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Three novel carbazole-thiosemicarbazides based Schiff-base were synthesized. The recognition ability of representive 2-((N-heptane-carbazol-3-yl)methylidene)hydrazine carbothioamide (L 2 ) to metal ions was investigated by naked-eye, UV-Vis, fluorescence and mass spectra. The experimental results showed that this compound had a good water solubility and can be investigated in DMSO-H 2 O (V∶V＝6∶4, Tris-HCl buffer, pH＝7.0). The compound L 2 in the DMSO-H 2 O displayed a distinct color change from colorless to yellow upon the addition of Cu 2＋ , other metal ions did not induce significant colour changes, which indicated that Schiff base L 2 can be used as a probe with naked eye detection for Cu 2＋ . The fluorescence spectra showed that the probe L 2 was a high selective and sensitive "turn-off" fluorescence probe for Cu 2＋ in DMSO-H 2 O (V∶ V＝6∶4, Tris-HCl buffer, pH＝7.0). The association constant between the probe L 2 and Cu 2＋ was detected to be 3.42×10 4 L•mol -1 , and the detection limit was calculated to be 8.96×10 -6 mol•L -1 . MS analysis showed a 1∶1 binding stoichiometry between Cu 2＋ and L 2 . The detection limit of L 2 for Cu 2＋ was far lower than the maximum allowable level of World Health Organization (WHO) limit (20 mol•L -1 ) for drinking water.

A series of new 3,6-disubstituted triazolothiadiazole derivatives 7a～7y containing benzimidazole and arylsulfonyl moities have been synthesized by o-phenylenediamine and chloroacetic acid as starting materials via multistep reactions. The structures of the intermediates 3, 4, 6 and the target compounds 7 were characterized by 1 H NMR, IR spectra and elemental analysis. All synthesized target compounds were screened for their inhibitory activity against cell division cycle 25B phosphatase (Cdc25B) and protein tyrosine phosphatase 1B (PTP1B). The results show that some of them display significant inhibitory activities against Cdc25B and PTP1B. Among them, compound 7d exhibits the highest inhibitory activity against Cdc25B [IC 50 ＝(7.72±0.73) μg/mL] and 7u exhibits the highest inhibitory activity against PTP1B [IC 50 ＝(3.31±0.57) μg/mL]. It is noteworthy that compounds 7b, 7d, 7l, 7t and 7u show higher inhibitory activities against Cdc25B and PTP1B. They can be considered as potential Cdc25B and PTP1B inhibitors, and have great application prospects in the treatment of cancers and diabetes.