Facile Denitrosation of Cyclic N-Nitrosamines with Hydrazoic Acid

Abstract

A simple and facile method for the denitrosation of cyclic N-nitrosamines using HN₃ (concentrated H₂SO₄ + NaN₃) is reported. In this method, limited usage of this reagent does not affect the carbonyl group.     

An Easy Route to (Hetero)arylboronic Acids

An unprecedented spontaneous reactivity between diazonium salts and diboronic acid has been unveiled, leading to a versatile arylboronic acid synthesis directly from (hetero)arylamines. This fast reaction (35 min overall) tolerates a wide range of functional groups and is carried out under very mild conditions. The radical nature of the reaction mechanism has been investigated.     

Semiconducting and photoelectrochemical properties of the ilmenite CoTiO3 prepared by wet method and its application for O2 evolution under visible light

Journal of Solid State Electrochemistry - The ilmenite CoTiO3 was synthesized by chemical route, and the decomposition of nitrates was followed by thermal analysis (TG/DTA). The intermediate...     

3-T MR-guided brachytherapy for gynecologic malignancies

Gynecologic malignancies are a leading cause of death in women worldwide. Standard treatment for many primary and recurrent gynecologic cancer cases includes external-beam radiation followed by brachytherapy. Magnetic resonance (MR) imaging is beneficial in diagnostic evaluation, in mapping the tumor location to tailor radiation dose and in monitoring the tumor response to treatment. Initial studies of MR guidance in gynecologic brachytherapy demonstrate the ability to optimize tumor coverage and reduce radiation dose to normal tissues, resulting in improved outcomes for patients.     

New basic catalysts obtained from layered double hydroxides nanocomposites

A new route for the preparation of basic mixed oxides using nanocomposite precursors obtained from layered double hydroxides (LDH) was investigated. These nanocomposites have been prepared by intercalation of negatively charged guest entities containing Ca²⁺, Sr²⁺, Ba²⁺ or La³⁺ cations in the interlayer space of host Mg/Al LDH by anionic exchange. The guest entities have been previously prepared by complexation of the required cations in the presence of edta or citrate chelating anions. Intercalation of [Mⁿ⁺(edta)]^(4?n)? or [La(cit)OH]^? complexes is proved by elemental analysis, XRD analysis and FT-IR spectroscopy. However, in order to satisfy the charge equilibrium in the materials, (edta)^4? and (citrate)^3? species are also co-intercalated in the nanocomposites. The basic properties of the mixed oxides obtained after thermal decomposition of the nanocomposites precursors were evaluated in the disproportionation of 2-methyl-3-butyn-2-ol (MBOH) and the transesterification of 1-phenylethanol with diethylcarbonate (DEC). The Sr- and Ba-containing mixed oxides exhibit basicity close to the one of MgO and Mg(La)O mixed oxides. A comparative study of the reactivity of La-containing mixed oxides obtained following different preparation routes, i.e. coprecipitation or anionic exchange, allows to conclude that the nanocomposite route led to the most active samples.     

Multidimensional Quaternionic Gabor Transforms

In this paper, we extend the Gabor transform to the quaternion valued functions on \({\mathbb{R}^{d}}\) in two different ways, where \({d\in \mathbb{N}}\) is arbitrary. We prove that the quaternionic Gabor transforms satisfy the properties including Parseval relation, inversion formula, linearity and uncertainity principle. We also present an extension of a quaternionic Gabor transform to Boehmians.     

Nickel Confined in the Interlayer Region of Birnessite: an Active Electrocatalyst for Water Oxidation

We report a synthetic method to enhance the electrocatalytic activity of birnessite for the oxygen evolution reaction (OER) by intercalating Ni²⁺ ions into the interlayer region. Electrocatalytic studies showed that nickel (7.7 atomic %)‐intercalated birnessite exhibits an overpotential (η) of 400 mV for OER at an anodic current of 10 mA cm^?2. This η is significantly lower than the η values for birnessite (η≈700 mV) and the active OER catalyst β‐Ni(OH)₂ (η≈550 mV). Molecular dynamics simulations suggest that a competition among the interactions between the nickel cation, water, and birnessite promote redox chemistry in the spatially confined interlayer region.     

Exact solitary solutions of an inhomogeneous modified nonlinear Schrödinger equation with competing nonlinearities

We employed both tanh and sine–cosine function methods to study the inhomogeneous modified nonlinear Schrödinger (IMNLS) equation and constructed its exact solitary solutions by using symbolic computation software. We compared the solutions obtained by both the methods.     

New pharmacological insights of Galactia glaucescens

Galactia glaucescens leaves are popularly used against snakebites in Brazil. The hydroethanolic extract from aerial parts of G. glaucescens (HEGg) was assayed against the neurotoxicity and myotoxicity induced by Bothrops jararacussu venom. A traditional myographic technique was applied for neurotoxicity and the resulting muscles were treated routinely by light microscopy analysis for myotoxicity. Additionally, the antimicrobial potential of HEGg was evaluated against Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa strains, as well as Rutin was isolated for the first time in this specie using chromatographic and spectroscopic methods and its antiophidian property was assessed. HEGg totally prevents the neurotoxicity and myotoxicity effects caused by B. jararacussu, but did not show any antimicrobial effect. Concluding, HEGg and Rutin were able to counteract the toxic effects of the venom and confirmed the antiophidian potential, but not antimicrobial, of G. glaucescens as an alternative for neutralization of B. jararacussu venom.