Reagents: Chemicals and solvents were of reagent grade and used without further purification unless otherwise stated. All reactions were performed under N2 atmosphere. All solvents used for photophysical evaluations were of HPLC grade. Deionized water was obtained from ULTRA UV/UF Rions Lab Water System Ultra 370 series. Chromatographic purifications were done with silica gel 60-120 mesh. TLC was performed on aluminum sheets coated with silica gel 60 F254 (Merck, Darmstadt).