- Oxidation of phenols to quinones by bis(trifluoroacetoxy)iodobenzene
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Bis (trifluoroacetoxy) iodobenzene oxidizes phenols into quinones in good yield.
- Barret,Daudon
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- Efficient synthesis of substituted quinoline-5,8-quinones from 8-hydroxyquinolines by photooxygenation
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Substituted quinoline-5,8-quinones were obtained in good yield by photooxygenation of substituted 8-hydroxyquinolines.
- Cossy, Janine,Belotti, Damien
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- G-quadruplex and duplex DNA binding studies of novel Ruthenium(II) complexes containing ascididemin ligands
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In this paper, three new Ruthenium(II) polypyridyl complexes containing ascididemin (ASC) as main ligand have been synthesized and characterized. Their interactions with different G-quadruplex (Htelo, c-myc and c-kit) (Htelo: human telomeric DNA, c-myc: cellular-myelocytomatosis viral oncogene, c-kit: oncogene c-kit promoter sequences) and duplex (ds26) DNA sequences were comparatively studied with the free ligand ASC by a series of spectroscopic techniques including UV–vis (ultraviolet-visible) spectroscopy, FID (fluorescent intercalator displacement) assay, and FRET (fluorescence resonance energy transfer) melting assay. Molecular docking studies were also performed to support the binding mode of the compounds with G-quadruplex DNA. Results indicated that [Ru(bpy)2ASC]·(PF6)2 (1), [Ru(phen)2ASC]·(PF6)2 (2), [Ru(tatp)2ASC]·(PF6)2 (3) (bpy = 2,2′?bipyridine, phen = 1,10?phenanthroline, tatp = 1,4,8,9?tetra?aza?triphenylene) and ASC can effectively bind G-quadruplex and duplex DNA and stabilization ability lies in the order 3 > 2 > 1 > ASC. Complex 3 was determined to be the most promising candidate for further in vitro studies and potential anticancer drug.
- Wumaier, Maierhaba,Shi, Jing-Jing,Yao, Tian-Ming,Hu, Xiao-Chun,Gao, Ru-Ru,Shi, Shuo
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- Reaction of 2,5-dimethylpyrroles with quinones. Synthesis of new pyrrolylquinones dyes
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The reaction of 1,4-naphthoquinone (1) with 2,5-dimethylpyrroles (7a-7d) gives only 3-(1,4-naphthoquinonyl)-2,5-dimethylpyrroles. Extending the reaction to other quinones: 5-hydroxy-1,4-naphthoquinone (2), 1,2-naphthoquinone (3), quinoline-5,8-dione (4) and quinoxaline-5,8-dione (5), of which nothing was known, allows the synthesis of new pyrrolylquinones.
- Lion, Claude,Baudry, Richard,Hedayatullah, Mir,Da Conceicao, Louis,Genard, Sylvie,Maignan, Jean
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- Synthesis and biological evaluation of novel isothiazoloquinoline quinone analogues
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Natural quinones and their analogues have attracted growing attention because of their novel anticancer activities. A series of novel isothiazoloquinoline quinone analogues were synthesized and evaluated for antitumor activities against four different kind of cancer cells. Among them, isothiazoloquinolinoquinones inhibited cancer cells proliferation effectively with IC50 values in the nanomolar range, and isothiazoloquinolinoquinone 13a induced the cell apoptosis. Further exploration of possible mechanism of action indicates that 13a not only activates ROS production through NQO1-directed redox cycling but also inhibits the phosphorylation of STAT3. These findings indicate that 13a has potential use for the development of new skeleton drug candidate as an efficient substrate of NQO1 and STAT3 inhibitor.
- Chen, Ling,Gao, Jin-Lei,Hao, Ying,Kong, Fan-Rong,Liu, Hong-Dou,Liu, Li-Jun,Liu, Su-You,Luo, Zhi-Yong,Ma, Da-You,Wang, Liu-Liu,Xie, Yuan-Zhu,Zou, Zi-Zheng
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- Probing the TiO2 photocatalytic mechanisms in water purification by use of quinoline, photo-fenton generated OH. radicals and superoxide dismutase
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In an attempt to improve our understanding of the basic mechanisms of the degradation of aromatic pollutants in water by TiO2 photocatalysis, quinoline (benzo[b]pyridine) was selected as a molecular probe, principally because of the difference in electron density over its two rings. This study was based on the identification and quantification of the primary products or principal secondary products of quinoline degradation either by TiO2 photocatalysis at pH 3 and 6 or by OH. radicals generated via the photo-Fenton reaction (Fe(II/III)-H2O2-UV) at pH 3. In this latter case, the three major products were those expected from the preferential electrophilic attack of OH. radicals on the electron-richer benzene moiety, viz., 5-, and 8-hydroxyquinolines and quinoline-5,8-dione derived from them. TiO2 photocatalysis did not yield this dione, and at the same percentages of degraded quinoline, the amounts of 5-hydroxyquinoline were lower by a factor of ca. 2 at pH 3 and ca. 10 at pH 6 (those of the 8-isomer were also decreased but no accurate measurements were obtained). In addition, at pH 6, we observed marked increases in the amounts of products corresponding to the oxidation of the pyridine moiety, viz., 4-quinolinone and especially 2-aminobenzaldehyde (the major product) and its N-formyl derivative. These results show that oxidative steps in TiO2 photocatalysis do not involve only OH. radicals. It was also observed that, at pH 6, superoxide dismutase (SOD), which catalyzes the elimination of O2.- species, decreased the TiO2 photocatalytic rate of quinoline disappearance, almost suppressed the formation of 2-aminobenzaldehyde, and lowered the amount of 4-quinolinone. The SOD and pH effects suggest a mechanism involving quinoline activation by hole transfer, followed by superoxide addition to the resulting radical cation. The nucleophilic character of superoxide implies addition to the pyridine moiety, i.e., with a regioselectivity opposite that of the OH. radical pathway.
- Cermenati, Laura,Pichat, Pierre,Guillard, Chantal,Albini, Angelo
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- A new synthesis of quinoline-5,8-quinone
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Sensitised photo-oxidations of 8-hydroxy quinoline (1) or 5-hydroxy quinoline (2) gives quinoline-5,8-quinone (3) in 64-70% yield.
- Amarasekara, Ananda S.
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- Use of a readily removable auxiliary group for the synthesis of pyrrolidones by the palladium-catalyzed intramolecular amination of unactivated γ C(sp3)-H Bonds
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Easy on, easy off: Directing groups found to promote the palladium-catalyzed amination of γ C(sp3)-H and C(sp 2)-H bonds of secondary amides included 5-methoxy-8-aminoquinoline, which can be removed under mild conditions (see scheme; CAN=ceric ammonium nitrate). In conjunction with a β-C-H methylation or γ-C-H arylation step, the γ-C(sp3)-H amination provided access to complex pyrrolidones from readily available precursors. Copyright
- He, Gang,Zhang, Shu-Yu,Nack, William A.,Li, Qiong,Chen, Gong
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- The aza-analogues of 1,4-naphthoquinones are potent substrates and inhibitors of plasmodial thioredoxin and glutathione reductases and of human erythrocyte glutathione reductase
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Various aza-analogues of 1,4-naphthoquinone and menadione were prepared and tested as inhibitors and substrates of the plasmodial thioredoxin and glutathione reductases as well as the human glutathione reductase. The replacement of one to two carbons at the phenyl ring of the 1,4-naphthoquinone core by one to two nitrogen atoms led to an increased oxidant character of the molecules in accordance with both the redox potential values and the substrate efficiencies. Compared to the 1,4-naphthoquinone and menadione, the quinoline-5,8-dione 1 and both quinoxaline-5,8-diones 5 and 6 behaved as the most efficient subversive substrates of the three NADPH-dependent disulfide reductases tested. Modulation of these parameters was observed by alkylation of the aza-naphthoquinone core. The Royal Society of Chemistry.
- Morin, Christophe,Besset, Tatiana,Moutet, Jean-Claude,Fayolle, Martine,Brueckner, Margit,Limosin, Daniele,Becker, Katja,Davioud-Charvet, Elisabeth
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- Development of novel amino-quinoline-5,8-dione derivatives as NAD(P)H:quinone oxidoreductase 1 (NQO1) inhibitors with potent antiproliferative activities
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Fourteen novel amino-quinoline-5,8-dione derivatives (6a-h and 7a-h) were designed and synthesized by coupling different alkyl- or aryl-amino fragments at the C6- or C7-position of quinoline-5,8-dione. All target compounds showed antiproliferative potency in the low micromolar range in both drug sensitive HeLaS3 and multidrug resistant KB-vin cell lines. Compounds 6h, 6d, 7a, and 7d exhibited more potent antiproliferative effects than the other compounds. Especially, compounds 6d and 7d displayed NQO1-dependent cytotoxicity and competitive NQO1 inhibitory effects in both drug sensitive HeLaS3 and multidrug resistant KB-vin cell lines. Furthermore, compounds 6h, 6d, 7a, and 7d induced a dose-dependent lethal mitochondrial dysfunction in both drug sensitive HeLaS3 and multidrug resistant KB-vin cells by increasing intracellular reactive oxygen species (ROS) levels. Notably, compound 7d selectively inhibited cancer cells, but not non-tumor liver cell proliferation in vitro, and significantly triggered HeLaS3 cell apoptosis by regulating apoptotic proteins of Bcl-2, Bax, and cleaved caspase-3 in a dose-dependent manner. Our findings suggest that these novel C6- or C7-substituted amino-quinoline-5,8-dione derivatives, such as 7d, could be further developed in the future as potent and selective antitumor agents to potentially circumvent multi-drug resistance (MDR).
- Ling, Yong,Yang, Qiu-Xing,Teng, Yu-Ning,Chen, Shi,Gao, Wei-Jie,Guo, Jing,Hsu, Pei-Ling,Liu, Yue,Morris-Natschke, Susan L.,Hung, Chin-Chuan,Lee, Kuo-Hsiung
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- An efficient method for the synthesis of 6, 7-bis(alkylthio- or alkylamino-substituted)quinoline-5, 8-diones via nucleophilic addition/oxidation of alkylthio and alkylamino derivatives to quinoline-5, 8-dione
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A new variety of 6, 7-bis(alkylthio- or alkylamino-substituted)quinoline-5, 8-diones were prepared by the addition of mercaptans or amino nucleophiles to quinoline-5, 8-dione after subsequent oxidation with NaIO4. The core quinoline-5, 8-dione intermediate was prepared from the oxidation of 5-quinolinol or 8-quinolinol by [bis(trifluoroacetoxy)iodo]benzene, PIFA, in the presence of water and acetonitrile as solvents. No good leaving groups were utilized to insert the alkylthio or alkylamino groups into the quinoline ring. The synthesized compounds will be tested for their anti-inflammatory, anti-bacterial and tuberculostatic inhibition activities at a later stage.{figure presented}.
- Odens, Herman H.,Silva, Trevor S.,Olusola, Candace N.,Odens, Herman H.,Howe, Victoria A.,Wijatyk, Anna I.
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- Organophotocatalytic Aerobic Oxygenation of Phenols in a Visible-Light Continuous-Flow Photoreactor
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A mild photocatalytic phenol oxygenation enabled by a continuous-flow photoreactor using visible light and pressurized air is described herein. Products for wide-ranging applications, including the synthesis of vitamins, were obtained in high yields by precisely controlling principal process parameters. The reactor design permits low organophotocatalyst loadings to generate singlet oxygen. It is anticipated that the efficient aerobic phenol oxygenation to benzoquinones and p-quinols contributes to sustainable synthesis.
- Wellauer, Jo?l,Miladinov, Dragan,Buchholz, Thomas,Schütz, Jan,Stemmler, René T.,Medlock, Jonathan A.,Bonrath, Werner,Sparr, Christof
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supporting information
p. 9748 - 9752
(2021/05/27)
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- Selective Removal of Aminoquinoline Auxiliary by IBX Oxidation
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8-Aminoquinoline (AQ) is a widely used bidentate auxiliary in metal-catalyzed directed C-H functionalization reactions. Herein, we report an efficient and chemoselective method to convert various N-quinolyl carboxamides to primary amides with the treatment of a stoichiometric amount of 2-iodoxybenzoic acid oxidant or the combination of a catalytic amount of 2-iodobenzoic acid and Oxone co-oxidant in mixed solvents of H2O and HFIP. Its unique compatibility with the Phth-protected α-amino acid (αAA) substrates enhances the overall synthetic utility of the AQ-directed palladium-catalyzed C-H functionalization strategy for synthesis of complex αAAs.
- Zhang, Zhiguo,Li, Xiang,Song, Mengmeng,Wan, Yameng,Zheng, Dan,Zhang, Guisheng,Chen, Gong
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p. 12792 - 12799
(2019/07/03)
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- Quinoline quinine derivative as well as preparation method and application
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The invention discloses a quinoline quinine derivative or pharmaceutically acceptable salt, which is of a structure shown in a general formula Ia or Ib shown in the specification. By combination of structural characteristics, structure-function relationships and pharmacophore characteristics of quinoline quinine and furazan nitric acid, on the basis of a quinoline quinine structure, a furazan nitric acid NO donor is introduced; alcohol amines with different lengths are used as connection chains, so that a novel quinoline quinine derivative with NQO1 inhibition activity is designed and synthesized. Research results show that the compound disclosed by the invention has a strong inhibition effect on proliferation of various cells, and can obviously induce ROS expression of tumor cells to synergistically promote apoptosis or necrosis of the tumors.
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Paragraph 0046-0047; 0054-0055
(2020/09/20)
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- 1,2-Naphthoquinone-based Derivatives and and Methods for Preparing them
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The present invention relates to a compound represented by chemical formula (1), a pharmaceutically acceptable salt, a hydrate, a solvate, a prodrug, a tautomer, an enantiomer, or a pharmaceutically acceptable diastereomer thereof, a preparing method thereof, and a medical composition having a treating or preventing effect of metabolic diseases containing the same. Here, R_1 to R_3, and X_1 to X_6 are the same as defined in a first claim.COPYRIGHT KIPO 2015
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Paragraph 0450-0453
(2016/11/24)
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- Design, synthesis and biological evaluation of ezrin inhibitors targeting metastatic osteosarcoma
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Respiratory failure due to pulmonary metastasis is the major cause of death for patients with osteosarcoma. However, the molecular basis for metastasis of osteosarcoma is poorly understood. Recently, ezrin, a member of the ERM family of proteins, has been associated with osteosarcoma metastasis to the lungs. The small molecule NSC 668394 was identified to bind to ezrin, inhibit in vitro and in vivo cell migration, invasion, and metastatic colony survival. Reported herein are the design and synthesis of analogues of NSC 668394, and subsequent functional ezrin inhibition studies. The binding affinity was characterized by surface plasmon resonance technique. Cell migration and invasion activity was determined by electrical cell impedance methodology. Optimization of a series of heterocyclic-dione analogues led to the discovery of compounds 21k and 21m as potential novel antimetastatic agents.
- Paige, Mikell,Kosturko, George,Bulut, Güllay,Miessau, Matthew,Rahim, Said,Toretsky, Jeffrey A.,Brown, Milton L.,üren, Aykut
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p. 478 - 487
(2014/01/17)
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- 2-Phenylaminonaphthoquinones and related compounds: Synthesis, trypanocidal and cytotoxic activities
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A series of new 2-aminonaphthoquinones and related compounds were synthesized and evaluated in vitro as trypanocidal and cytotoxic agents. Some tested compounds inhibited epimastigote growth and trypomastigote viability. Several compounds showed similar or higher activity and selectivity as compared with current trypanocidal drug, nifurtimox. Compound 4l exhibit higher selectivity than nifurtimox against Trypanosoma cruzi in comparison with Vero cells. Some of the synthesized quinones were tested against cancer cells and normal fibroblasts, showing that certain chemical modifications on the naphthoquinone moiety induce and excellent increase the selectivity index of the cytotoxicity (4g and 10). The results presented here show that the anti-T. cruzi activity of 2-aminonaphthoquinones derivatives can be improved by the replacement of the benzene ring by a pyridine moiety. Interestingly, the presence of a chlorine atom at C-3 and a highly lipophilic alkyl group or aromatic ring are newly observed elements that should lead to the discovery of more selective cytotoxic and trypanocidal compounds.
- Sieveking, Ivan,Thomas, Pablo,Estevez, Juan C.,Quinones, Natalia,Cuellar, Mauricio A.,Villena, Juan,Espinosa-Bustos, Christian,Fierro, Angelica,Tapia, Ricardo A.,Maya, Juan D.,Lopez-Munoz, Rodrigo,Cassels, Bruce K.,Estevez, Ramon J.,Salas, Cristian O.
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p. 4609 - 4620
(2014/10/15)
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- Synthesis of 6-acyl-5,8-quinolinediols by photo-Friedel-Crafts acylation using sunlight
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Synthesis of acyl-5,8-quinolinediols using sunlight was investigated. Photo-Friedel-Crafts acylation of quinoline-5,8-dione and aldehyde afforded the corresponding 6-acyl-5,8-quinolinediols regioselectively in moderate to good yields. The compounds have a variety of potential applications.
- De Leon, Fernando,Kalagara, Sudhakar,Navarro, Ashley A.,Mito, Shizue
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p. 3147 - 3149
(2013/07/05)
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- The synthetic and biological studies of discorhabdins and related compounds
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Various analogues of the marine alkaloids, discorhabdins, have been synthesized. The strategy contains spirocyclization with phenyliodine(iii) bis(trifluoroacetate) (PIFA), oxidative fragmentation of the β-amino alcohols with the hypervalent iodine reagent C6F 5I(OCOCF3)2, the detosylation and dehydrogenation reaction of the pyrroloiminoquinone unit in the presence of a catalytic amount of NaN3 and the bridged ether synthesis with HBr-AcOH as the key reactions. All the synthesized compounds were evaluated by in vitro MTT assay for cytotoxic activity against the human colon cancer cell line HCT-116. Furthermore, the discorhabdin A oxa analogues were also evaluated against four kinds of tumor model cells, a human colon cancer cell line (WiDr), a human prostate cancer cell line (DU-145) and murine leukemia cell lines (P388 and L1210). For the identification of the target, discorhabdin A and the discorhabdin A oxa analogue were evaluated by an HCC panel assay. In the test, discorhabdins could have a novel mode of action with the tumor cells. The Royal Society of Chemistry 2011.
- Wada, Yasufumi,Harayama, Yu,Kamimura, Daigo,Yoshida, Masako,Shibata, Tomoyuki,Fujiwara, Kousaku,Morimoto, Koji,Fujioka, Hiromichi,Kita, Yasuyuki
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scheme or table
p. 4959 - 4976
(2011/08/06)
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- Clean catalytic oxidation of 8-hydroxyquinoline to quinoline-5,8-dione with tBuOOH in the presence of covalently bound FePcS-SiO2 catalysts
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The clean catalytic oxidation of 8-hydroxyquinoline (8-HQ) with tert-butyl hydroperoxide to quinoline-5,8-dione (QD), a molecular framework fragment of antitumor compounds, over silica-supported iron tetrasulfophthalocyanine catalysts (FePcS) is reported. The pronounced influence of the FePcS state (monomer vs. dimer) and the support (amorphous SiO2vs. mesoporous MCM-41) on the catalytic activity and selectivity is revealed. Depending on the catalyst structure, turnover frequency values determined from the initial rates of 8-HQ consumption varied from 215 to 3570 h-1.The effects of solvent, temperature, reagent concentrations and catalyst amounts on the substrate conversion and QD selectivity were studied to optimize the reaction conditions. With an optimal catalyst, the yield of the target product reached 66%. The truly heterogeneous nature of the catalysis was also demonstrated.
- Zalomaeva, Olga V.,Sorokin, Alexander B.,Kholdeeva, Oxana A.
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experimental part
p. 1076 - 1082
(2010/08/07)
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- Synthesis and biological evaluation of new cytotoxic azanaphthoquinone pyrrolo-annelated derivatives
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A series of azanaphthoquinone pyrrolo-annelated derivatives attached to basic side chains have been synthesized. The antiproliferative activities of all compounds were evaluated on at least four different cell lines. The effects on cell cycle and intercalation were investigated.
- Shanab, Karem,Schirmer, Eva,Knafl, Heike,Wulz, Eva,Holzer, Wolfgang,Spreitzer, Helmut,Schmidt, Peter,Aicher, Babette,Mueller, Gilbert,Guenther, Eckhard
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body text
p. 3950 - 3952
(2010/09/03)
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- Synthesis and anti-inflammatory structure-activity relationships of thiazine-quinoline-quinones: Inhibitors of the neutrophil respiratory burst in a model of acute gouty arthritis
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Sixteen new thiazine-quinoline-quinones have been synthesised, plus one bicyclic analogue. These compounds inhibited neutrophil superoxide production in vitro with IC50s as low 60 nM. Compounds with high in vitro anti-inflammatory activity were also tested in a mouse model of acute inflammation. The most active compounds inhibited both neutrophil infiltration and superoxide production at doses 2.5 μmol/kg, highlighting their potential for development as novel NSAIDs.
- Chia, Elizabeth W.,Pearce, A. Norrie,Berridge, Michael V.,Larsen, Lesley,Perry, Nigel B.,Sansom, Catherine E.,Godfrey, Colette A.,Hanton, Lyall R.,Lu, Guo-Liang (Leon),Walton, Michaela,Denny, William A.,Webb, Victoria L.,Copp, Brent R.,Harper, Jacquie L.
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experimental part
p. 9432 - 9442
(2009/04/11)
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- ANTI-INFLAMMATORY COMPOUNDS
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The invention relates to compounds of formula (I) or formula (II) which have anti-inflammatory activity and comprise a new class of NSAIDs. The compounds are therefore useful for treating inflammatory diseases or disorders. The invention also relates to pharmaceutical compositions containing these compounds, as well as methods of treating inflammatory diseases or disorders using compounds of formula (III) or formula (IV).
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Page/Page column 18-19
(2008/06/13)
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- Kinetics of oxidation of oxine by pyridinium dichromate
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The kinetics of oxidation of 8-hydroxyquinoline (oxine) by pyridinium dichromate has been studied in 60% acetic acid-water (v/v) medium. The reaction order is one with respect to oxidant, second with respect to the substrate and zero with respect to hydrogen ion concentration. Decrease of the dielectric constant of the medium, reduces the rate of the reaction. Increase in ionic strength has no effect on the reaction rate. The reaction does not induce the polymerization of acrylonitrile. From the kinetic data obtained, the activation parameters have been calculated and a plausible mechanism has been proposed.
- Palaniappan,Bharathi,Sekar
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p. 122 - 126
(2007/10/03)
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- Electron Transfer and Ion Pairing, 18 ; Radical Anions and Radical Ion Pairs of Aza-Substituted Naphtho- and Anthraquinones
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The redox behaviour of aza-substituted naphtho- and anthraquinones, which offer O=C-C=N- chelate tongs for an advantageous five-membered ring metal cation complexation, is investigated by a combination of cyclovoltametric and ESR/ENDOR spectroscopic measurements.The formation of paramagnetic contact ion pairs like .-Me+>., with Me+ = Li+, Na+, Tl+, or of triple ion radical cations like -Me2+>.+ with Me+ = Li+, Na+ is corroborated both by shifts of the second reduction potential of up to 0.67 V for e.g. quinoline 5,8-quinone upon additon of Li+- to its DMF solution and by the observation of ESR/ENDOR metal cuplings.
- Bock, H.,Dickmann, P.,Herrmann, H.-F.
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p. 326 - 338
(2007/10/02)
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- Substituted quinolinediones
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This disclosure describes novel 6-(4-substituted-1-piperazinyl)-5,8-quinolinediones, 7-(4-substituted-1-piperazinyl)-5,8-quinolinediones, and 6-(4-substituted-1-piperazinyl)-5,8-quinoxalinediones which possess activity an anti-asthmatic and anti-allergic agents.
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- Quinoline quinones and anti-asthmatic use thereof
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This invention relates to a class of quinoline quinones, which are useful for the therapy of immediate hypersensitivity reactions, such as asthma, and in treating any condition characterized by excessive release of leukotrienes. This invention also includes a method for treating these conditions, which comprises administering to animals, including humans, an effective dose of the quinoline quinone compounds. A further part of this invention is pharmaceutical formulations containing these pharmacologically-active compounds.
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- Nucleophilic Alkenes. IX Addition of 1,1-Dimethoxyethene to Azanaphthoquinones: Synthesis of Bostrycoidin and 8-O-Methylbostrycoidin
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Reaction of 1,1-dimethoxyethene with azanaphthoquinones leads to pairs of isomeric dimethoxyazaanthraquinones by means of 1:2-addition.A photochemical procedure has been developed for substituting these dimethoxy products by a further methoxy, amino or a hydroxy group peri to carbonyl.In this way the antibiotic bostrycoidin (1) and its 8-O-methyl derivative (2), the only natural 2-azaanthraquinone, have been synthesized for the first time.
- Cameron, Donald W.,Deutscher, Kenneth R.,Feutrill, Geoffrey I.
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p. 1439 - 1450
(2007/10/02)
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