Synthesis and Fluorescent Properties of 2-Arylamino-5-(3-Aryl-1-Phenyl-Pyrazol-4-Yl)-1,3,4-Thiadiazoles

A series of novel pyrazolyl-substituted 1,3,4-thiadiazole derivatives (6a-6d, 7a-7d, 8a-8d) were prepared by cyclization of the intermediate 3-aryl-l-phenyl-pyrazol-4-ylformaldehyde 4′-phenylthiosemicarbazones with 0.5 M ferric chloride solution. The structures of the new compounds were confirmed by IR, ¹H NMR and elemental analysis. Simultaneously, the compounds were detected by fluorescence spectrophotometer and had preferable fluorescence activity.