Preface

Colthup, Norman B.; Daly, Lawrence H.; Wiberley, Stephen E.

doi:10.1016/b978-0-08-091740-5.50003-x

Cited by 345 publications

(555 citation statements)

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“…The former is Raman active, and the asymmetric will be IR active only, assigned for most carboxyl dimers at 1720-1680 cm -1 . 36 Such observation agrees with the absorptions observed at 1665-1682 cm -1 assigned to n as (C=O) for 1, 2 and 3. Further, the carboxyl dimer presents a characteristic infrared band at 960-875 cm -1 which corresponds to out-of-plane OH … O hydrogen deformation.…”

supporting

confidence: 81%

“…12, 2010 Compounds 1 and 2 could be analyzed as R-C(=O)OH carboxylic derivatives, usually characterized in the solid state by a strong, very broad O-H stretching near 3000 cm -1 . 36 In compounds 1 and 2 this broad band was observed at 2986 and 2985 cm -1 , respectively. In compound 3 this absorption was absent.…”

Section: Infrared Spectramentioning

confidence: 98%

“…Further, the carboxyl dimer presents a characteristic infrared band at 960-875 cm -1 which corresponds to out-of-plane OH … O hydrogen deformation. 36 In the case of 1 and 2, this characteristic absorption is observed near 850 cm -1 probably due to electronic delocalization towards the terminal aryl Strong bands observed for 1, 2 and 3 near 750 cm -1 were attributed to the C-H out-of-plane deformation and the very strong absorptions observed at 1597-1611 cm -1 were assigned to the C=C axial deformation, both characteristic of aromatic compounds. 38 …”

mentioning

confidence: 98%

“…The main absorptions and vibrational assignments were compared with literature data. [36][37][38] Amide derivatives are characterized by two absorptions in sequence with medium intensities and 120-200 cm -1 spacing in the 3550-3150 cm -1 region. In compound 3 these absorptions were assigned at 3493 and 3404 cm -1 .…”

Section: Infrared Spectramentioning

confidence: 99%

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In vitro evaluation of triazenes: DNA cleavage, antibacterial activity and cytotoxicity against acute myeloid leukemia cells

Domingues

Hörner

Reetz

et al. 2010

J. Braz. Chem. Soc.

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triazeno (3) foram avaliadas quanto à capacidade de clivagem do DNA plasmidial pUC18 e pBSKII, atividade antibacteriana e citotoxicidade in vitro frente a células de leucemia mielóide aguda e leucócitos normais utilizando o bioensaio da redução do sal brometo de 3-(4,5-dimetiltiazol-2-il)-2,5-difeniltetrazólio (MTT). Os triazenos analisados demonstraram capacidade de clivagem dos dois tipos de DNA plasmidial: triazeno 1 em pH 8,0 e 50 °C; triazeno 2 em pH 6,5 a 37 e 50 °C; triazeno 3 em pH 6,5 e 37 °C. Os compostos apresentaram atividade citotóxica frente a células leucêmicas. O composto 1 mostrou alta atividade frente a B. cereus (CIM = 32 mg mL -1 ). A associação molecular através de ligações de hidrogênio no estado sólido do composto 3 com base na análise estrutural por difratometria de raios X em monocristal, bem como os resultados das análises espectroscópicas nas regiões do IV e UV-Vis dos compostos 1, 2 e 3 são discutidos no presente trabalho.The asymmetric diazoamines 1-(2-chlorophenyl)-3-(4-carboxyphenyl)triazene (1), 1-(2-fluorophenyl)-3-(4-carboxyphenyl)triazene (2) and 1-(2-fluorophenyl)-3-(4-amidophenyl) triazene (3) were evaluated for their ability to cleave pUC18 and pBSKII plasmid DNA, antibacterial activity and in vitro cytotoxicity against acute myeloid leukemia cells and normal leukocytes using the bioassay of reduction of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT). The triazenes showed ability to cleave the two types of plasmid DNA: triazene 1 at pH 8.0 and 50 °C; triazene 2 at pH 6.5 and 37 and 50 °C; triazene 3 at pH 6.5 and 37 °C. The compounds presented cytotoxic activity against myeloid leukemia cells. Compound 1 showed high activity against B. cereus (MIC = 32 mg mL -1 ). The observation of intermolecular hydrogen bonding in the solid state of compound 3, based on the structural analysis by X-ray crystallography, as well as the results of IR and UV-Vis spectroscopic analyses of compounds 1, 2 and 3 are discussed in the present work.Keywords: triazenes, DNA cleavage, antibacterial activity, cytotoxicity IntroductionTriazenes or diazoamines constitute a class of compounds containing three consecutive nitrogen atoms in an acyclic arrangement. 1 Diazoamino compounds can be obtained by diverse synthetic ways, the classical method including the coupling reaction of a diazonium salt, [R-N≡N] + X -, with an amine (R'-NH 2 ) in acidic medium. This is followed by formation of the respective diazoamino compound R-N=N-N(H)-R' (R = R' for Domingues et al. 2227 Vol. 21, No. 12, 2010 symmetric triazenes; R ≠ R' for asymmetric compounds) by stepwise neutralization of the reaction system. They have diverse applications as DNA alkylating agents in tumor therapy, protecting groups in natural product synthesis and combinatorial chemistry, as well as precursors incorporated into polymer and oligomer synthesis. [2][3][4][5][6][7][8] Hydrolysis of DNA or RNA catalyzed by relevant enzymes is an important subject in biotechnology, medicine and drug development. 9,10 Synthetic nuclease...

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supporting

confidence: 81%

Section: Infrared Spectramentioning

confidence: 98%

mentioning

confidence: 98%

Section: Infrared Spectramentioning

confidence: 99%

See 2 more Smart Citations

In vitro evaluation of triazenes: DNA cleavage, antibacterial activity and cytotoxicity against acute myeloid leukemia cells

Domingues

Hörner

Reetz

et al. 2010

J. Braz. Chem. Soc.

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“…The spectrum revealed a new band at 1373 cm -1 attributed to C-N vibrations, and the disappearance of the band at 1310 cm -1 , corresponding to NO 2 group stretching frequencies. 19 In order to monitor this reaction we chose the following absorption bands (Figure 2): A = 1373 cm -1 , stretching of the phenyl C-N bond, and B = 1450 cm -1 , attributed to the polystyrene matrix.…”

Section: Second Step -Reduction Of Nitro Groupmentioning

confidence: 99%

An efficient monitoring technique for solid-phase reactions by KBr pellets/FT-IR using methyl p-aminobenzoate synthesis assisted by microwave radiation on merrifield resin

Antonow¹,

Graebin²,

Eifler‐Lima³

2004

J. Braz. Chem. Soc.

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O uso de pastilhas de KBr em espectroscopia de infravermelho foi investigado para a monitorização de reações em fase sólida. A síntese do p-aminobenzoato de metila na Resina Merrifield (RM) é descrita como um modelo para esta técnica, a qual permite que o progresso das três etapas da síntese sejam monitoradas.The use of KBr pellets in infrared spectroscopy has been investigated for monitoring solidphase reactions. Synthesis of the methyl p-aminobenzoate on Merrifield resin (MR) is described as a model for this technique, which allows the progress of its three on-bead reaction steps to be monitored throughout their duration.

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Characterization of polyimide Langmuir-Blodgett films on silver using infrared, Raman and x-ray photoelectron spectroscopies

Zhao¹,

Boerio²

1998

Surf. Interface Anal.

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This work investigates the problem of ???∞ estimation for uncertain continuous time non‐linear systems with non‐linear time‐varying parameter uncertainty. A non‐linear estimator is looked for so that a prescribed bound on the ratio between the energy of the estimation error and the energy of the noise inputs is achieved for any set of parameters in a prescribed bounded region. Conditions for the existence of such an estimator are not easy to find and we therefore formulate an auxiliary estimation problem for a related system which is obtained from the original one by converting the parameter uncertainty into exogenous bounded energy signals. It is shown that an ???∞ non‐linear estimator that solves the auxiliary problem, if one exists, guarantees, when applied to the original problem, the required performance for all possible parameters. This approach allows us to solve the robust non‐linear ???∞ estimation problem via recently developed ???∞ non‐linear filtering techniques. The results are demonstrated by a simple example.

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Preface

Cited by 345 publications

References 0 publications

In vitro evaluation of triazenes: DNA cleavage, antibacterial activity and cytotoxicity against acute myeloid leukemia cells

In vitro evaluation of triazenes: DNA cleavage, antibacterial activity and cytotoxicity against acute myeloid leukemia cells

An efficient monitoring technique for solid-phase reactions by KBr pellets/FT-IR using methyl p-aminobenzoate synthesis assisted by microwave radiation on merrifield resin

Characterization of polyimide Langmuir-Blodgett films on silver using infrared, Raman and x-ray photoelectron spectroscopies

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