538-41-0Relevant academic research and scientific papers
Novel Synthesis of 2-Amino-1,4-benzoquinone-4-phenylimides from Anilines via Dess-Martin Periodinane Oxidation
Ma, Heng Chang,Jiang, Xuan Zhen
, p. 1679 - 1682 (2007)
A synthetic investigation on oxidation of anilines to 2-amino-1,4-benzoquinone-4-phenylimides via Dess-Martin periodinane (DMP) was carried out. This facile protocol offered the advantage of short reaction times, mild reaction conditions, high yields and compatibility with a wide range of functional groups.
Photocontrolled reversible morphology conversion of protein nanowires mediated by an azobenzene-cored dendrimer
Sun, Hongcheng,Zhao, Linlu,Wang, Tingting,An, Guo,Fu, Shuang,Li, Xiumei,Deng, Xiaoli,Liu, Junqiu
, p. 6001 - 6004 (2016)
A novel strategy to construct photocontrolled protein nanowires with reversible morphology was reported through photoisomerizable azobenzene-cored dendrimer evoked protein self-assembly. Furthermore, the curvature of the protein nanowires could be switched by alternatively irradiating with visible light and ultraviolet light.
Interactions of 4,4′-diaminoazobenzene derivatives with telomeric G-quadruplex DNA
McCallum, Jeremy E. B.,Coyle, Christopher W.,Elson, Ryan R.,Titterington, Blake A.
, p. 169 - 178 (2018)
The development of small molecules to stabilize the G-quadruplex structure has garnered significant attention for anticancer drug discovery. Herein, we report the synthesis of several 4,4′-diaminoazobenzene derivatives containing different substituent groups and their ability to bind and stabilize telomeric G-quadruplex DNA. Circular dichroism (CD) spectroscopy was performed to characterize the quadruplex topologies, measure stabilization effects, and evaluate their capabilities for conformational photoregulation. 4,4′-Diaminoazobenzene derivatives were found to moderately stabilize quadruplex structures but not affect conformational photoregulation. This work further develops the design and general understanding of the stabilization effects of small molecules with telomeric G-quadruplex DNA.
New thermotropic symmetrical and unsymmetrical azomethine with azobenzene unit and fluorinated alkyl chain: Synthesis and characterization
Hamryszak, Lukasz,Janeczek, Henryk,Schab-Balcerzak, Ewa
, p. 12 - 20 (2012)
A new thermotropic liquid crystals containing azobenzene unit and imine linkages were synthesized via condensation of 4-(4,4,5,5,6,6,7,7,8,8,9,9,10,10, 11,11,11-heptadecafluoroundecyloxy)benzaldehyde with 4-aminoazobenzene (AzoAz-1) and 4,4′-diaminoazobenzene (AzoAz-2). The structures of compounds were characterized by means of NMR, FTIR spectroscopy and elemental analysis; the results show an agreement with the proposed structure. The mesomorphic behavior of the unsymmetrical AzoAz-1 and symmetrical AzoAz-2 azobenzeneimines was investigated via differential scanning calorimetry (DSC) and polarizing optical microscopy (POM). Based on the POM and DSC measurements AzoAz-1 exhibited smectic phases (SmX, SmA), while AzoAz-2 showed smectic (SmX1, SmX2, SmA) and nematic (N) mesophases. Optical properties of the azobenzeneimines were tested by UV-vis and photoluminescence (PL) spectroscopy in various solvents. Preliminary investigations of electrical properties of the new compounds were carried out by current-voltage (I-V) measurements performed on ITO/compound/Al device.
Conversion of anilines into azobenzenes in acetic acid with perborate and Mo(VI): correlation of reactivities
Karunakaran,Venkataramanan
, p. 375 - 385 (2019/02/14)
Azobenzenes are extensively used to dye textiles and leather and by tuning the substituent in the ring, vivid colours are obtained. Here, we report preparation of a large number of azobenzenes in good yield from commercially available anilines using sodium perborate (SPB) and catalytic amount of Na2MoO4 under mild conditions. Glacial acetic acid is the solvent of choice and the aniline to azobenzene conversion is zero, first and first orders with respect to SPB, Na2MoO4 and aniline, respectively. Based on the kinetic orders, UV–visible spectra and cyclic voltammograms, the conversion mechanism has been suggested. The reaction rates of about 50 anilines at 20–50?°C and their energy and entropy of activation conform to the isokinetic or Exner relationship and compensation effect, respectively. However, the reaction rates, deduced by the so far adopted method, fail to comply with the Hammett correlation. The specific reaction rates of molecular anilines, obtained through a modified calculation, conform to the Hammett relationship. Thus, this work presents a convenient inexpensive non-hazardous method of preparation of a larger number of azobenzenes, and shows the requirement of modification in obtaining the true reaction rates of anilines in acetic acid and the validity of Hammett relationship in the conversion process, indicating operation of a common mechanism.
PHOTOCHROMIC COMPOUNDS FOR USE IN THE TREATMENT OF EYE DISORDERS
-
Page/Page column 23, (2019/12/28)
The present patent application relates to compounds of formula (1) wherein Y and Z are independently O, N, P; R, R1, R2, R3, where present, are independently H, optionally substituted C1-C12 alkyl, O, or R and R1 and/or R2 and R3 form, together with the atom Y and/or Z to which they are attached, a 3-14 membered ring, optionally containing one or more additional heteroatoms selected from O, N, and S, optionally substituted, compositions comprising such compounds and the medical use of such compounds.
A Natural Glycyrrhizic Acid-Tailored Light-Responsive Gelator
Fang, Heshu,Zhao, Xia,Lin, Yuan,Yang, Song,Hu, Jun
, p. 1192 - 1198 (2018/04/02)
The construction of stimuli-responsive materials by using naturally occurring molecules as building blocks has received increasing attention owing to their bioavailability, biocompatibility, and biodegradability. Herein, a symmetrical azobenzene-functionalized natural glycyrrhizic acid (trans-GAG) was synthesized and could form stable supramolecular gels in DMSO/H2O and MeOH/H2O. Owing to trans–cis isomerization, this gel exhibited typical light-responsive behavior that led to a reversible gel–sol transition accompanied by a variation in morphology and rheology. Additionally, this trans-GAG gel displayed a distinct injectable self-healing property and outstanding biocompatibility. This work provides a simple yet rational strategy to fabricate stimuli-responsive materials from naturally occurring, eco-friendly molecules.
A promising catalyst for exclusive: Para hydroxylation of substituted aromatic hydrocarbons under UV light
Das, Vijay Kumar,Gogoi, Satyabrat,Choudary, Boyapati Manoranjan,Karak, Niranjan
, p. 4278 - 4283 (2017/09/29)
Herein, we describe a waterborne polymer/carbon dot nanocomposite system as an efficient, resourceful and sustainable photocatalyst for para-selective hydroxylation of substituted aromatic compounds using H2O2 under UV light. The polymer matrix and carbon dot generate a synergistic catalytic system. A unique structural attribute of the functionalities in this catalytic system attracts the aromatic substrates into close proximity and activates them. Additionally, the flexible molecular box-like structure of the hyperbranched polymer provides the ability for favorable three-point interaction with several substrates having various sizes by means of their multiple force networks and the increased accessibility of the active sites. The catalyst can be stored on the bench top for months and is reusable without considerable loss in its activity. The reaction was exclusively selective toward para hydroxylation irrespective of the nature of the substituents (electron donating or electron withdrawing) in the aromatic hydrocarbons. Hence, it is one of the most promising catalysts for selective hydroxylation of substituted aromatic hydrocarbons.
Facile, mild and convenient preparation and characterization of some novel schiff base ligands from synthetic diamines and salicylaldehyde
Naeimi, Hossein,Heidarnezhad, Arash
, p. 117 - 122 (2015/01/30)
Some novel Schiff base ligands have been prepared through condensation of salicylaldehyde with synthetic various primary diamines under mild reaction conditions. The used aromatic diamines were synthesized in good yields starting from low-cost commercially available materials. In these reactions, the Schiff base products have been afforded with excellent yields and appropriate reaction times. The structure of these ligands has been characterized by IR, 1H NMR and 13C NMR techniques.
Variable noninnocence of substituted azobis(phenylcyanamido)diruthenium complexes
Choudhuri, Mohommad M. R.,Behzad, Mahdi,Al-Noaimi, Mousa,Yap, Glenn P. A.,Kaim, Wolfgang,Sarkar, Biprajit,Crutchley, Robert J.
supporting information, p. 1508 - 1517 (2015/06/16)
The synthetic chemistry of substituted 4,4′-azobis(phenylcyanamide) ligands was investigated, and the complexes [{Ru(tpy)(bpy)}2( μ-L)][PF6]2, where L = 2,2′:5,5′-tetramethyl-4,4′-azobis(phenylcyanamido) (Me4adpc2-), 2,2′-dimethyl-4,4′-azobis(phenylcyanamido) (Me2adpc2-), unsubstituted (adpc2-), 3,3′-dichloro-4,4′-azobis(phenylcyanamido) (Cl2adpc2-), and 2,2′:5,5′-tetrachloro-4,4′-azobis(phenylcyanamido) (Cl4adpc2-), were prepared and characterized by cyclic voltammetry and vis-near-IR (NIR) and IR spectroelectrochemistry. The room temperature electron paramagnetic resonance spectrum of [{Ru(tpy)(bpy)}2( μ-Me4adpc)]3+ showed an organic radical signal and is consistent with an oxidation-state description [RuII, Me4adpc?-, RuII]3+, while that of [{Ru(tpy)(bpy)}2( μ-Cl2adpc)]3+ at 10 K showed a low-symmetry RuIII signal, which is consistent with the description [RuIII, Cl2adpc2-, RuII]3+. IR spectroelectrochemistry data suggest that [{Ru(tpy)(bpy)}2( μ-adpc)]3+ is delocalized and [{Ru(tpy)(bpy)}2( μ-Cl2adpc)]3+ and [{Ru(tpy)(bpy)}2( μ-Cl4adpc)]3+ are valence-trapped mixed-valence systems. A NIR absorption band that is unique to all [{Ru(tpy)(bpy)}2( μ-L)]3+ complexes is observed; however, its energy and intensity vary depending on the nature of the bridging ligand and, hence, the complexes oxidation-state description.
