Campus Units

Chemistry

Document Type

Article

Publication Version

Published Version

Publication Date

2-1995

Journal or Book Title

Journal of the American Chemical Society

Volume

117

Issue

6

First Page

1833

Last Page

1836

DOI

10.1021/ja00111a024

Abstract

The naturally occurring polycyclic quinone hypericin possesses light-induced antiviral activity against the human immunodeficiency virus (HIV) and other closely related enveloped lentiviruses such as equine infectious anemia virus (EIAV). We have previously argued that hypericin undergoes a fast proton transfer reaction in its singlet state (J. Phys. Chem. 1994, 98, 5784). We have also presented evidence that the light-induced antiviral activity of hypericin does not depend upon the formation of singlet oxygen (Bioorg. Med. Chem. Lett. 1994, 4, 1339). It is demonstrated here that steady-state illumination of a solution containing hypericin effects a pH drop. When hypericin and an indicator dye, 3-hexadecanoyl-7-hydroxycoumarin,a re both imbedded in vesicles, hypericin transfers a proton to the indicator within a time commensurate to its triplet lifetime. Proton transfer to the indicator is not observed when the indicator is protonated or when the system is oxygenated. Since hypericin is known to form triplets and to generate singlet oxygen with high efficiency, this latter result is taken to confirm triplet hypericin as a source, but not necessarily the only source, of protons

Comments

Reprinted (adapted) with permission from Journal of the American Chemical Society 117 (1995): 1833, doi:10.1021/ja00111a024. Copyright 1995 American Chemical Society.

Copyright Owner

American Chemical Society

Language

en

File Format

application/pdf

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