Despite the well-known anti-mycobacterial actions of isoniazid (INH) and rifampicin (RIF), the clinical success of tuberculosis (TB) therapy requires prolonged administration of multiple drugs in high doses, which often result in frequent adverse effects and low patient adherence. Although liposomes are promising candidates for controlled delivery of anti-TB drug, the high cost...
The fast decolourization of multi-purpose dye, Brilliant blue (BB-) oxidized by chlorine dioxide was investigated using the stopped flow technique under varied pH conditions by monitoring its oxidation kinetics. The products were identified and reaction mechanism is described, which is confirmed by kinetic simulations. Under [ClO2]0 > [OH-]0 > [BB-]0 conditions, the oxidation...
The oxidation of the biologically-active thiol, N-acetyl-d-penicillamine (NDPen) by acidified iodate and aqueous iodine has been studied. The stoichiometry of the reaction is 1:1 in which the thiol (RSH) is oxidized to its sulfonic acid (RSO3H) without cleavage of the C-S bond. In excess acidified iodate the reaction displayed a short induction period, followed by formation of...
The treatment of calcium chloride with sodium carbonate under solvent-free conditions with a supersonic airflow and at a low heating temperature leads to the synthesis of ultra-fine calcium carbonate. The reaction not only involves mild conditions, a simple operation, and high yields but also gives a high conversion rate.
Degradation studies of β-cyclodextrin polymers cross-linked with toluene-2,4-diisocyanate (TDI) and hexamethylene diisocyanate (HMDI) were carried out by exposing the polymers to different soil types for up to 120 days. The aim of the study was to determine the fate of these novel polymers in the environment. The polymers were either digested with sulphuric acid prior to...
The dissolution of Icel-Aydincik dolomite in aqueous hydrochloric acid solution was investigated with respect to the effects of acid/dolomite mole ratio, solid/liquid ratio, particle size, stirring speed, time and temperature. It was observed that solubility of the dolomite ore increased with increasing acid/dolomite mole ratio, stirring speed, period of time, temperature, and...
Nitration of 4-hydroxybenzaldehyde afforded 2,6-dinitro-4-hydroxybenzaldehyde 2, which in the presence of thionyl chloride is converted to 4-chloro-2,6-dinitrobenzaldehyde 3. This compound is very reactive towards nucleophiles, and reacts easily with methoxyamine, affording the intermediate 4-aminomethoxy-2,6-dinitrobenzaldehyde 4. Reaction of 4 with N-t-butyl-hydroxylamine led...
N-Bromosuccinimide (NBS) catalyses the ring opening of various epoxides with different thiols in CH3CN at room temperature under mild reaction conditions. The corresponding β-hydroxysulphides are obtained in short reaction times and in good to high yields with nearly complete regioselectivity. The catalyst was compared with previously reported catalysts and only one that we have...
LiNi0,5Mn1,5O4 compounds were prepared through a solid-state reaction using various Ni precursors. The effect of the precursors on the electrochemical performance of LiNi0,5Mn1,5O4 was investigated. LiNi0,5Mn1,5O4 made from Ni(NO3)2 ● 6H2O shows the best charge-discharge performance. The reversible capacity of LiNi0,5Mn1,5O4 is about 145 mA h g-1 and remained at 143 mA h g-1...
A theoretical (DFT) study of the equilibrium geometry of the possible reaction products of the oxidative addition reaction [Rh(FcCOCHCOCF3)(CO)(PPh3)] + CH3I (Fc = ferrocenyl), consistent with experimental observations, revealed that the first alkyl product results from trans addition to RhI. Isomerization via an acyl intermediate leads to a second octahedral alkyl product with...
Synthesis of new a-aminophosphonic acid esters (3a-I) was accomplished by the reaction of equimolar quantities of phenyl ethyl glycine and various aryl aldehydes with diethyl/ dimethylphosphite in dry toluene at reflux temperature. All the structures of the newly synthesized a-aminophosphonic acid esters (3a-I) were established by elemental analysis, and IR, 1H, 13C, 31P NMR and...
Electron-donating substituted anilines were converted to their corresponding nitro compounds with sodium perborate in the presence of a catalytic amount of silica sulphuric acid under micellar media in moderate to good yields.
99mTc-DMSA (DMSA=dimercaptosuccinic acid), the gold standard for static renal imaging, has a long uptake time, which is a limiting factor in diagnostic procedures and also leads to a relatively high radiation dose to patients. The ligands dimethyl biguanide (DMBG), biuret (BIU), 2-imino-4-thiobiuret (ITB) and carboxy-biguanide (CBIG) have nitrogen donor atoms, which are able to...
The hydrophobic cobyrinic acid heptapropyl ester corrinoids XCbs-Pr (axial ligandX = CN-,SO32-,CH3- and CH3CH2-) have been prepared from vitamin B12 by hydrolysis of the amide side chains and their conversion to propyl esters. Both the position of the y-band and the general shape of the UV-visible spectra of these complexes show significant solvent dependence as the polarity of...
A rapid and efficient condensation reaction of 2-aminothiophenol with various fatty acids in solvent-free conditions with or without microwave irradiation was carried out to afford the corresponding 2-substituted benzothiazole derivatives in good to excellent yields. The structures of the new products were established by elemental analyses, IR, 1H NMR, 13C NMR and mass spectral...
A series of novel diselenides 5a-e were synthesized from α-haloketones, α-picoline alkenes and various secondary amines under a dry nitrogen atmosphere. The structures of these compounds were established by means of their spectral data and they were screened for scavenging activity against 1,1-diphenyl-2-picryl-hydrazyl (DPPH.). The results of this research showed that two of...
The study of the self-assembly properties of peptides and proteins is important for the understanding of molecular recognition processes and for the rational design of functionalbiomaterials. Novel bolaamphiphilic peptides and peptide hybrids incorporating non-natural aminoacids were designed around a model lysine/leucine-rich peptide with the intention to study their self...
A series of MAl2O4:Eu2+,Sm3+ (M = Ca, Sr, Ba) phosphors was prepared by the combustion method, and the influence of these alkaline earth metals on the structure and luminescent performances for these phosphors was investigated. A relationship was established between their composition, crystallization capacity and luminescent properties. The results show that the CaAl2O4: Eu2+,Sm3...
1-phenyl-3-(2-thenoyl)-1,3-propanedione, Hbth, pKa' = 9.006(8) and 1,3-di(2-thenoyl)-1,3-propanedione, Hdtm, pKa' = 8.893(3) were prepared by the Claisen condensation of ethyl 2-thiophenecarboxylate with an appropriate ketone under the influence of lithium diisopropylamide (LDA). The group electronegativity of the thienyl group is 2.10 (Gordy scale) as calculated from a linear...
Efficient oxidation of various types of structurally diverse alcohols to the corresponding carbonyl compounds can be carried out with N, N,-dibromo-N, N,-1,2-ethanediylbis(benzenesulphonamide) in good to high yield of products in CH2Cl2 at room temperature. Primary (aliphatic, benzylic and allylic) alcohols are oxidized with no over-oxidation to carboxylic acids.
A convenient, straightforward, two-step reaction of α-hydroxyhydrocarbylphosphonates with arylisothiocyanates in the presence of catalytic amounts of sodium methoxide in 1,2-dichloroethane as solvent produced various new α-(arylamino thiocarbonyloxy) hydrocarbylphosphonates in excellent yields. Their structures have been confirmed by their IR, 1H NMR and 31P NMR spectra and by...
A dinuclear complex [Dy(m-MBA)3phen]2-H2O was prepared by the reaction of DyCl3-6H2O, m-methylbenzoic acid and 1,10-phenanthroline in a 1:3:1 molar ratio, where m-MBA = m-methylbenzoate and phen = 1,10-phenanthroline. The complex was structurally characterized by single crystal X-ray diffraction, elemental analysis, UV and IR spectroscopy, molar conductance and TG-DTG techniques...
The diethyl ether extract of the aerial parts of Artemisia abrotanum L. was analyzed by GC and GC/MS. The main identified constituents were silphiperfol-5-en-3-one A (14.6 %), ascaridole (13.1 %), 1,8-cineole (10.5 %), α-bisabolol oxide A acetate (8.7 %), germacrene D (6.5 %) and borneol (6.0 %).