Search results for "Note"

Synthesis of elemane bis-lactones structurally related to vernolepin

1998

Abstract The chemical transformation of santonin into an elemane bis -lactone structurally related to the antitumour compound vernolepin is reported. The transformation of ring A of santonin into a hemiacetal δ-lactone was achieved in eleven steps. The spectroscopic characteristics of the synthetic product obtained in this way revealed that the proposed structure for the natural product should be revised.

Tetrazine Click Chemistry for the Modification of 1-Hydroxy-1,1-methylenebisphosphonic Acids: Towards Bio-orthogonal Functionalization of Gold Nanopa…

2016

Inverse electron demand Diels-Alder (iEDDA) was evaluated for the functionalization of gold nanoparticles. The reaction was first modelled with the free coating molecule 1-hydroxy-1,1-methylenebisphosphonate bearing an alkene functionality (HMBPene). A model tetrazine 3,6-dipyridin-2-yl-1,2,4,5-tetrazine (pyTz) was used, kinetic of the reaction was calculated and coupling products were analysed by NMR and HRMS. The reaction was then transposed at the nanoparticle surface. Gold nanoparticles bearing an alkene functionality were obtained using a one-pot methodology with HMBPene and the tetrazine click chemistry was evaluated at their surface using pyTz. The successful coupling was assessed by…

DNA Sensors for the Detection of Biomolecules and Biochemical Conditions

2017

Composite clay sorbents for immobilisation of biomolecules and cells

2015

Precision Anisotropic Brush Polymers by Sequence Controlled Chemistry

2020

The programming of nanomaterials at molecular length-scales to control architecture and function represents a pinnacle in soft materials synthesis. Although elusive in synthetic materials, Nature has evolutionarily refined macromolecular synthesis with perfect atomic resolution across three-dimensional space that serves specific functions. We show that biomolecules, specifically proteins, provide an intrinsic macromolecular backbone for the construction of anisotropic brush polymers with monodisperse lengths via grafting-from strategy. Using human serum albumin as a model, its sequence was exploited to chemically transform a single cysteine, such that the expression of said functionality is…

Multilayered Modelling of the Metallation of Biological Targets

2021

The unique property of metals – the remarkable ability to modulate the electronic structure of both metal center and bound ligands – is the reason for their omnipresence in enzymes and in metal-coordinating biological factors. Modern metallodrug chemistry began with the serendipitous unveiling of the antitumour properties of cisplatin, followed by an avalanche of synthesized novel metallodrugs. The metallation of biological targets has then become a new paradigm in the field of bioinorganic chemistry, and a plethora of computational approaches have been developed and utilized to ease the detailed comprehension of its mechnisms with a focus on medical applications. Studies of the electronic …

Solid state electrochemical behavior of organosulfur compounds

2017

Abstract The solid-sate electrochemistry of organosulfur compounds existing in petroleum and its derived matrices is described using the voltammetry of immobilized microparticles methodology. Cyclic and square wave voltammogrammetric responses of sulfur compounds responsible of aging of asphalt pavements, namely, thiophenes, disulfides, sulfides, sulfoxides and sulfones were determined at compound-modified graphite electrodes in contact with 0.10 M H2SO4. The electrochemical oxidation/reduction products were characterized by attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) and scanning electron microscopy with energy dispersion x-ray detection (SEM-EDX) couple…

A missing member in the family of chalcogenophene-substituted 2,2′:6′,2″-terpyridine: 4′-(tellurophen-2-yl)-2,2′:6′,2″-terpyridine, its Ru(II) comple…

2019

Abstract The new terpyridine derivative 4’-(tellurophen-2-yl)-2,2′:6′,2″-terpyridine and its homoleptic Ru(II) complex have been prepared and characterized by different techniques (NMR, UV–Vis, mass spectrometry). Additionally, a thin polymer film was obtained through electrochemical oxidation and coupling of tellurophene moieties. The obtained organic coating showed very interesting electrochemical and electrochromic properties, thanks to its Ru(terpy)2 groups.

Clickable poly-L-lysine for the formation of biorecognition surfaces

2019

Biomolecules are immobilized onto surfaces employing the fast and stable adsorption of poly-l-lysine (PLL) polymers and the versatile copper-free click chemistry reactions. This method provides the combined advantages of versatile surface adsorption with density control using polyelectrolytes and of the covalent and orthogonal immobilization of biomolecules with higher reaction rates and improved yields of click chemistry. Using DNA attachment as a proof of concept, control over the DNA probe density and applicability in electrochemical detection are presented.

Coil overlap in moderately concentrated polyelectrolyte solutions: effects of self-shielding as compared with salt-shielding as a function of chain l…

2016

The generalized intrinsic viscosity {η} (hydrodynamic volume of the solute at arbitrary polymer concentration c) – introduced by analogy to the intrinsic viscosity [η] – provides access to the degree of coil overlap Ω for polyelectrolyte solutions in pure water or in saline water. The experimental basis of this investigation consists in viscosity measurements as a function of c for a large number of sodium polystyrene sulfonate (Na-PSS) samples covering the molecular weight range from 0.91 to 1000 kg mol−1. The accurate modeling of these dependencies with a maximum of three parameters yields detailed information on Ω as a function of (c[η]) in the absence and in the presence of extra salt. …