4418-89-7Relevant academic research and scientific papers
Solvent effects on the absorption and emission spectra of novel (E)-4-((4-(heptyloxy)phenyl)diazenyl)benzyl (((9H-fluoren-9-yl)methoxy)carbonyl)-D-alaninate (Fmoc-al-az): Determination of dipole moment by experimental and theoretical study
Tej Varma,Agarwal, Devesh S.,Sarmah, Amrit,Joshi, Lata,Sakhuja, Rajeev,Pant, Debi D.
, p. 248 - 255 (2017)
Amino acid appended azobenzene hybrid has been synthesized (Fmoc-al-az) and its electronic absorbance and fluorescence spectra were recorded at room temperature in a series of polar and non-polar solvents. The ground state and excited state dipole moments were calculated using solvatochromic shift method. A DFT based study was also performed using- Gaussian09 program package. We have observed that the absorption spectra don't show sensitive behavior to the change in the polarity of the solvent, whereas a bathochromic shift was observed in the fluorescence spectra as we moved from non-polar to polar solvents indicating a π→π* transition. It was observed that the dipole moment in the excited state is much higher than the ground state, due to the amino acid containing hydrogen bond acceptor (O[sbnd]C[dbnd]O) and hydrogen bond donor ([sbnd]NH) in Fmoc-al-az increasing the reorientation tendency of the solvent molecule around the dye therefore enhancing the stabilization of the excited state which is attributed to the high polarity of the excited states. DFT level electronic structure calculations are also performed for a better molecular level understanding of the experimental observations. We obtained a good correlation between the theoretical studies and experimental results.
Aliphatic/aromatic spacers based azo dye dimers: Synthesis and application for optical storage devices
Yuvaraj,Mei, Gan Siew,Kulkarni, Ajaykumar D.,Mashitah,Hegde, Gurumurthy
, p. 50811 - 50818 (2014)
The photoisomerization effect of new bent-shaped azo dyes in the presence of aliphatic and aromatic spacers is reported for the first time. The synthesized compounds with n-hexane and benzene as central moieties were characterized by different spectral analytical techniques such as 1H-NMR, 13C-NMR, FTIR and UV-Vis. They revealed the photoisomerization effect in solution and on the solid cells as well. In solution, the E-Z and Z-E isomerization occurred in around 17-18 seconds and 7-13 hours, respectively. The dramatic variation in back relaxation is speculated to take place due to the nature of the spacers involved in the system. The synthesized materials are expected to be more useful in optical storage devices.
Single crystal structure determination and molecular modeling of ethyl 4-{[4-(dodecanoyloxy)phenyl]diazenyl}benzoate; various mesogenic behaviors from different lengths of alkyl chains
Lai, Long-Li,Su, Feng-Ya,Zhan, Kai-Chao,Cai, Yi-Lyang,Liu, Yi-Hung,Wang, Yu
, p. 197 - 204 (2007)
The molecular stacking and conformation of ethyl 4-{[4-(dodecanoyloxy) phenyl]diazenyl}benzoate was established on the basis of crystallographic data and further compared with those of 4-{[4-(decanoyloxy) phenyl]diazenyl}benzoate and 4-{[4-(octanoyloxy)ph
Design and synthesis of amino acid appended azo dye hybrid: Characterization, solvatochromic and quantum-chemical calculations using experimental and theoretical approach
Y, Tej Varma,Agarwal, Devesh S.,Sarmah, Amrit,Yukti,Sakhuja, Rajeev,Pant, Debi D.
, p. 1022 - 1028 (2016)
Amino acid appended azobenzene hybrid was synthesized and characterized using Spectroscopic techniques like 1H NMR, 13C NMR, FT-IR and Mass spectrometry analysis and its optical properties were investigated using UV–vis absorption and fluorescence spectroscopy in solvents of different polarity. Based on solvent refractive index and relative permittivity, by using the theory of solvatochromism, the excited-state (μe) and ground-state (μg) dipole moments was determined for (E)-4-((4-(heptyloxy)phenyl)diazenyl)benzyl((benzyloxy)carbonyl)glycinate (Gly-Azo-O7) based on the variation of Stokes shift as an effect of various solvent's. A bathochromic shift observed in absorption and emission spectra with increasing solvent polarity, which implied that the transition involved is π?→?π*. The ground state and excited state dipole moments were also calculated and compared using experimental and DFT calculations.
Synthesis of bent-shaped azobenzene liquid crystals derived from resorcinol for optical storage properties
Yuvaraj,Mashitah, Mohd Yusoff,Lutfor, Rahman
, p. 21 - 30 (2016)
The liquid crystalline and light-induced properties of resorcinol spacer based dimeric azobenzene were investigated. First, the compound was synthesized and elucidated the molecular structure by spectral analysis such as NMR, IR, and UV–VIS. polaring opti
Coupling Reagent for UV/vis Absorbing Azobenzene-Based Quantitative Analysis of the Extent of Functional Group Immobilization on Silica
Choi, Ra-Young,Lee, Chang-Hee,Jun, Chul-Ho
, p. 2972 - 2975 (2018)
A methallylsilane coupling reagent, containing both a N-hydroxysuccinimidyl(NHS)-ester group and a UV/vis absorbing azobenzene linker undergoes acid-catalyzed immobilization on silica. Analysis of the UV/vis absorption band associated with the azobenzene group in the adduct enables facile quantitative determination of the extent of loading of the NHS groups. Reaction of NHS-groups on the silica surface with amine groups of GOx and rhodamine can be employed to generate enzyme or dye-immobilized silica for quantitative analysis.
Synthesis and study of azo-dye compounds: Various molecular stackings from different polarities of the molecules
Lai, Long-Li,Su, Feng-Ya,Lin, Yu-Jen,Ho, Chia-Husan,Wang, Eshin,Hung, Chen-Hsiung,Liu, Yi-Hung,Wang, Yu
, p. 1517 - 1522 (2002)
One non-F-containing and two F-containing azo-dye compounds were prepared to investigate their molecular stackings by X-ray crystallography. Introduction of the F-atom into the aromatic moiety of azo-dye compounds leads to a variation of the charge distribution and consequently to different molecular stackings. Accordingly, the mesogenic behaviors in the solid state are different.
Mesomorphic, optical, dielectric, and electro-optic properties of azo-ester materials: Effect of lateral methyl and terminal substituents
Kamal, Salwa J.,Salleh, Noordini M.,Mahmud, H.N.M. Ekramul,Abdullah, Iskandar,Gopal, Sanjeev R.,Velayutham, Thamil Selvi,Zahid, N. Idayu
, (2021)
The effect of introducing a lateral methyl substituent and the two different alkoxy terminal groups on the mesophase behavior of three-benzene-ring molecular core of azo-ester compounds bearing 2-methylbutoxy unit on the opposite terminal side (C1–C6) were explored. Their structures were confirmed by several spectroscopic techniques (Fourier transform infrared spectroscopy, 1H and 13C nuclear magnetic resonance spectroscopy). The mesomorphic properties of these compounds were studied by differential scanning calorimetry, polarized optical microscopy, and small- and wide-angle X-ray scattering. Except for the un-substituted terminals (C1 and C4), all other derivatives are liquid crystalline, exhibiting enantiotropic nematic liquid crystal phase. The alteration of the alkoxy chain length from methoxy to butoxy at the phenyl ester terminal group (ring A) for each set of laterally-neat and laterally methyl-substituted mesogens decreases the nematic temperature range. A decrease in the mesophase temperature range is also observed when a lateral methyl substituent is incorporated into phenylazo ring of the mesogenic core (ring C). Optical study demonstrated that their absorption spectra are identical in shape due to the structural similarities of the mesogenic core. The corresponding fluorescence spectra exhibited blue-emission with the laterally methyl substituted compounds having a relatively higher fluorescence intensity compared to that of its laterally un-substituted analogues. Furthermore, the laterally methyl-substituted derivatives were subjected to the planar alignment and their dielectric and electro-optic properties were investigated. The nematic phase of the aligned samples shows antiferroelectric switching behavior with spontaneous polarization, Ps ~ 5 μC/cm2.
Docking Study, Synthesis, and Anti-Inflammatory Potential of Some New Pyridopyrimidine-Derived Compounds
Abdelgawad, Mohamed A.,Al-Sanea, Mohammad M.,Azouz, Amany A.,Bakr, Rania B.,El-Damasy, Ashraf K.,Elmowafy, Mohammed,Ghoneim, Mohammed M.,Musa, Arafa
, p. 451 - 463 (2022/02/05)
Background and Purpose: Because of gastrointestinal irritation and kidney toxicity associated with non-steroidal anti-inflammatory drugs and the cardiovascular problems of Coxibs use, developing novel anti-inflammatory agents with reduced toxicity and improved selectivity remains a major challenge. Depending on our previous work, a novel series of pyridopyrimidinones IIIa-i has been synthesized via reaction of 6-amino-2-thioxo-2,3-dihydro-1H-pyrimidin-4-one (I) and phenyldiazenyl aromatic aldehydes (IIa-i). All the new constructed compounds were fully characterized by elemental and spectral analysis. Methods: The target compounds IIIa–i were investigated for their potential towards COX inhibition, anti-inflammatory properties using carrageenan induced edema model in rat paw, and the ulcer indices of the most active members. Results: The ethyl pyridopyrmidinone-benzoates IIIf, IIIg and IIIh showed superior inhibitory activity of carrageenan induced edema to celecoxib. Furthermore, the pyridopyrimidinones IIId, IIIf, IIIg, and IIIi exerted improved COX-2 inhibitory activity (IC50 = 0.67–1.02 μM) comparing to celecoxib (IC50 = 1.11 μM). Moreover, the gastric ulcerogenic potential assay of compounds IIIf– h revealed their lower ulcerogenic liability than indomethacin with comparable effect to celecoxib. Conclusion: Virtual docking investigation of the most active candidates IIId, IIIf, IIIg and IIIi in the active site of COX-2 enzyme showed that these compounds implied interaction and binding motif similar to the cocrystallized ligand bromocelecoxib.
New wide-stability four-ring azo/ester/Schiff base liquid crystals: Synthesis, mesomorphic, photophysical, and DFT approaches
Ahmed, Hoda. A.,Ahmed, Nagwa H. S.,Hagar, Mohamed,Saad, Gamal R.
, p. 9643 - 9656 (2020/03/19)
New four-groups-based azo/ester/Schiff base liquid crystals, ((4-substitutedphenylimino)methyl)phenyl 4-[2-(4-alkoxyhenyl)diazenyl]benzoate, Ina-d, were synthesized and analyzed for their mesomorphic stability and optical activity. In these com
