Synthesis of some new hetarylazoindole dyes have been carried out by diazotization of 5- substituted 2-aminothiazoles in nitrosylsulphuric acid and coupling with various 2-and 1, 2- disubstituted indole derivatives. The structures of the dyes were confirmed by UV-VIS, FT-IR, and 1 H NMR spectroscopy as well as by LC-MS or MS spectrometry and elemental analyses. The solvatochromism of the dyes was evaluated with respect to the absorption ...