UV and IR spectra of anthraquinone and chrysophanol derivatives

Chumbalov, T. K.; Chanysheva, I. S.; Muzychkina, Raissa A.

doi:10.1007/bf00606188

Cited by 3 publications

(3 citation statements)

References 2 publications

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“…They also reported the formation of 1,4-anthraquinone, 9,10-anthraquinone and 9-anthrone. Anthraquinones contain two C=O bonds, which typically absorb at a frequency of 1676 cm −1 (Chumbalov et al 1967). This band position is outside of our ROI and detection is hampered by the strong H 2 O bending mode.…”

Section: Anthracene:h 2 O Photoproductsmentioning

confidence: 90%

Photochemistry of polycyclic aromatic hydrocarbons in cosmic water ice

Bouwman

Mattioda

Linnartz

et al. 2010

A&A

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Context. Polycyclic aromatic hydrocarbons (PAHs) are known to be abundantly present in photon-dominated regions (PDRs), as evidenced by their ubiquitous mid-IR emission bands. Towards dense clouds, however, their IR emission bands are strongly suppressed. It is here where molecules are known to reside on very cold grains (T ≤ 30 K) in the form of interstellar ices. Therefore, it is likely that non-volatile species, such as PAHs, also freeze out on grains. Such icy grains act as catalytic sites and, upon vacuum ultraviolet (VUV) irradiation, chemical reactions are initiated. In the study presented here, these reactions and the resulting photoproducts are investigated for PAH containing water ices. Aims. The aim of this work is to monitor vacuum ultraviolet induced chemical reactions of PAHs in cosmic ice through their IR signatures, to characterize the families of species formed in these reactions, and to apply the results to astronomical observations. Methods. Mid-infrared Fourier transform absorption spectroscopic measurements ranging from 6500 to 450 cm −1 are performed on freshly deposited and vacuum ultraviolet processed PAH containing cosmic H 2 O ices at low temperatures. Results. The mid-IR spectroscopy of anthracene, pyrene and benzo[ghi]perylene containing H 2 O ice is reported. Band strengths of the neutral PAH modes in H 2 O ice are derived. Additionally, spectra of vacuum ultraviolet processed PAH containing H 2 O ices are presented. These spectra are compared to spectra measured in VUV processed PAH:argon matrix isolation studies. It is concluded that the parent PAH species is ionized in H 2 O ice and that other photoproducts, mainly more complex PAH derivatives, also form. The importance of PAHs and their PAH:H 2 O photoproducts in astronomical mid-infrared spectroscopic studies, in particular in the 5−8 μm region, is discussed. As a test-case, the VUV photolyzed PAH:H 2 O laboratory spectra are compared to a high resolution ISO-SWS spectrum of the high-mass embedded protostar W33A and to a Spitzer spectrum of the low-mass Young Stellar Object (YSO) RNO 91. For these objects, an upper limit of 2-3% with respect to H 2 O ice is derived for the contribution of PAHs and PAH:H 2 O photoproducts to the absorbance in the 5−8 μm region towards these objects.

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Section: Anthracene:h 2 O Photoproductsmentioning

confidence: 90%

Photochemistry of polycyclic aromatic hydrocarbons in cosmic water ice

Bouwman

Mattioda

Linnartz

et al. 2010

A&A

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“…Também foram observadas duas absorções em (ν 1630 e 1676 cm −1 ), que de acordo com a literatura estão relacionadas ao grupo carbonila envolvido e não envolvido em ligação de hidrogênio, respectivamente, de uma antraquinona (CHUMBALOV, CHANYSHEVA, MUZYCHKINA, 1967;TIWARI, SINGH, 1977). O espectro de RMN de 1 H de I (Figura 71; Tabela 16) apresentou, na região dos sinais referentes aos hidrogênios aromáticos, dois dupletos em δ 7,11 (1H, J = 1,0 Hz, H-2) e 7,66 (1H, J = 1,0 Hz, H-4), característico de um sistema aromático 1,2,3,5-tetrassubstituído.…”

Section: -Elucidação Estrutural Das Substâncias Isoladas Das Flores Deunclassified

“…A análise do espectro de RMN de 13 C (Figura 89; Tabela 18), permitiu observar a presença de um sinal adicional em δ 56,2 (C-15), que foi correlacionado a metoxila. Os dados de RMN (Tabelas 18 e 19; Figuras 88−4), aliados aos dados de EM, IV, UV-Vis e CG-EM, foram similares àqueles encontrados na literatura (CHUMBALOV, CHANYSHEVA, MUZYCHKINA, 1967;DIAZ, 1990;JIN et al, 2007;MARKOVIĆ, MANOJLOVIĆ, ZLATANOVIĆ, 2008;MESELHY, 2003;TIWARI, SINGH, 1977;WANG, FENG, 2009) e são consistentes com a estrutura da 1,8-diidroxi-6-metil-3-metoxiantraquinona (II), também conhecida como fisciona. (DEMARQUE et al, 2016;JIN et al, 2007;SONG et al, 2008;WANG, FENG, 2009;YE et al, 2007), no entanto não foi possível estabelecer um mecanismo condizente para justificar este íon.…”

Section: −28 Uunclassified

Perfil metabolômico e avaliação biológica de espécies de Senna e Cassia

Nascimento¹

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Inclui bibliografia. Inclui ilustrações. Ficha Catalográfica Online do Sistema de Bibliotecas da UFU com dados informados pelo(a) próprio(a) autor(a). Bibliotecários responsáveis pela estrutura de acordo com o AACR2: Gizele Cristine Nunes do Couto -CRB6/2091 AGRADECIMENTOS Ao Prof. Dr. Marcos Pivatto pela orientação, apoio e confiança. Obrigada pelo tempo dedicado na realização deste trabalho e pelos ensinamentos transmitidos.

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