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A mononuclear complex Cu(L1)2·CH3OH·H2O (L1: 3,5-dibromo-L-tyrosine) was synthesized and characterized by IR, elemental analysis, and X-ray diffraction single-crystal analysis. Each Cu2+ ion is four-coordinated by two nitrogen atoms and two (carboxylic) oxygen atoms L1. Theoretical calculation of the title complex was performed by density functional theory (DFT) B3LYP method using the 6-3 l + G* basis set. Additionally, the interaction between calf thymus DNA(CT-DNA) and the complex was investigated by electrochemical methods and UV absorption spectra. And the supercoiled plasmid DNA pBR322 cleavage by the complex was investigated. The complex shows significant activity to bind to DNA and cleavage DNA. [ABSTRACT FROM AUTHOR]

In the present work, a novel 5-methyl-thiophene-carbaldehyde-functionalized rhodamine 6G Schiff base (RA) was designed and easily prepared as an Al3+ fluorescent and colorimetric probe, which could selectively and sensitively detect Al3+ by showing enhanced fluorescence emission. Meanwhile distinct color variation from colorless to pink also provided 'naked eye' detection of Al3+, due to the ring spirolactam opening of the rhodamine derivative. Other metal ions (including K+, Mg2+, Na+, Ba2+, Mn2+, Cd2+, Fe2+, Ni2+, Pb2+, Zn2+, Hg2+, Co2+, Li+, Sr2+ and Cu2+) could only induce limited interference. The detection limit of the fluorescent probe was estimated to be 4.17 × 10−6 M, the binding constant of the RA-Al3+ complex was 1.4 × 106 M−1. Moreover, this fluorescent probe RA possessed high reversibility. As aluminum is a ubiquitous metal in nature and plays vital roles in many biological processes, this chemosensor could be explored for biological study applications. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The contributions of the amino and imino resonance forms to the ground-state structures of 2-amino-4-methylpyridinium nitrate, C6H9N2+·NO3−, and the previously reported 2-amino-5-methylpyridinium nitrate [Yan, Fan, Bi, Zuo & Zhang (2012). Acta Cryst. E 68, o2084], were studied using a combination of IR spectroscopy, X-ray crystallography and density functional theory (DFT). The results show that the structures of 2-amino-4-methylpyridine and 2-amino-5-methylpyridine obtained upon protonation are best described as existing largely in the imino resonance forms. [ABSTRACT FROM AUTHOR]

In the present work, a novel 5-methyl-thiophene-carbaldehyde-functionalized rhodamine 6G Schiff base (RA) was designed and easily prepared as an Al(3+) fluorescent and colorimetric probe, which could selectively and sensitively detect Al(3+) by showing enhanced fluorescence emission. Meanwhile distinct color variation from colorless to pink also provided 'naked eye' detection of Al(3+), due to the ring spirolactam opening of the rhodamine derivative. Other metal ions (including K(+), Mg(2+), Na(+), Ba(2+), Mn(2+), Cd(2+), Fe(2+), Ni(2+), Pb(2+), Zn(2+), Hg(2+), Co(2+), Li(+), Sr(2+) and Cu(2+)) could only induce limited interference. The detection limit of the fluorescent probe was estimated to be 4.17 × 10(-6) M, the binding constant of the RA-Al(3+) complex was 1.4 × 10(6)  M(-1). Moreover, this fluorescent probe RA possessed high reversibility. As aluminum is a ubiquitous metal in nature and plays vital roles in many biological processes, this chemosensor could be explored for biological study applications., (Copyright © 2015 John Wiley & Sons, Ltd.)

In the title compound, C(15)H(12)N(2)O(2), the dihedral angle between the two benzene rings is 83.55 (11)° In the crystal, the molecules are linked by O-H⋯O and N-H⋯O hydrogen bonds.

The natural bentonite was purified and changed to sodium form by NaCl via exchange reaction. Their characteristics, such as swelling volume, swelling value, colloid valence, ethylene blue adsorbed and cation exchange capacity, were measured. The results indicate that the property of Na-bentonite is better than that of natural bentonite. Using cetyltrimethylammonium bromide (CTMAB) and homopolymer of dimethyldiallyammomium chloride (PDMDAAC) as organo-intercalating reagents, two organic modified bentonites were prepared and characterized by Fourier transform infrared (FTIR), X-ray powder diffraction (XRD) and BET surface area. The XRD results showed that the CTMAB-bentonite and PDMDAAC-bentonite had typical X-ray diffraction peaks, and the d001 values increased to 1.89 and 1.45 nm, respectively. Combined with the results of FTIR, the modified reagents had been intercalated to the layer of bentonite. The BET areas, pore volumes and average pore diameters of the two organo-bentonites were decreased as compared to that of Na-bentonite.