Naphthoquinones of the Vitamin K<sub>1</sub> Type of Structure

Fieser, Louis; Campbell, William P.; Fry, Edward M.; Gates, Marshall

doi:10.1021/ja01266a068

Cited by 72 publications

(16 citation statements)

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“…2-Methyl-1,4-naphthohydroquinone 2 2-methyl-1,4-naphthohydroquinone 2 was prepared from commercially available 2-methyl-1,4-naphthoquinone 1 according to literature procedure (Fieser et al 1939). …”

Section: Methodsmentioning

confidence: 99%

Simple menaquinones reduce carbon tetrachloride and iron (III)

Boonchayaanant

Tang

et al. 2008

Biodegradation

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Cell-free supernatant from Shewanella oneidensis MR-1 reduced carbon tetrachloride to chloroform, a suspension of Fe(III) and solid Fe(III) to iron (II). The putative reducing agent was tentatively identified as menaquinone-1 (MQ-1)-a water-soluble menaquinone with a single isoprenoid residue in the side chain. Synthetic MQ-1 reduced carbon tetrachloride to chloroform and amorphous iron (III) hydroxide to iron (II). To test the generality of this result among menaquinones, the reductive activities of vitamin K(2) (MQ-7)-a lipid-associated menaquinone with 7 or 8 isoprenoid residues-was evaluated. This molecule also reduced carbon tetrachloride to chloroform and iron (III) to iron (II). The results indicate that molecules within the menaquinone family may contribute to both the extracellular and cell-associated reduction of carbon tetrachloride and iron (III).

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Section: Methodsmentioning

confidence: 99%

Simple menaquinones reduce carbon tetrachloride and iron (III)

Boonchayaanant

Tang

et al. 2008

Biodegradation

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“…31 Oxidation of compound 8b with H 2 O 2 in the presence of Na 2 CO 3 gave paramagnetic menadione epoxide 9. 32 Reduction of compound 8b with Fe/AcOH 33 resulted in the removal of oxygen from nitroxide moiety without reduction of quinone to hydroquinone to afford 10. Further Diels-Alder reaction of diene 1 with 8a followed by oxidation with activated MnO 2 and DDQ yielded 1,1,3,3,7,7,9,9-octamethyl-1,3,7,9-tetrahydro-2H,8H-anthra[2,3-c:6,7-c']dipyrrol-5,11-dione-2,8-bisyloxyl biradical (11) (Scheme 2).…”

Section: Methodsmentioning

confidence: 99%

Synthesis of Pyrroline Nitroxide Annulated Carbocycles and Heterocycles

Kálai¹,

Jekő

Hideg³

2000

Synthesis

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“…i.HV. sublimiert oder nach den in der Literatur angegebenen Verfahren synthetisiert (2,3-Dimethyl-1,4-benzochinon (15c) [32], 2,6-Dimethoxy-1,4-benzochinon (150 [33], 2,3,5-Tnmethyl-l,Cbenzochinon (15d) [34], 2,3-Dimethyl-1,4-naphthochinon (5 c) [35]). …”

Section: Experimenteller Teilunclassified

Spirocyclische 3‐Oxazoline durch 1,3‐dipolare Cycloaddition von Benzonitrilio‐2‐propanid mit 1,4‐Chinonen

Stegmann

Uebelhart

Heimgartner

1983

Helvetica Chimica Acta

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On irradiation with light of wavelength 290-350 nm, 2,2-dimethyl-3-phenyl-2 H-azirine (lb) reacts with 1,4-naphthoquinone to give the 1H-benzo Iflisoindol-4,9-dione (11) (Scheme 3) via cycloaddition of the benzonitrilio-2-propanide (2 b) onto the quinone C, C-double bond. With 2-methyl-and 2,3-dimethyI-l, 4-naphthoquinone, the nitrile ylide 2 b undergoes cycloaddition preferentially onto the C, 0-double bond of the quinone, leading to spiro-oxazolines 12 and 14 (Scheme 4 ) . Steric as well as electronic effects can be discussed to explain the observed site selectivity of the cycloaddition.With the 1,4-benzoquinones 15a, 15b, 15d and 15f, nitrile ylide 2b undergoes the 1,3-dipoIar cycloaddition exclusively onto the C, 0-double bond. The corresponding spiro-oxazolines have been isolated in 17-32% yield. This contrasts with the previously reported results with benzonitrilio-phenylmethanide (2 a), which undergoes cycloaddition to the C, C-double bond of 1,4-benzoquinones (cf. [ 11). This difference in the site selectivity of the 1,3-dipolar cycloaddition can be explained with Houk's concept of LUMO-polarization, that is, the stronger nucleophilic dipol2 b polarizes the LUMO of a a,P-unsaturated carbonyl compound more efficient than the less nucleophilic 2 a.This leads to a preference of the cycloaddition to the C,O-double bond in the case of 2b.With 2,3-dimethyI-(15c) and 2,3,5,6-tetramethyl-l, 4-benzoquinone (15e), nitrile ylide 2 b undergoes C, 0as well as C, C-cycloaddition (Schemes 7 and 8 ) .1. Einleitung. -Vor einiger Zeit haben wir uber photochemisch induzierte Cycloadditionen von 2,3-Diphenyl-2H-azirin (la) mit 1,4-Chinonen berichtet [ 11. Bei dieser Reaktion werden durch 1,3-dipolare Cycloadditionen des bei der Photolyse von l a ') *) Vorgetragen von H. H. an der Euchem-

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Naphthoquinones of the Vitamin K₁ Type of Structure

Cited by 72 publications

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Simple menaquinones reduce carbon tetrachloride and iron (III)

Simple menaquinones reduce carbon tetrachloride and iron (III)

Synthesis of Pyrroline Nitroxide Annulated Carbocycles and Heterocycles

Spirocyclische 3‐Oxazoline durch 1,3‐dipolare Cycloaddition von Benzonitrilio‐2‐propanid mit 1,4‐Chinonen

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Naphthoquinones of the Vitamin K1 Type of Structure

Cited by 72 publications

References 0 publications

Simple menaquinones reduce carbon tetrachloride and iron (III)

Simple menaquinones reduce carbon tetrachloride and iron (III)

Synthesis of Pyrroline Nitroxide Annulated Carbocycles and Heterocycles

Spirocyclische 3‐Oxazoline durch 1,3‐dipolare Cycloaddition von Benzonitrilio‐2‐propanid mit 1,4‐Chinonen

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Naphthoquinones of the Vitamin K₁ Type of Structure