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Lactone Derivatives (lactone + derivative)

Distribution by Scientific Domains
Chemistry100%

Selected Abstracts

ChemInform Abstract: Synthesis of Heterocycle-Annulated Medium-Sized Oxacycles and Lactone Derivative by Intramolecular Heck Reaction.

CHEMINFORM, Issue 52 2009
K. C. Majumdar
Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source]

First (Peroxo)vanadium(V) Complex with Heteroligand Formed in Reaction System , Synthesis, Structure and Reactivity of K[VO(O2)(omeida)]·H2O {omeida = N -[2-(2-oxomorpholine-4-yl)ethyl]iminodiacetato(2,)}

EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 11 2003
Michal Sivák
Abstract The crystalline peroxo complex of vanadium(V), K[VO(O2)(omeida)]·H2O, where omeida is a ,-lactone derivative, N -[2-(2-oxomorpholine-4-yl)ethyl]iminodiacetate(2,), has been obtained by reaction of vanadate with H2O2 and N -(2-hydroxyethyl)ethylenediaminetriacetic acid (HEDTA) in acidic aqueous solution at pH = 3 and 278 K. X-ray analysis revealed a distorted pentagonal-bipyramidal coordination around the vanadium atom, with a typical cis arrangement of oxo and peroxo ligands in apical and equatorial positions, respectively. Two amino nitrogen atoms of the tetradentate omeida(2,)-N1,N2,O1,O2 ligand occupy the neighbouring equatorial positions of the pentagonal plane, and two oxygen atoms of carboxymethyl groups bound to the same N1 nitrogen atom are in equatorial and apical positions. The six-membered lactone ring in omeida was formed in the reaction solution from carboxy and hydroxy groups not involved in coordination with the vanadium atom. The 51V NMR spectra of K[VO(O2)(omeida)]·H2O, and of peroxovanadate/HEDTA/H2O and vanadate/HEDTA/H2O solutions, as well as the 1H NMR spectrum of HEDTA, proved that lactone ring closure proceeds only in peroxovanadate but not vanadate solutions. Spectroscopic investigation of the oxygen transfer reaction from the peroxo ligand in [VO(O2)(omeida)], to the thiolato sulfur atom in [Co(en)2{S(CH2)2NH2}]2+ or [Co(en)2(cyst)]+, and of the oxidation of N -acetyl- L -cysteine by K[VO(O2)(omeida)]·H2O, revealed much more complicated reaction mechanisms than those of other (amino-polycarboxylato)monoperoxo complexes of vanadium(V). (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003) [source]

Mass spectrometry analysis of terpene lactones in Ginkgo biloba

RAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 6 2008
Shujing Ding
Terpene lactones are a family of compounds with unique chemical structures, first recognised in an extract of Ginkgo biloba. The discovery of terpene lactone derivatives has recently been reported in more and more plant extracts and even food products. In this study, mass spectrometric characteristics of the standard terpene lactones in Ginkgo biloba were comprehensively studied using both an ion trap and a quadrupole time-of-flight (QTOF) mass spectrometer. The mass spectral fragmentation data from both techniques was compared to obtain the mass spectrometric fragmentation pathways of the terpene lactones with high confidence. The data obtained will facilitate the analysis and identification of terpene lactones in future plant research via the fragmentation knowledge reported here. Copyright © 2008 John Wiley & Sons, Ltd. [source]

Ruthenium-catalyzed carbonylative cycloaddition reactions involving carbonyl and imino groups as assembling units

THE CHEMICAL RECORD, Issue 4 2008
Naoto Chatani
Abstract This paper describes carbonylative cycloaddition reactions catalyzed by Ru3(CO)12. Ru3(CO)12 was found to catalyze an intramolecular Pauson,Khand-type reaction. Carbonylative cycloaddition reactions involving a carbonyl group in aldehydes, ketones, and esters as a two-atom assembling unit were also achieved in the presence of Ru3(CO)12 as the catalyst. The reaction of 5-hexyn-1-al and 6-heptyn-1-al derivatives with CO in the presence of Ru3(CO)12 resulted in cyclocarbonylation from which bicyclic ,, ,-unsaturated lactones were obtained. Intermolecular [2,+,2,+,1] carbonylative cycloaddition of alkenes, ketones, and CO was also catalyzed by Ru3(CO)12 as the catalyst to give saturated ,-lactone derivatives. Simple ketones were not applicable, but ketones having a CO or CN group at the ,-position served as a good substrate. These reactions could be extended to carbonylative cycloaddition of the corresponding imines leading to ,-butyrolactam derivatives. The [4,+,1] carbonylative addition of ,,,-unsaturated imines leading to unsaturated ,-lactams was achieved with Ru3(CO)12. © 2008 The Japan Chemical Journal Forum and Wiley Periodicals, Inc. Chem Rec 8: 201,212; 2008: Published online in Wiley InterScience (www.interscience.wiley.com) DOI 10.1002/tcr.20149 [source]