Alenka Žabjek,¹ Jorge R. Barrio² and Andrej Petrič^1,*

¹ Faculty of Chemistry and Chemical Technology, University of Ljubljana, Aškerčeva 5, 1000 Ljubljana, Slovenia
² David Geffen School of Medicine at UCLA, Los Angeles, CA, USA

* Corresponding author: E-mail: andrej.petric@fkkt.uni-lj.si

Abstract
The parent DDNP molecule was modified in such a manner that an aromatic or heteroaromatic ring was attached through an ethylidene tether. A series of analogs of FDDNP, a molecular probe for protein aggregate deposition in the central nervous system, was obtained. These analogs exhibit similar optical properties as DDNP/FDDNP and thus fulfill the optical requirements for successful application in fluorescence microscopy. The introduced aromatic ring offers an additional opportunity for π-interaction between the molecule and protein aggregates.

Keywords: DDNP, fluorescent probes, synthesis, fluorescence