Document Detail


Chelation of hypocrellin B with zinc ions with electron paramagnetic resonance (EPR) evidence of the photodynamic activity of the resulting chelate.
MedLine Citation:
PMID:  11767412     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
Hypocrellin B (HB), a perylenequinone derivative, is an efficient phototherapeutic agent. The chelation of HB with Zinc ions (Zn2+) results in a metal chelate (Zn-HB) which exhibits considerable absorption (lambda max = 612 nm) in the phototherapeutic window. The structure of this chelate has been characterized by UV-Vis, IR and mass spectra. The redox potentials of the Zn-HB chelate were Eox = +1.1 V (vs. SCE) and Ere = -0.7 V (vs. SCE) as measured using the circle volt curve. The quantum yield of singlet oxygen generated by the Zn-HB chelate was 0.86, which both the electron spin trap (EPR) method and the chemical trap method show to be about 0.1 higher than that of its parent compound HB. In irradiated oxygen-saturated solutions of Zn-HB chelate, superoxide radical anions and hydroxyl radicals were detected by EPR spectroscopy using 5,5-dimethyl-1-pyrroline-N-oxide (DMPO) as the spin-trapping agent.
Authors:
C Tian; S Xu; S Chen; J Shen; M Zhang; T Shen
Publication Detail:
Type:  In Vitro; Journal Article; Research Support, Non-U.S. Gov't    
Journal Detail:
Title:  Free radical research     Volume:  35     ISSN:  1071-5762     ISO Abbreviation:  Free Radic. Res.     Publication Date:  2001 Nov 
Date Detail:
Created Date:  2001-12-20     Completed Date:  2002-02-21     Revised Date:  2006-11-15    
Medline Journal Info:
Nlm Unique ID:  9423872     Medline TA:  Free Radic Res     Country:  Switzerland    
Other Details:
Languages:  eng     Pagination:  543-54     Citation Subset:  IM    
Affiliation:
Center for Molecular Science, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100080, P.R. China.
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MeSH Terms
Descriptor/Qualifier:
Chelating Agents
Electrochemistry
Electron Spin Resonance Spectroscopy
Humans
Hydroxyl Radical / chemistry
Molecular Structure
Perylene / analogs & derivatives*,  chemistry*,  pharmacology*
Photochemotherapy
Photosensitizing Agents / chemistry*,  pharmacology*
Quinones / chemistry*,  pharmacology*
Spectrometry, Fluorescence
Spectrophotometry
Spectrophotometry, Infrared
Superoxides / chemistry
Zinc
Chemical
Reg. No./Substance:
0/Chelating Agents; 0/Photosensitizing Agents; 0/Quinones; 11062-77-4/Superoxides; 123940-54-5/hypocrellin B; 198-55-0/Perylene; 3352-57-6/Hydroxyl Radical; 7440-66-6/Zinc

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


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