Search results for " complex"

Enantioselective recognition of alfa-amino acids by binary complexes fluorophore/cyclodextrin

Binary complexes heptakis-(6-amino)-(6-deoxy)-beta-cyclodextrin/fluorophore: structural investigation and chiral recognition

Complexation equilibria between beta-cyclodextrin and p-nitroaniline derivatives in mixed solvent media: a polarimetric study

Binding porperties of hetpakis-(2,6-di-O-methyl)-beta-cyclodextrin and mono-(3,6-anydro)-beta-cyclodextrin

Tworzenie kompleksów inkluzyjnych pomiędzy 5-fluorouracylem a β-cyklodekstrynami

2017

Celem przedstawionego opracowania jest omówienie najważniejszych zagadnień dotyczących chemioterapii z użyciem 5-fluorouracylu, jego metabolizmu oraz zagrożenia wynikające z leczenia tym chemioterapeutykiem. Poruszona została również kwestia możliwości ograniczenia toksyczności 5FU, przez zainkludowaniu go we wnętrzu molekuły β-cyklodekstryny. Przedstawiono również najważniejsze wyniki badań teoretycznych w których przedstawiono geometrię kompleksu inkluzyjnego 5FU⎼βCD. Struktura została zoptymalizowana na poziomie teorii funkcjonału gęstości (DFT) z użyciem metody B3LYP/6-31G. Wykazano istnienie przynajmniej jednego wiązania wodorowego pomiędzy grupą aminową 5FU, a grupą hydroksylową powie…

Mesolithic pit-sites in Champagne (France): First data, key issues

2015

International audience; In less than a decade, more than 30 sites and around 200 deep pits dated to the Mesolithic have been identied in the Champagne-Ardenne region (north-eastern France). This paper describes the main characteristics of these features and provides some clues for their interpretation. This unexpected but apparently common type of site clearly implies a more marked territoriality and a greater social complexity than generally proposed for the period in continental northern France.

Combined dynamics of the 500–600 nm leaf absorption and chlorophyll fluorescence changes in vivo: Evidence for the multifunctional energy quenching r…

2021

Carotenoids (Cars) regulate the energy flow towards the reaction centres in a versatile way whereby the switch between energy harvesting and dissipation is strongly modulated by the operation of the xanthophyll cycles. However, the cascade of molecular mechanisms during the change from light harvesting to energy dissipation remains spectrally poorly understood. By characterizing the in vivo absorbance changes (Delta A) of leaves from four species in the 500-600 nm range through a Gaussian decomposition, while measuring passively simultaneous Chla fluorescence (F) changes, we present a direct observation of the quick antenna adjustments during a 3-min dark-to-high-light induction. Underlying…

Non-linear optical, electrochemical and spectroelectrochemical properties of amphiphilic inner salt porphyrinic systems

2016

Three zwitterionic meso-substituted A3B- and AB2C-porphyrins containing one sulfonato alkylpyridinium substituent and three or two alkoxy-substituted phenyl groups were synthesized in good yield and fully characterized as to their physicochemical properties by a variety of techniques. This new series of inner salt donor-acceptor meso-substituted porphyrin derivatives were prepared for possible application as amphiphilic probes for membrane insertion in the area of combined second-harmonic and two-photon fluorescence cellular microscopy. To this end, the linear and nonlinear optical properties of the compounds were characterized, together with their electrochemical and spectroelectrochemica…

A new copper(II) chelate complex with tridentate ligand: Synthesis, crystal and molecular electronic structure of aqua-(diethylenetriamine-N, N′, N′′…

2015

Abstract The crystals of a new aqua-(diethylenetriamine-N, N′, N′′)-copper(II) sulfate monohydrate have been synthesized by direct interaction of solid copper(II) sulfate pentahydrate with diethylenetriamine (deta). The crystal structure of [Cu(deta)H2O]SO4⋅H2O (1) has been determined by X-ray diffraction methods at 100 K and characterized using X-ray powder diffraction pattern: space group P 1 ¯ , a = 7.2819(4), b = 8.4669(4), c = 8.7020(3) A, α = 83.590(3), β = 89.620(4), γ = 84.946(4)°, Z = 2. The environment of the Cu(II) atom is a distorted, elongated square pyramid which consists of three nitrogen atoms of the deta molecule and oxygen atom of the water molecule in the basal plane of t…

A new copper(II) chelate complex with polyamines as fire retardant and epoxy hardener: Synthesis, crystal and electronic structure, and thermal behav…

2020

A new (ethylenediamine-N,N′)-(diethylenetriamine-N,N′,N″)-copper(II) hexafluoridosilicate complex, [Cu(eda)(deta)]SiF6 (1) (eda – ethylenediamine; deta – diethylenetriamine), was synthesized by direct interaction of anhydrous CuSiF6 with polyethylenepolyamine (pepa – H2N[C2H4NH]nH, where n = 1 (eda) and 2 (deta)). The crystals of 1 were characterized by IR spectroscopy and X-ray diffraction. Compound 1 consists of SiF62− discrete anions and [Cu(eda)(deta)]2+ complex cations whose Cu2+ ions are chelated by eda and deta. The coordination polyhedron of Cu(II) atom is an elongated square pyramid which consists of four nitrogen atoms belonging to NH2 groups of eda and NH2 and NH groups of …