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Search for "quinolone" in Full Text gives 58 result(s) in Beilstein Journal of Organic Chemistry.

Aza-Diels–Alder reaction between N-aryl-1-oxo-1H-isoindolium ions and tert-enamides: Steric effects on reaction outcome

  • Amitabh Jha,
  • Ting-Yi Chou,
  • Zainab ALJaroudi,
  • Bobby D. Ellis and
  • T. Stanley Cameron

Beilstein J. Org. Chem. 2014, 10, 848–857, doi:10.3762/bjoc.10.81

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  • -a]isoquinolinone which has been isolated from Berberis darwinii [1][2][3]. Cryptolepine is an indolo[3,2-b]quinolone alkaloid found in west African shrub Cryptolepis sanguinolenta, a plant used in traditional medicine for the treatment of malaria [3]. This alkaloid has shown potent antiplasmodial [4
  • isoindolo[2,1-a]quinolone derivatives involves N-acyliminium ions or appropriate electron-deficient Schiff bases and subsequent [4 + 2] inverse-demand hetero-Diels–Alder cycloadditions with alkenes [11][12][13][14][15][16][17]. Vinylic systems from isoeugenol [11], cyclopentadiene [12], enones [13], vinyl
  • the N-aryl group undergo intramolecular electrophilic addition to the alkene yielding isoindolo[2,1-a]quinolines under acidic conditions [18]. Isoindolo[2,1-a]quinolone cores have also been prepared via an aldol-type intramolecular cyclization reaction of N-(2-acetylaryl)phthalimide under anhydrous
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Published 14 Apr 2014

New syntheses of 5,6- and 7,8-diaminoquinolines

  • Maroš Bella and
  • Viktor Milata

Beilstein J. Org. Chem. 2013, 9, 2669–2674, doi:10.3762/bjoc.9.302

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  • -benzoselenadiazole skeleton while the pyridine ring can be obtained by transformation of the pyridone core [15]. The synthesis of 7,8-diaminoquinoline (3) starting from selenadiazolo[3,4-h]quinolone 1 is depicted in Scheme 1. In the first step, the aromatization of the pyridone ring by chlorination with POCl3 in DMF
  • , which worked reliably on related azoloquinolones [15], was attempted. However, in the case of selenadiazolo[3,4-h]quinolone 1, only decomposition products were observed. On the other hand, chlorination with neat POCl3 at 90 °C afforded 6-chloroselenadiazoloquinoline 2 in 74% yield after
  • hydrochloride 5 with diimine 7 [18][19] proceeded smoothly at room temperature affording pyridoquinoxaline 8 in high yield (Scheme 2). The same reaction sequence (chlorination and reductive deselenation) was applied to selenadiazolo[3,4-f]quinolone 9 (Scheme 3). The treatment of selenadiazoloquinolone 9 with
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Published 27 Nov 2013

An overview of the synthetic routes to the best selling drugs containing 6-membered heterocycles

  • Marcus Baumann and
  • Ian R. Baxendale

Beilstein J. Org. Chem. 2013, 9, 2265–2319, doi:10.3762/bjoc.9.265

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  • ] and neatly introduces the required chloride substituent at the 5-position. While isolated pyridines are a vital component in numerous drugs the related quinoline/quinolone scaffolds are becoming increasingly common. One such example is nalidixic acid (1.101, in fact a naphthyridone, Figure 2
  • ). Nalidixic acid is a prototype quinolone antibiotic that has been used extensively as an effective treatment against both gram positive and gram negative bacteria. In general, quinolone antibiotics act by interfering with the enzymes DNA-gyrase and/or topoisomerase of bacteria [55]. Moxifloxacin (1.102
  • from the bacterial cell. Due to the elaborate substitution pattern of the parent quinolone ring systems these compounds are usually prepared via a linear consecutive sequence. In the case of moxifloxacin, an intramolecular base catalysed nucleophilic aromatic substitution is used to prepare the
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Published 30 Oct 2013

Synthesis and biological activities of the respiratory chain inhibitor aurachin D and new ring versus chain analogues

  • Xu-Wen Li,
  • Jennifer Herrmann,
  • Yi Zang,
  • Philippe Grellier,
  • Soizic Prado,
  • Rolf Müller and
  • Bastien Nay

Beilstein J. Org. Chem. 2013, 9, 1551–1558, doi:10.3762/bjoc.9.176

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  • Products, Helmholtz-Institute for Pharmaceutical Research Saarland (HIPS), Helmholtz Centre for Infection Research (HZI) and Pharmaceutical Biotechnology, Saarland University, Campus C2 3, 66123 Saarbrücken, Germany 10.3762/bjoc.9.176 Abstract Aurachins are myxobacterial 3-farnesyl-4(1H)-quinolone derived
  • class of compounds is characterized by a quinolone or quinoline nucleus substituted in position 3 or 4 by a farnesyl chain. In addition, aurachins can further be functionalized by biosynthetic oxidative processes [2][3][4][5]. Since then, additional members of this natural product family were discovered
  • at an IC50 around 20 ng/mL (i.e., aurachins B, C and E, whereas aurachin D was 100- to 200-fold less active) [6]. This antimalarial activity was comparable to that of endochin (5) [13][14] and 2-methyl-4(1H)-quinolone analogues as determined in the course of important structure–activity optimization
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Published 31 Jul 2013

Zanthoxoaporphines A–C: Three new larvicidal dibenzo[de,g]quinolin-7-one alkaloids from Zanthoxylum paracanthum (Rutaceae)

  • Fidelis N. Samita,
  • Louis P. Sandjo,
  • Isaiah O. Ndiege,
  • Ahmed Hassanali and
  • Wilber Lwande

Beilstein J. Org. Chem. 2013, 9, 447–452, doi:10.3762/bjoc.9.47

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  • 163.2) and C-9 (δ 114.8). Finally, the interaction between H-8 and C-7a in conjunction with the carbonyl signal revealed in the 13C NMR spectrum at δ 180.1, suggested a benzocyclohexenone scaffold. Combining the isoquinoline and the benzocyclohexenone skeletons led to the 7H-dibenzo[de,g]quinolone-7-one
  • scaffold. The above data were compared to those reported for fissiceine [18] leading to identification of 2 as 1-hydroxy-10-methoxy-7H-dibenzo[de,g]quinolone-7-one, which was assigned the trivial name zanthoxoaporphine A. Zanthoxoaporphine B (3) was obtained from fractions B9 and B10 as an orange powder
  • °C). 1-Hydroxy-10-methoxy-7H-dibenzo[de,g]quinolone-7-one (2): Yellowish solid; mp 178–181 °C; IR (cm−1): 3628, 1662, 1653, 1576, 1279; UV (MeOH) λmax: 207, 264, 271, 309, 350 nm; HRMS–ESI (m/z): [M + H]+ calcd for 278.0812; found, 278.0822; EIMS m/z: 250 (100%), 207 (65%), 179 (70%). 1-Hydroxy-7H
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Published 27 Feb 2013

Flow photochemistry: Old light through new windows

  • Jonathan P. Knowles,
  • Luke D. Elliott and
  • Kevin I. Booker-Milburn

Beilstein J. Org. Chem. 2012, 8, 2025–2052, doi:10.3762/bjoc.8.229

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Published 21 Nov 2012

Molecular recognition of organic ammonium ions in solution using synthetic receptors

  • Andreas Späth and
  • Burkhard König

Beilstein J. Org. Chem. 2010, 6, No. 32, doi:10.3762/bjoc.6.32

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Published 06 Apr 2010

The Elbs and Boyland- Sims peroxydisulfate oxidations

  • E. J. Behrman

Beilstein J. Org. Chem. 2006, 2, No. 22, doi:10.1186/1860-5397-2-22

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  • Scheme 7 is a possible explanation of this situation but fails to account for reality as no detectable oxygen is observed during the reaction between peroxydisulfate and either 2-quinolone or 2-quinolone-4-carboxylic acid. [16] An alternative explanation, not strictly catalytic, is shown in Scheme 8
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Published 07 Nov 2006
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