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2.
Chem Commun (Camb) ; 50(56): 7531-4, 2014 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-24888625

RESUMO

Detection of nerve agent-related molecules based on BODIPY-salicylaldehyde oxime conjugation was studied. Fluorescence intensity of the B-SAL-OXIME species increases in the presence of DECP, whereas it decreases in the presence of DCP and DEMP (limit of detection = 997 nM). Benzonitrile formation in the novel fluorescent B-SAL-OXIME system was elucidated using model substrates.


Assuntos
Compostos de Boro/química , Substâncias para a Guerra Química/análise , Organofosfatos/análise , Espectroscopia de Ressonância Magnética/métodos
3.
Inorg Chem ; 52(17): 10052-61, 2013 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-23944230

RESUMO

A novel reversible zinc(II) chemosensing ensemble (2·Zn(2+)) allows for selective "turn-on" fluorescence sensing of ATP and PPi in aqueous media (detection limits: 2.4 and 1.0 µM, respectively) giving selective binding patterns: ATP ∼ PPi > ADP ≫ AMP > monophosphates ≈ remaining ions tested. The conjugated hydrazone [C═N-NH-R] resists hydrolysis considerably, compared to the imine [C═N-CH2-R, pyridin-2-ylmethanamine] functionality, and generalizes to other chemosensing efforts. Prerequisite Zn(2+)·[O(phenol)N(imine)N(pyr)] binding is selective, as determined by UV-vis and NMR spectroscopy; ATP or PPi extracts Zn(2+) to regenerate the ligand-fluorophore conjugate (PPi: turn-on, 512 nm; detection limit, 1.0 µM). Crystallography, 2-D NMR spectroscopy, and DFT determinations (B3LYP/631g*) support the nature of compound 2. 2-Hydrazinyl-pyridine-salicylaldehyde conjugation is unknown, as such; a paucity of chemosensing-Zn(2+) binding reports underscores the novelty of this modifiable dual cation/anion detection platform. A combined theoretical and experimental approach reported here allows us to determine both the potential uniqueness as well as drawbacks of this novel conjugation.


Assuntos
Trifosfato de Adenosina/análise , Compostos de Boro/química , Corantes Fluorescentes/química , Hidrazonas/química , Zinco/química , Hidrólise , Ligantes , Modelos Moleculares , Polifosfatos/análise , Salicilatos/química , Espectrometria de Fluorescência/métodos
4.
Analyst ; 138(10): 2829-32, 2013 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-23571476

RESUMO

Highly specific and sensitive fluorescence detection of hypochlorite in nonbiotic pure water (rapid "turn-on", ~400 fold, λ(em) ~ 560 nm) as well as in living neuronal cell cultures (neutral pH) involves oxidation of a 2-sulfide-2-benzoic acid pendent group in a new meso-thienyl-BODIPY donor-acceptor probe.


Assuntos
Compostos de Boro/química , Esterases/metabolismo , Fluorescência , Corantes Fluorescentes/química , Ácido Hipocloroso/análise , Neuroblastoma/enzimologia , Benzenossulfonatos/química , Benzoatos/química , Sobrevivência Celular , Humanos , Microscopia de Fluorescência , Estrutura Molecular , Neuroblastoma/metabolismo , Neuroblastoma/patologia , Oxirredução , Espécies Reativas de Oxigênio/metabolismo , Células Tumorais Cultivadas
5.
Inorg Chem ; 52(4): 1991-9, 2013 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-23373465

RESUMO

Various R/Ar-functionalized tin 5,10,15-tris(pentafluorophenyl)corrolate derivatives are reported herein including the first ferrocenyltin corrolate species. The isopropyl, sec-butyl-, 2-methyl-n-butyl-, phenyl-, 2-thienyl-, and ferrocenyltin species have been prepared and characterized through (1)H, (13)C, and (119)Sn HMQC NMR spectroscopy, mass spectrometry, UV-vis and photoluminescent spectroscopy, and cyclic voltammetry studies. J(C/H-Sn) NMR spectroscopic couplings and ring-current effects (upfield shifting) were determined for the R-Sn axial hydrogen and carbon atoms. This report adds to older conceptually similar reports, by, i.e., Janson et al. (J. Am. Chem. Soc. 1969, 91, 5210) and Walker et al. (J. Am. Chem. Soc.1983, 105, 6923-6929), as discussed herein. Such NMR spectroscopic aspects are discussed for these model systems. Compound Sn-Ph bond cleavage was achieved by treatment with I(2).


Assuntos
Técnicas Eletroquímicas , Compostos Orgânicos de Estanho/química , Porfirinas/química , Estanho/química , Isótopos , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Compostos Orgânicos de Estanho/síntese química , Porfirinas/síntese química
7.
Inorg Chem ; 49(2): 502-12, 2010 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-20017519

RESUMO

We report eight new A(2)B-type (M(n+)) corrolate compounds (two structural studies) that include the oxo[5,15-bis(pentafluorophenyl)-10-R-corrolatochromium(V)] [R = 2-/3-thienyl (1a/2a), 3-thianaphthyl (3a)] species. The first examples of meso-A(2) (thienyl)- and Cr-A(2)B-corrole types are represented herein. Characterization includes cyclic voltammetry, electron paramagnetic resonance, 2D ((1)H and (13)C) NMR, and UV-vis spectroscopy, mass spectrometry, and elemental analysis. Compounds 1a-3a have enabled analyte binding capacity studies. [Cu(2+)...O=Cr(cor)] binding represents a new selective mode of corrole-based detection, whereas free-base A(2)B-corroles exhibited limited M(n+) selectivity. The 10-position substitution affects optical profiles in analyte titrations. A limited amount of PPh(3) O-atom uptake from [O=Cr(cor)] was also demonstrated.


Assuntos
Compostos de Cromo/química , Porfirinas/química , Catálise , Compostos de Cromo/síntese química , Cristalografia por Raios X , Eletroquímica , Espectroscopia de Ressonância de Spin Eletrônica , Metais/química , Modelos Moleculares , Estrutura Molecular , Porfirinas/síntese química , Espectrofotometria Ultravioleta
8.
Inorg Chem ; 48(11): 4634-6, 2009 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-19371066

RESUMO

A chiral metallocorrole complex, oxo[5-(4-bromophenyl)-10-(pentafluorophenyl)-15-(2-thianaphthyl)corrolato]chromium(V) (7), was prepared and serves as the first example of an ABC-metallocorrole; meso substituents are of different electron-withdrawing capacity. An adaptation of a multistep protocol (D. T. Gryko) was made, followed by an aerobic oxidation using Cr(CO)(6) (Z. Gross). The X-ray crystal structure reveals the two enantiomers of 7. Electron paramagnetic resonance spectroscopy (g(iso) = 1.99) and cyclic voltammetry of 7 provide comparative data to that of the A(3)[tris(pfp)cCr(V)O] complex.


Assuntos
Cromo/química , Compostos Organometálicos/síntese química , Cristalografia por Raios X , Eletrodos , Espectroscopia de Ressonância de Spin Eletrônica , Modelos Moleculares , Estrutura Molecular , Compostos Organometálicos/química
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