Melting points were determined by using a Gallenkamp heated block apparatus. All the dyes synthesizii were purified where necessary by column chromatography on Silica Gel CT(Reeve A) and eluted with toluene. Analytical thin-layer chromatography (TLC) was done on 0.25-mm plates of Kis-selgel, ff 244-t 365 (toluene/ethyl acstate/ghc&l acetic acid, 8: 2: 1). Microanalyses were performed by Butterworth Microanalytical Consultancy, Teddington, ...
