In this paper, two compounds of s-triazine derivatives which named 2,4-dimethyl-6-[(4'-N,N-dimethylamino) phenylethenyl]-1,3,5-s-triazine (1) and 2-styryl-4,6-dimethyl-1,3,5-triazine (2) were synthesized and characterized by ¹H NMR, MS and elemental analysis. The interactions between the metal ions and compounds 1～3 were investigated by UV-vis spectroscopy. Results indicated that the absorption spectrum of compound 1 had a remarkable change when it combined with Fe³⁺ and Cu²⁺, and the maximum absorption peaks shifted from 393 nm to 525 nm and 513 nm, respectively. The models of compound 1 intergraded with Fe³⁺ and Cu²⁺ were 1∶1 and 2∶1, respectively, but with the same remarkable color change from yellow to pink by naked-eye colorimetric detection. The association constants of 1-Fe³⁺ and 1-Cu²⁺ were 1.8×10⁴ L·mol^-1 and 2.6×10¹⁰ L·mol^-1 respectively. Meanwhile, the spectrum of compound 2 underwent distinct change when it combined with Fe³⁺ and the maximum absorption peak shifted from 304 nm to 357 nm. But less change was observed when it intergraded with Cu²⁺. The ratio of compound 2 intergraded with Fe³⁺ was 1∶1 and the association constants was 1.0×10⁵ L·mol^-1. Therefore, we could concluded that Fe³⁺ combined with the ring of triazine of the compounds 1 and 2, but the Cu²⁺ intergraded with N atom of the methylamino of the compound 1. At the same time, the interactions of compounds 1 and 2 with other ions such as Li⁺, K⁺, Mg²⁺, Ca²⁺, Co³⁺, Ni²⁺, Ag⁺, Cd²⁺, Hg²⁺and Zn²⁺ were also investi gated, but obvious absorption spectral changes was not observed. Thus a new kind chemosensor for Fe³⁺ and Cu²⁺with high selectivity and sensitivity was introduced.

Key words: s-triazine derivatives, colorimetric assay, Fe³⁺, Cu²⁺