Amino acids are an important and highly dynamic fraction of organic N in soils and their determination in soil without derivatization is challenging due to the difficulties in separation and detection of trace amounts of these polar analytes. In the present work, we developed an analytical metho...

The goal of the present study was to explore, in our previously developed hybrid template, the effect of introduction of additional heterocyclic rings (mimicking catechol hydroxyl groups as bioisosteric replacement) on selectivity and affinity for the D3 versus D2 receptor. In addition, we wante...

A new practical synthesis of 17α-acetoxy-11β-(4-N,N-dimethylaminophenyl)-19-norpregna-4,9-diene-3,20-dione (CDB-2914) is described. The synthesis gives easily isolable solids at all steps and is amenable to large-scale process.

The surface of mesoporous M41S silica material was functionalized with 3-aminopropyl and methyl groups and with mixtures of both. The ratio of the two groups on the silica surface could be adjusted by changing the molar ratio of the corresponding alkoxysilanes in the reaction mixture. The fracti...

The generation of an unexpected Brønsted acidity in anhydrous DMF at 50 °C was evidenced by NMR measurements during the investigation on the course of sucrose cleavage by ceric ammonium nitrate (CAN). The formation of a nitrooxy derivative of DMF by reaction with CAN is responsible for this aci...

Poly(4-vinylpyridinium) perchlorate has been used as an efficient solid acid catalyst for the synthesis of 3,3'-(arylmethylene)bis(4-hydroxycoumarins) and bis(indolyl)methanes, with the products being formed in excellent yields over very short reaction times under mild and environmentally f...

A method was developed in which phenothiazine derivatives were titrated visually to a colorless end‐point with ceric sulfate. Quantitative recoveries were obtained only for chlorpromazine, acetylpromazine, trifluoperazine, and triflupromazine. The method was also applied to pharmaceutical dosag...

In search of economical and effective catalysts it was found that IrCl3, a sluggish catalyst in alkaline media, surpasses catalytic efficiency of osmium and ruthenium in aqueous perchloric acid medium in the oxidation of aliphatic ketones by ceric perchlorate. Rate decreases in the beginning at ...

2,2′-Phthaloyl-, 2,2′-isophthaloyl, and 2,2′-terephthaloyl-bis[1, 1, 1-trimethylhydrazinium] dihydroxide, bis(inner salts) 7, 8, and 9 and their hydrazide and hydrazinium diiodide precursors were synthesized and tested for toxicity and their ability to block sympathetic ganglionic transmissio...

Monodispersed TiO2 hybrid microspheres were prepared via the hydrolysis of titanium isopropoxide (TTIP) in ethanol solution containing p-aminophenylacetic acid (APA). The effects of the APA:TTIP molar ratio, water content, reaction time and reaction temperature on the morphology of the resultant...

The FT-IR, 1H NMR, electrospray mass spectrometry studies of several dipeptides containing 3-APA (3-aminophenylacetic acid) and Aib/Val/Pro, revealed that all peptides share a common structural feature, an extended backbone conformation and they form the intermolecular hydrogen bonded supramolec...

In this study, in which the group vibrations of 3-aminophenylacetic acid were investigated by electronic structure calculations based on Density Functional Theory (DFT), the possible stable conformers of the molecule were searched through a relaxed “potential energy surface scan” carried out a...

A novel method for preparing cell support membrane which employs heterogeneously cross-linking (CR) process to prepare water-insoluble gelatin (GEL) films was suggested, and compared with 1-ethyl-(3,3-dimethylaminopropyl)carbodiimide. In this study, we found that 2-chloro-1-methylpyridinium iodi...

A spectrophotometric study of the Cd(II) and Cu(II) complex of a new reagent, 2-(5-bromo-2-pyridylazo)-5-diethylamino phenol (5-Br-PADAP) in the presence of polyglycol octylphenyl ether (OP) is presented. A reddish binary complex is formed at pH 9 and shows maximal absorbance at 560 nm with mola...

Resonance Raman (RR) and, in aqueous silver colloids, Surface Enhanced Raman (SER) spectra of both uranyl(VI) and 2-(5-bromo-2-pyridylazo)-5-diethylaminophenol (Br-PADAP) have been studied. The neutral Br-PADAP molecule had previously been shown to appear mainly as a type Z tautomer (zwitterion ...

A method for the simultaneous determination of Nb and Ta in steel and alloy by reversed-phase high-performance liquid chromatography (RP-HPLC) was proposed. 2-(5-Bromo-2-pyridylazo)-5-diethylamino phenol (5-Br-PADAP) was used as a pre-column chelating agent to form a ternary complex with Nb(V) a...

A rapid spectrophotometric method for the determination of Pd in titanium alloys is proposed. It is based on the reaction of 2-(5-bromo-2-pyridylazo)-5-(diethylamino)phenol with Pd(II) in a sulphuric acid medium in the presence of ethanol. Beer's law is obeyed up to 40 μg of Pd. The molar ...

An optical chemical sensor based on immobilization of 2-(5-bromo-2-pyridylazo)-5-(diethylamino)phenol (Br-PADAP) in Nafion membrane is described. The membranes were cast onto glass substrates and were used for the determination of nickel in aqueous solutions by spectrophotometry. The sensor syst...

A novel optical chemical sensor has been developed for the determination of thallium(III) in aqueous solutions using 4-(5-bromo-2-pyridylazo)-5-(diethylamino)-phenol (Br-PADAP) as a complex agent. The optode membrane was prepared from plasticized PVC. Formation of the complex between thallium(II...

The metal–ligand mole ratios and the stability constants of the Cu(II), Co(II), Ni(II) and Zn(II) complexes at 2-(5-bromo-2-pyridylazo)-5-diethylamino)phenol were determined using a spectrophotometric method at different temperatures (20, 30, 40 and 50±0.1 °C) and ionic strengths (0.05, 0.1 a...