Issue 10, 2008

Synthesis of zinc bacteriochlorophyll-d analogues with various 17-substituents and their chlorosomal self-aggregates in non-polar organic solvents

Abstract

Zinc 31-demethyl-bacteriopheophorbides-d possessing various 17-propionate residue (172-COOCH2–) were prepared as models of light-harvesting pigments in major photosynthetic antennae of green bacteria. The synthetic compounds were monomeric in polar organic solvents to give the same visible absorption spectra, but self-aggregated in non-polar organic solvents to afford large oligomers with broadened and red-shifted absorption bands. The peak positions were identical for all the self-aggregates but the widths of the redmost (Qy) bands were dependent upon the substituents. More hydrophobic and less sterically hindered hydrocarbon moieties as the esterifying group sharpened oligomeric Qy bands, giving less inhomogeneous supramolecular structures due to stabilization of the self-aggregates. In the reverse esters (172-CH2OCO–) structurally isomeric to the above compounds, the same optical behavior was observed. Movement of the oxo group from the 173- to 175-position (172-COOCH2– → 172-CH2OCO–) slightly increased the widths of self-aggregated Qy bands without change of the peak positions, where minor less self-aggregated components would enhance in the solution due to a little more stabilization of such species by the 174-carbonyl group.

Graphical abstract: Synthesis of zinc bacteriochlorophyll-d analogues with various 17-substituents and their chlorosomal self-aggregates in non-polar organic solvents

Supplementary files

Article information

Article type
Paper
Submitted
11 Feb 2008
Accepted
14 May 2008
First published
04 Jun 2008

Photochem. Photobiol. Sci., 2008,7, 1225-1230

Synthesis of zinc bacteriochlorophyll-d analogues with various 17-substituents and their chlorosomal self-aggregates in non-polar organic solvents

H. Tamiaki, T. Michitsuji and R. Shibata, Photochem. Photobiol. Sci., 2008, 7, 1225 DOI: 10.1039/B802359J

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Spotlight

Advertisements