0000000000346959

AUTHOR

Antonio Selva

showing 3 related works from this author

Cardopatine and isocardopatine, two novel cyclobutane substances from Cardopatium corymbosum

1978

Two new natural substances containing a cyclobutane unit, cardopatine and isocardopatine, the trans and cis isomers respectively of 5,5″ (cyclobut-1,2-ylene-diethynylene)bis 2,2′-bithiophene), together with the known α-terthienyl and 5-(but-3-en-1-ynyl)-2,2′-bithienyl, have been isolated from the roots of Cardopatium corymbosum. Evidence is given that the novel cyclobutane substances are not the products of a spontaneous dimerization of a bithienyl monomeric unit. Structure determination and conformational analysis are reported.

chemistry.chemical_compoundMonomerchemistryStereochemistryMass spectrumCardopatium corymbosumPlant ScienceGeneral MedicineHorticultureMolecular BiologyBiochemistryCis–trans isomerismCyclobutanePhytochemistry
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Guest-to-host proton transfer in melatonin-beta-cyclodextrin inclusion complex by ionspray, fast atom bombardment and tandem mass spectrometry.

2001

Ionspray (IS) and fast atom bombardment (FAB) positive ionization mass spectrometry (MS) of 1:1 β-cyclodextrin (β-CD)-melatonin (MLT) host-guest complex allowed the detection of gaseous protonated 1:1 β-CD-MLT. Tandem MS collision-induced dissociation (CID) of such protonated 1:1 β-CD-MLT species showed the proton (charge) to be retained to a significant extent by the host and by its cage fragmentation products, in spite of the higher proton affinity of MLT with respect to that of β-CD. This requires an endothermic guest-to-host proton transfer to occur within the gaseous association. Collisional activation could be accounted for by the promotion of such an endothermic process; however…

Spectrometry Mass Electrospray IonizationFast atom bombardmentTandem mass spectrometryAnalytical chemistryBeta-CyclodextrinsProtonationSpectrometry Mass Fast Atom BombardmentPhotochemistryTandem mass spectrometryDissociation (chemistry)Inclusion compoundchemistry.chemical_compoundFragmentation (mass spectrometry)CyclodextrinSpectroscopyβ-cyclodextrin host-guest complexeMelatoninCyclodextrinsbeta-Cyclodextrinsbeta-CyclodextrinFast atom bombardmentElectrosprayEndothermic guest-to-host proton transferAlgorithmchemistryIonsprayProton affinityAlgorithmsJournal of mass spectrometry : JMS
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Structural and physicochemical characterization of the inclusion complexes of cyclomaltooligosaccharides (cyclodextrins) with melatonin

2002

The stoichiometry, geometry, stability, and solubility of the inclusion complexes of melatonin (MLT) with native cyclomaltooligosaccharides (α-, β- or γ-cyclodextrins, CDs) are determined experimentally by high-resolution NMR spectroscopy, calorimetric and solubility measurements, and mass spectrometry. The observed differences are discussed in terms of molecular recognition expression of the host-guest (h-g) interactions within the hydrophobic CDs cavities of different size. The 1:1 h-g stoichiometry in water solution prevails at low CD concentrations; the trend to form higher order associations is observed at increasing CD concentrations. The stability order β-CD>γ-CD>α-CD for the c…

Models MolecularSpectrometry Mass Electrospray IonizationElectrospray ionizationProtonationCalorimetryCalorimetryMass spectrometryBiochemistryInclusion complexeAnalytical ChemistryExcipientsMolecular recognitionCyclodextrinSolubilityNuclear Magnetic Resonance BiomolecularMelatoninCyclodextrinsMass spectrometryChemistryOrganic ChemistryGeneral MedicineNuclear magnetic resonance spectroscopyNMRCrystallographySolubilityThermodynamicsStoichiometry
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