1,721,034 research outputs found
Comments on Truffle Aroma Analysis by Headspace Solid Phase Microextraction [Is butylated hydroxytoluene (BHT) a "natural "volatile constituent of truffles?]
No full textGC-MS represents a powerful analytical thecnique that allows a quick and easy determination of VOCs. But the great deal of structural data should be examined critically in order to avoid mistakes
On some Derivatives of 2-Hydroxyglutaric Acid
No full textS- and R-acetoxyglutaric acid dimethyl esters are synthesized starting from S and R glutamic acids. Specific optical rotation values given in the literature for some derivatives of 5-oxo-2-S-tetrahydrofuronic acid, an intermediate in the above synthesis, are corrected
Attempted Nucleophilic Attack of Cyanide Ion on alfa-beta-unsaturated p-Tosylhydrazones.
No full textThe reactivity of alfa-beta-unsaturated p-Tosylhydrazones toward ion cyanide as nucleophile. In a aqueous-dichloromethane two-phases reaction, using benzyltriethyammonium chloride as a phase-transfer catalyst, we obtained hydrocyanation of tosylhydrazones of cycloexanone and other unconjugated substrates, while the C=N of conjugated one, resists nucleophilic attack of cyanide ion
Composizione ed evoluzione del profumo di alcuni fiori del territorio modenese.
No full textLa composizione del profumo dei fiori di Syringa Vulgaris si modifica durante il periodo della fioritura. Le variazioni dei componenti volatili sono state analizzate e messe in correlazione con analoghi cambiamenti da noi riscontrati in altre specie vegetali
Le trasformazioni dei composti organici volatili responsabili dell'aroma dell'aceto balsamico tradizionale di Modena
No full textSono stati determinati via GC-MS i composti organici responsabili dell'aroma dell'Aceto Balsamico Tradizionale di Modena e le loro trasformazioni durante l'invecchiamento
A Route to 3,4-Polymethylenepyrazoles via Olefinic Toluene-p-sulphonylhydrazones
No full textTosylhydrazones of cycloalkenyl carbonyl compounds were subjected to base-catalysed decomposition (K2CO3-MeOH) in aim to obtain 3,4-polymethylenepyrazoles. The cycloaddition occours in high yelds and solvolysis competes with cycloaddition only with cyclopentenyl derivative
TRIMETHYLCHLOROSILANE-MEDIATED FORMATION OF 2-CHLOROCYCLOHEXYL SULPHIDES BY SULPHOXIDES
No full textThe title 2-chlorocyclohexyl sulfides, e.g. I (R = Me, Et, Me2CH, Bu) were prepd. by treating cyclohexene with the corresponding alkyl sulfoxides RSOR in the presence of Me3SiCl. Unsym. sulfoxides, e.g. EtSOBu gave a mixt. of products I (R = Et, Bu). Tetramethylene sulfoxide (II) gave aldehyde I (R = CH2CH2CH2CHO) as the major product. A mechanism is presented in which 2 mol. of sulfoxide form an intermediates S-alkoxysulfonium salt
The Configuration of the C(5) Carbon Atom in the Germacranic Sesquiterpene Ageratriol
No full textThe configuration R for the C(5) atom in ageratriol has already been proposed on the basis of the results of asymmetrical esterification. It is now confirmed by transformation into a meso compound
Stereospecific Cyclisation of Agerol to an Isovetivane Carbon Framework
No full textAcid-catalysed conversion of a germacrane sesquiterpene into compounds with the unknown isovetivane framework was carried out by using aqueous acetic aci
N-N Bond Cleavage of 1-Acyl-2p-tosylhydrazines with Sulphur Mono- and Di-chloride.
No full textThe distribution of main products of the reaction of 1-Acyl-2p-tosylhydrazines with S2Cl2, SCl2, SOCl2 and SO2Cl2 is summarized
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