Synthetic strategy Our syntetic strategy was based on our preliminary results. Bříza, T.; Kejík, Z.; Vašek, P.; Králová, J.; Martásek, P.; Císařová, I.; Král, V. Org. Lett. 2005, 17, 3661-3664 We have used derivatives of benzothiazolium iodide 2, 4 and 5, which were reacted with para-nitrophenylmalondialdehyde 6. In the first step, there was necessary to prepare the salts 2 and 4 5-hydroxy-2-methyl benzothiazole was reacted with propyl iodide under 100 °C for 3 days and corresponding iodonium

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... lt 2 was obtained in yield 84 %. In case of salt 4 at first, the hydroxybenzothiazole 1 was substituted with triethylene glycol chain by means of triethyleneglycol tosylate in presence of sodium hydride in dimethylformamide. The substitution afforded product 3 in high yield 91 %. Benzothiazole 3 was then treated with propyl iodide at 100 °C to obtain salt 4 in 68 % yield. Carefull NMR analysis confirmed the same geometry of the compound 7 in solution as well as in solit state. The analysis was based on NOE experiment. The assignment of individual hydrogens was accomplished by means of 1 H-NMR, 13 C-NMR, COSY, and NOE experiment. Assignment of hydrogens according 1 H NMR spectra. Compound 7 NO 2 N