Development of Stimulus-Responsive Ligands for the Modulation of Copper and Iron Coordination

dc.contributor.advisor

Franz, Katherine J

dc.contributor.author

Franks, Andrew Thomas

dc.date.accessioned

2014-08-27T15:20:42Z

dc.date.available

2016-08-17T04:30:03Z

dc.date.issued

2014

dc.department

Chemistry

dc.description.abstract

The ability to manipulate the coordination chemistry of metal ions has significant ramifications for the study and treatment of metal-related health concerns, including iron overload, UV skin damage, and microbial infection among many other conditions. To address this concern, chelating agents that change their metal binding characteristics in response to external stimuli have been synthesized and characterized by several spectroscopic and chromatographic analytical methods. The primary stimuli of interest for this work are light and hydrogen peroxide.

Herein we report the previously unrecognized photochemistry of aroylhydrazone metal chelator ((E)-N′-[1-(2-hydroxyphenyl)ethyliden]isonicotinoylhydrazide) (HAPI) and its relation to HAPI metal binding properties. Based on promising initial results, a series of HAPI analogues was prepared to probe the structure-function relationships of aroylhydrazone photochemistry. These efforts elucidate the tunable nature of several aroylhydrazone photoswitching properties.

Ongoing efforts in this laboratory seek to develop compounds called prochelators that exhibit a switch from low to high metal binding affinity upon activation by a stimulus of interest. In this context, we present new strategies to install multiple desired functions into a single structure. The prochelator 2-((E)-1-(2-isonicotinoylhydrazono)ethyl)phenyl (E)-3-(2,4-dihydroxyphenyl)acrylate (PC-HAPI) is masked with a photolabile trans-cinnamic acid protecting group that releases umbelliferone, a UV-absorbing, antioxidant coumarin along with a chelating agent upon UV irradiation. In addition to the antioxidant effects of the coumarin, the released chelator (HAPI) inhibits metal-catalyzed production of damaging reactive oxygen species. Finally a peroxide-sensitive prochelator quinolin-8-yl (Z)-3-(4-hydroxy-2-((4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)benzyl)oxy)phenyl)acrylate (BCQ) has been prepared using a novel synthetic route for functionalized cis-cinnamate esters. BCQ uses a novel masking strategy to trigger a 90-fold increase in fluorescence emission, along with the release of a desired chelator, in the presence of hydrogen peroxide.

dc.identifier.uri

https://hdl.handle.net/10161/9034

dc.subject

Chemistry

dc.subject

Bioinorganic

dc.subject

chelator

dc.subject

coumarin

dc.subject

Oxidative Stress

dc.subject

photolabile

dc.title

Development of Stimulus-Responsive Ligands for the Modulation of Copper and Iron Coordination

dc.type

Dissertation

duke.embargo.months

24

Files

Original bundle

Now showing 1 - 2 of 2
Loading...
Thumbnail Image
Name:
Franks_duke_0066D_12518.pdf
Size:
6.04 MB
Format:
Adobe Portable Document Format
Loading...
Thumbnail Image
Name:
Franks_duke_0066D_17/Appendix.pdf
Size:
618.84 KB
Format:
Adobe Portable Document Format

Collections