A novel imidazolium-functionalized BINOL fluorescent receptor R-1 was developed as a multifunctional receptor for both chromogenic and chiral anion recognition. The different fluorescent responses and color changes of R-1 could be applied to the detection of fluoride and acetate ions by the naked eye. Furthermore, the chiral recognition of the two enantiomers of alpha-amino carboxylates was also studied, and R-1 displayed a remarkable binding ability for the t-Boc alanine anion with an interesting enantioselectivity (K(L)/K(D) = 4.5).

Two anthracene derivatives appended on cyclen (1,4,7,10-tetraazacyclododecane) moieties were synthesized and characterized. In these new compounds, the anthryl is used as a substitute for the nucleobases of classical PNA backbone, and the cyclen moiety appends on the terminal amino group. The interaction of the compounds with DNA was systematically investigated by absorption, fluorescence, and viscometric titration, DNA melting and gel electrophoresis experiments. From the absorption titration data, bis-anthryl compound can bind to CT DNA with K(b) = 1.21 x 10(5) M(-1) that is 121 times larger than that of mono-anthryl compound (K(b) = 1.00 x 10(3) M(-1)). Through the fluorescence titration data, compound shows distinct CG-selective DNA binding activity. DNA melting and viscometric titration experiments indicate that the binding mode of is a multiple binding mode that involves groove binding and partial intercalation. Compound also shows excellent DNA photocleavage ability, which is much more efficient than the mono-anthryl compound .

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New imidazolium/benzimidazolium‐containing receptors (R)‐1–(R)‐6 were developed as multifunctional receptors for both chromogenic and chiral anion recognition through multichannel. The ?uorescence spectra of (R)‐1 showed a distinct and intense peak at 454, 474 nm with AcO− and F−, respectively, indicating that (R)‐1 can be applied to the detection of fluoride and acetate ions by naked eye. Receptor (R)‐5, containing a lipophilic dodecyl appendage at imidazolium nitrogen, exhibited larger fluorescent responses than (R)‐1. The ratio of fluorescence enhancement for (R)‐5 with AcO− (I460/I369=16) and F− (I485/I369=11) was 32‐fold and 18‐fold over (R)‐1 with AcO− (I454/I369=0.5) and F− (I474/I369=0.6), respectively. Less electron‐deficient benzimidazolium receptor (R)‐2 only gave fluorescence enhance at 555 nm for F−. Only chelation enhanced quenching (CHEQ) effect was obtained in the case of mono‐imidazolium receptor (R)‐4. Furthermore, (R)‐1 and (R)‐5 displayed a remarkable binding ability for the t‐Boc alanine anion with interesting enantioselectivity [KL/KD=4.5 for (R)‐1 and 4.1 for (R)‐5)], whereas only negligible enantioselectivity ability (KL/KD=1.1) was obtained by using C1 symmetric receptor (R)‐4.

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