Sharif Digital Repository

Alzheimer’s disease (AD) is an irreversible neurological disorder that progresses gradually and can cause severe cognitive and behavioral impairments. This disease is currently considered a social and economic incurable issue due to its complicated and multifactorial characteristics. Despite decades of extensive research, we still lack definitive AD diagnostic and effective therapeutic tools. Consequently, one of the most challenging subjects in modern medicine is the need for the development of new strategies for the treatment of AD. A large body of evidence indicates that amyloid-β (Aβ) peptide fibrillation plays a key role in the onset and progression of AD. Recent studies have reported... 

A five-coordinated Fe(III) complex with the distorted trigonal bipyramidal configuration was synthesized by reactions of FeCl36H2O and 2-(2′-hydroxyphenyl)oxazoline (Hphox) as a bidentate ON donor oxazoline ligand. Complex [Fe(phox)2Cl] was fully characterized, including by single-crystal X-ray structure analysis. DFT calculations were accompanied with experimental results in order to obtain a deeper insight into the electronic structure and vibrational normal modes of complex. Oxidation of sulfides to sulfoxides in one-step was conducted by this complex as catalyst using urea hydrogen peroxide (UHP) in mixture of CH2Cl 2/CH3OH (1:1) under air at room temperature. The results show that using... 

A new binuclear copper(ii) complex, namely [Cu2L(pz)(DMSO)], where L = 2,6-bis[(2-phenoxy)iminomethyl]-4-methylthiophenolate(3-) and pz = pyrazolate ligand, has been synthesized by a one-pot synthesis involving copper(ii) acetate monohydrate, the S-protected ligand precursor 2-(N,N-dimethylthiocarbamato)-5-methylisophthalaldehyde di-2′-hydroxy anil, (I), and pyrazole, in which a metal-promoted S-deprotection reaction occurs during the formation of the complex. This was characterized by routine physicochemical studies, single crystal X-ray diffraction and electron paramagnetic resonance (EPR) techniques. The structure analysis reveals that there are copper centres in two different... 

Here, the carboxamide ligand N-(thiazole-2-yl) picolinamide (L) was synthesized in an ionic liquid tetrabutylammonium bromide (TBAB) as the benign reaction medium. The sensitivity of L towards different metal-ions was investigated, and a comprehensive, logical optical investigation was conducted for the IIB transition metal ions, Hg2+, Cd2+ and Zn2+, based on off-on switch sensor protocols. In the absence of these metal ions, L showed weak emission only, but fluorescence intensity increased considerably upon their addition to a sensitivity range of 10-6 M. This phenomenon was enhanced significantly in the presence of Zn2+ compared to other metal ions, likely due to the coordination of... 

A series of new ternary zinc(II) complexes [Zn(L1-10)(phen)], where phen is 1,10-phenanthroline and H2L1-10 = tridentate Schiff base ligands derived from the condensation of amino acids (glycine, l-phenylalanine, l-valine, l-alanine, and l-leucine) and salicylaldehyde-5-sulfonates (sodium salicylaldehyde-5-sulfonate and sodium 3-methoxy-salicylaldehyde-5-sulfonate), have been synthesized. The complexes were characterized by elemental analysis, IR, UV-vis, 1H NMR, and 13C NMR spectra. The IR spectra of the complexes showed large differences between νas(COO) and νs(COO), Δν (νas(COO) - νs(COO)) of 191-225 cm-1, indicating a monodentate coordination of the carboxylate group. Spectral data... 

The mechanism of surfactants in surfactant-in situ chemical oxidation (S-ISCO) coupled process for trichloroethene (TCE) degradation was firstly reported. The performance of TCE solubilization and inhibition of TCE degradation in three nonionic surfactants (TW-80, Brij-35, TX-100) in PS/Fe(II)/citric acid (CA) system was compared and TW-80 was evaluated to be the optimal surfactant in S-ISCO coupled process due to the best TCE solubilizing ability and minimal inhibition for TCE degradation (only 31.8% TCE inhibition in the presence of 1 g L−1 TW-80 surfactant). The inhibition mechanism in TCE degradation was also demonstrated by comparing the strength of ROSs and PS utilization. In the... 

Dopamine is one of the most important neurotransmitters released by neurons in the central nervous system, and a variety of neurological illnesses and mental disorders are associated with impairments in the secretion and functionality of dopamine. Dopamine, depending on the type of receptors, can act as a stimulant or an inhibitor. In this study, dendrimer-conjugated dopamine was utilized as a chelating agent for Technetium-99m to investigate the organ distribution of this compound in vivo using the single-photon emission computed tomography (SPECT) technique. For this purpose, dendrimers were synthesized using polyethylene glycol diacid and citric acid precursors, and dopamine was...