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Dementia 2016
September 29-October 01, 2016
Volume 6 Issue 5(Suppl) J Alzheimers Dis Parkinsonism 2016
ISSN:2161-0460 JADP, an open access journal
conferenceseries .com
September 29-October 01, 2016 London, UK
5th International Conference on
Alzheimer’s Disease & Dementia
David G Churchill, J Alzheimers Dis Parkinsonism 2016, 6:5(Suppl)
Chalcogen-richorganic molecular probes for intended neurodegenerative disease purposes
David G Churchill
KAIST, Republic of Korea
In the pursuit of advances in neurodegenerative disease research, our laboratory is currently working on chemical synthesis
along three directions: protein phosphorylation and phosphate/phosphonylation detection, aromatic organoselenium-based
chemistry, andMRI contrast agent technologies are all active areas in our chemical laboratory. In our organoseleniumwork, we
are interested in making next-generation small molecular probes for the detection of reactive oxygen species. We are pursuing
reversibility, as well as improved selectivity and sensitivity. This is undertaken in the context of also studying biothiols. Sulfur,
selenium, or tellurium canbe placed within a ring, and within a π-delocalized manifold for chemical oxidation, or also as a
substituent on the aromatic ring. This oxidation, as observed previously byM. Detty et al. (1990), imparts a significant electronic
effect on the π-delocalized system and is enough to dramatically alter photophysical properties (“turn-on” fluorescence). The
chemical oxidation of an “in-ring” selenium or tellurium also brings with it a possible concomitant sterical contribution that
is also important. We have taken to functionalizing BODIPY systems–an extension of research from seeking new corrole
chemistry. Recently, we have opened up to using other fluorophores; two general design parameters that are often exploited are
(i) the aryl rotational group and (ii) the donor-acceptor photoinduced electron transfer (PET) mechanism. Based on previous
results, we saw that profound differences can be imparted by substituting a thiophene for a phenyl group. Further, substituting
Se in place of S, or adding gearing groups help alter the PET mechanism–a strategy that can be combined with chalcogen
chemical oxidation/reduction. We often conduct many interference studies and cuvette assays, but also consider the probe
when taken up into living cells, especially those of relevance to neurological diseases. Also, some of our work has ties with
Fenton chemistry. New π-delocalized skeletons that we discover can be further exploited within the topic of molecular sensing.
As always, synthesis is central to our work and emergent utility of these materials is being pursued.