor lignan podophyllotoxin. The present study, based on individual administration of [13C]phenylalanine and deuterium labelled lignans and simultaneous administration of two distinct lignans labelled with deuterium atoms to Anthriscus sylvestris, established the two independent branch pathways from matairesinol, one to afford yatein via thujaplicatin, 5-methylthujaplicatin, and 4,5-dimethylthujaplicatin and the other to bursehernin via pluviatolide. The latter pathway did not lead to yatein, eliminating the presence of a metabolic grid from matairesinol to yatein.
- Sakakibara, Norikazu,Suzuki, Shiro,Umezawa, Toshiaki,Shimada, Mikio
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p. 2474 - 2485
(2007/10/03)
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- Radical formation and coupling of hydroxycinnamic acids containing 1,2-dihydroxy substituents
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Hydroxycinnamic acids involved in the deposition and cross-linking of plant cell-wall polymers do not usually contain 1,2-dihydroxy substituents, despite the presence of both 3,4-dihydroxycinnamic acid and 4,5-dihydroxy-3-methoxycinnamic acid as intermediates in the biogenesis of lignin. Since the O-methyl transferases, enzymes catalysing methylation, are targets for the genetic manipulation of lignin biosynthesis, the potential incorporation of these 1,2-dihydroxated substrates becomes increasingly significant. Using EPR spectroscopy, it was observed that 1,2-dihydroxy substituents did not have an inhibitory effect on radical formation. Increasing the extent of hydroxylation and methoxylation, resulted in an increased ease of substrate oxidation. Despite formation of the parent radicals, coupling did not proceed, under conditions that generally result in phenylpropanoid polymerisation. It is postulated that intermolecular radical-coupling reactions are inhibited due to rapid conversion to the o-quinone. In contrast, when methoxylated at C3, as in 4,5-dihydroxy-3-methoxycinnamic acid, radical coupling proceeds with the major product resulting from 8-O-3 radical coupling and formation of a substituted 2,3-dihydro-1,4-dioxin ring.
- Russell, Wendy R.,Burkitt, Mark J.,Scobbie, Lorraine,Chesson, Andrew
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p. 206 - 215
(2007/10/03)
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- A convenient synthesis of 3,4-dimethoxy-5-hydroxybenzaldehyde
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Synthesis of 3,4-dimethoxy-5-hydroxybenzaldehyde (1) in three steps from vanillin with the key step being a copper catalyzed hydrolysis of 5- bromovanillin to give 4,5-dihydroxy-3-methoxybenzaldehyde.
- Ellis, James E.,Lenger, Steven R.
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p. 1517 - 1524
(2007/10/03)
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- Chemical degradation products of lignin and humic substances. Part II: Synthesis, structure verification and liquid) chromatographic separation of chlorinated protocatechualdehydes (3,4-dihydroxybenzaldehydes], 5-hydroxyvanillins (3,4-dihydroxy-5-methoxybenzaldehydes) and gallaldehydes (3,4,5-trihydroxybenzaldehydes)
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All possible chloroprotocatechualdehydes, chlorogallaldehydes, 5-bromoprotocatechualdehyde and chloro-5-hydroxyvanillins (except 2-chloro-5-hydroxyvanillin) were synthesized. Their purity and structures were examined by liquid chromatography, mass spectrometry and other spectroscopic measurements. The details of the synthesis, liquid chromatographic separation and mass spectrometric features are discussed.
- Hyotylainen
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p. 1641 - 1656
(2007/10/03)
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- Preparation of 3-memory-4,5-methylenedioxybenzaldehyde
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3-Methoxy-4,5-methylenedioxybenzaldehyde is facilely and improvedly prepared by reacting 4,5-dihydroxy-3-methoxybenzaldehyde with a dihalomethane in a two-phase reaction medium and at a pH of from 7 to 12.
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- Structure of the Novel Insecticidal Sesquilignan, Haedoxan A
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Haedoxan A, a new insecticidal sesquilignan, was isolated from the root of Hae-doku-sou, Phyrma leptostachya L., and the structure was elucidated as 1-hydroxy-2--6--3,7-dioxabicyclooctane on the basis of spectroscopic and chemical information involving synthesis of its partial structures.Its relative stereochemistry was revealed to be (1S*, 2R*, 5R*,6S*, 2'R*, 3'R*) or 1S*, 2R*, 5R*, 2'S*, 3'S*).
- Taniguchi, Eiji,Imamura, Keiichi,Ishabashi, Fumito,Matsui, Toshio,Nishio, Akira
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p. 631 - 644
(2007/10/02)
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- ZINC-SILVER COUPLE: A MILD AND CONVENIENT REAGENT FOR REDUCTIVE DEHALOGENATION OF ARYL HALIDES
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Zn-Ag couple is a pertinent reagent for the reductive dehalogenation of aryl halide to arene.
- Chung, Chi Kong,Ho, Mei Sing,Lun, Kue Sun,Wong, Man On,Wong, Henry N. C.,Tam, Shang Wai
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p. 507 - 510
(2007/10/02)
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- Process of hydroxylation of an aromatic carbonyl compound
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An aromatic compound is hydroxylated by reacting the aromatic compound in an aqueous solvent with a triiodide salt to form a reaction mixture containing the corresponding iodoaromatic compound. The mixture is reacted, without separating the iodoaromatic compound, with a hydroxylating agent to form the corresponding hydroxy aromatic compound. The iodide salt, formed as a by-product of the reaction, is then separated for reuse in the process.
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