Observations on Some Alkyl Substituted Anthracenes and Anthraquinones

Crawford, Robert J.; Levine, Sidney; Elofson, R. M.; Sandin, Reuben B.

doi:10.1021/ja01569a044

Cited by 4 publications

(3 citation statements)

References 1 publication

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“…Va ues are reported for 39 substituted anthraquinones and three helianthranones (I) in glacial acetic acid containing 10% sulfuric acid (402). A similar study in 50% isopropyl alcohol of seven substituted anthraquinones was carried out to find a reason for the stability of 9,10-dihydro derivatives of 1,2-dimethylanthracene (77). O solid electrodes is used mainly for testing the behavior of new electrodes.…”

Section: Systemsmentioning

confidence: 99%

Organic Polarography

Wawzonek¹

1958

Anal. Chem.

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Section: Systemsmentioning

confidence: 99%

Organic Polarography

Wawzonek¹

1958

Anal. Chem.

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“…6-Mercaptopurine and melphalan were used as internal standards in the test. Test drugs were homogenized in 1 % carboxymethylcellulose and administered ip at 20 (mg/kg)/day for 9 days. After 10 days, the inoculated mice were sacrificed, and the ascitic fluid was collected.…”

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confidence: 99%

Synthesis and mutagenicity of A-ring reduced analogs of 7,12-dimethylbenz[a]anthracene

Inbasekaran¹,

Witiak²,

Barone³

et al. 1980

J. Med. Chem.

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The synthesis and mutagenicity of two derivatives of 7,12-dimethylbenz[a]anthracene (DMBA; 1), i.e., 1,2-H2DMBA (4) and 1,2,3,4-H4DMBA (5), are reported. These analogues (4 and 5) represent dihydro and tetrahydro A-ring reduced forms of DMBA, a region in the parent hydrocarbon (1) proposed to be involved in metabolism to the ultimate carcinogen. The synthesis for 4 without isolation of intermediates from the tosylhydrazone of 1,2,3,4-tetrahydrobenz[a]anthracene-4,7,12-trione (10) by successive reaction with 8 molar equiv of CH3Li, HI, and NaBH4 represents a novel approach to this hydrocarbon now available in sufficient quantity for biological studies. Interestingly, both of these reduced analogues 4 and 5 exhibited mutagenic activity in the Ames assay in the presence or absence of microsomal activation for strains TA98 and TA100. In these strains, DMBA was active only in the presence of S-9 fraction. In the plasmid-deficient strain TA1537, only tetrahydro analogue 5 exhibited mutagenic activity both in the absence and presence of S-9 fraction.

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“…In a polarographic study of substituted 9,lO-anthraquinones, Cra~vford et al (1) showed that substitution of a illethyl group for a P proton produced little change in the polarographic reduction potential. However, substitution of a methyl group for an a: proton caused a considerable increase in the polarographic reduction potential or decrease in the oxidation potential.…”

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confidence: 99%

The Electron-Spin Resonance Spectra of Some Methylated Anthrasemiquinones: Evidence for Restricted Rotation

Elofson¹,

Schulz²,

Galbraith³

et al. 1965

Can. J. Chem.

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The hyperfine electron-spin resonance spectra of a number of methyl-substituted 9,10-anthrasen~iquinones have been determined. The spectra have been analyzed by computer techniques, and splitting constants have been assigned for all protons. T h e results indicate that, while the parent quinones are essentially free of steric hindrance, the methyl groups in the cr position of the reduced quinones are not free to rotate. T h e methyl groups in t h e (3 position of the semiquinones show nor~nal hyperconjugative behavior. These results are consistent with the different redox potentials of these compounds revealed in a previous study.In a polarographic study of substituted 9, Cra~vford et al. (1) showed that substitution of a illethyl group for a P proton produced little change in the polarographic reduction potential. However, substitution of a methyl group for an a: proton caused a considerable increase in the polarographic reduction potential or decrease in the oxidation potential. This was shown to be due to steric factors by judicious choice of suitably substituted anthraquinones. In particular, the steric factor was assuilled t o operate by causing a resistance to planarity in the reduced quinone compared with the quinone itself, which must be some\vhat nonplanar (2). Gill and Stonehill (3) suggested that steric hindrance pushed both the =O and large a! substituents out of the ring plane.In this work a n attenlpt is made to investigate the hyperconjugation" (4) and restricted rotation by means of the electron-spin resonance (e.s.r.) hyperfine splitting constants of methylated anthrasemiquinones (5). The results are compared with preliminary observations on the nuclear magnetic resonance (n.n~.r.) and infrared spectra of the corresponding quinones. E X P E R I M E N T A LThe quiriones used in this investigation, except those described below, were provided through the kindness of Dr. R. J. Crawford of the University of Alberta. They were prepared by known procedures and purified by careful recrystallization from isopropyl alcohol. T h e observed melting points were anthraquinone. 286-288"; 1-inethylanthraquinone, 172-173'; 2-methylanthraquinone, 175-177"; 1,2-dimethylanthraquinone, 159-161"; 1,3-dimethylanthraquinone, 163-165"; 2,6-diinethylanthraquinone, 245-247"; 2,7-dimethylanthraquinone, 171-173"; and 1,4-dimethylanthraquinone, 151-142". 2-CD3-Anthraquino~zeToluene-CD3, RiIerclc, was allowed to react with phthalic anhydride in the presence of aluminium chloride. The resulting 4-CDj-benzoylbenzoic acid was cyclized by treating it with fuming sulfuric acid. T h e resulting 2-CD3-anthraquinone had a melting point of 172-174 "C, and no stretching vibration in the infrared caused by aliphatic CH bonds. 1-CD3-A ~tthraqz~inoneToluene-CDa, AiIerck, was brominated in the presence of nitric acid (6). The product contained both oand p-bromotoluene-CD3 which were separated by preparative gas chron~atography using a Wilken's Aerograph model 600 gas chromatograph with benzoquinoline on firebrick packing. o-Bromotoluen...

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Observations on Some Alkyl Substituted Anthracenes and Anthraquinones

Cited by 4 publications

References 1 publication

Organic Polarography

Organic Polarography

Synthesis and mutagenicity of A-ring reduced analogs of 7,12-dimethylbenz[a]anthracene

The Electron-Spin Resonance Spectra of Some Methylated Anthrasemiquinones: Evidence for Restricted Rotation

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