Results 121 to 130 of about 1,037 (167)

A photophysical study of some purpurins

Journal of the Chemical Society, Faraday Transactions, 1990
Ground-state, fluorescence, triplet-state and singlet-oxygen luminescence studies are reported for two purpurins, a metallo (SnIV) purpurin and a porphyrin tautomer, NTW, containing an unsaturated meso-substituent. Fluorescence lifetimes of the purpurins are short (ca.
Alisdair N. Macpherson, David Kessel, Alan R. Morgan, Ian Munro, T. George Truscott   +4 more
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Purpurin: A natural anthraquinone with multifaceted pharmacological activities

Phytotherapy Research, 2020
Purpurin is a naturally occurring anthraquinone isolated from the roots of Rubia cordifolia. Historically, it has been used as a red dye. However, its photosensitizing property and biological effects have deciphered its novel application. Purpurin shows antigenotoxic, anticancer, neuromodulatory, and antimicrobial potential associated with antioxidant ...
Jyoti Singh, Yusuf Hussain, Suaib Luqman, Abha Meena   +3 more
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Photophysical And Photochemical Properties Of Purpurins

SPIE Proceedings, 1989
The photochemical and photophysical properties of purpurins have been investigated. Photophysical measurements indicate that these sensitizers have high quantum yields of long lived triplet excited states which efficiently quench molecular oxygen, giving rise to singlet oxygen.
Alan R. Morgan, Greta M. Garbo, T. George Truscott   +2 more
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Organotin Complexes of Alizarin and Purpurin

Zeitschrift für anorganische und allgemeine Chemie, 2008
AbstractFive novel organotin complexes with the anthraquinone dyes alizarin (1,2‐dihydroxyanthraquinone) and purpurin (1,2,4‐trihydroxyanthraquinone) were synthesized and characterized by elemental analyses, FTIR and NMR spectroscopy (1H, 13C and 119Sn).
Adriana T. de Sousa, Karl E. Bessler, Sebastia˜o S. Lemos, Javier Ellena, Claudia C. Gatto   +4 more
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Synthesis of Monosubstituted Purpurins and Their Biological Activity

Chemistry of Natural Compounds, 2019
Products were obtained from acylation of 1,2,4-trihydroxy-9,10-anthraquinone (purpurin) by saturated cyclic carboxylic acid chlorides. The compositions and structures of the monosubstituted compounds were confirmed by elemental analysis and IR and PMR spectroscopy.
T. V. Kharlamova, R. B. Seidakhmetova, K. D. Praliev   +2 more
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From purpurin-18 to new purpurin imide derivatives with functional groups

Journal of Porphyrins and Phthalocyanines
Chlorins are among the most interesting photosensitizers for photodynamic therapy because they exhibit a high quantum yield of the singlet oxygen generation and absorbance in the deep red. Indeed the penetration depth of light into skin increases with wavelength from the UV to the near-infrared light range.
Luce Janice Ndzimbou, Yves Champavier, Frédérique Brégier, Vincent Sol   +3 more
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Purpurins and benzochlorins as sensitizers for photodynamic therapy

Journal of Photochemistry and Photobiology B: Biology, 1996
Purpurins and benzochlorins are hydrophobic second generation photosensitizers, which have sizable absorption in the 650-780 nm range and exhibit photodynamic activity against tumors after visible light treatment. This review summarizes the published data regarding these compounds: from the spectroscopic, photophysical and photochemical characteristics
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Purpurins: Improved Photosensitizers For Photodynamic Therapy

SPIE Proceedings, 1988
Two new groups of photosensitizers, purpurins and metallopurpurins were tested for photodynamic activity when combined with visible light (>590nm), in the treatment of transplantable urothelial tumors (FANFT induced) in Fischer 344 rats. In preliminary studies, animals were injected with 10 mg/kg body weight (b.w.) of the free base purpurins (NT1, NT2,
Alan R. Morgan, Martha Kreimer-Birnbaum, Greta M. Garbo, Rick W. Keck, Steven H. Selman   +4 more
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Revised Relative and Absolute Stereochemistry of (+)-Purpurin

Journal of Natural Products, 1998
The relative and absolute stereochemistries of (+)-purpurin (3), a flavanone natural product from Tephrosia, were determined to be 2S,7aR,10S,10aS by synthesis from semiglabrin in conjunction with X-ray crystallographic analysis.
, Pirrung, , Lee, , Morehead, , McPhail
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Sedimentary purpurins: oxidative transformation products of chlorophylls

Organic Geochemistry, 1998
Examination of sediments from three contemporary lakes (Priest Pot, Loch Ness and Lake Baikal) reveals the presence of oxidative transformation products of chlorophyll a in two of the settings. Purpurin-18 phytyl ester, not previously reported in sediments, occurs in the two lakes that have deep water columns.
C.C. Naylor, B.J. Keely
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