Química

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https://hdl.handle.net/10669/281

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Examinando Química por Autor "Achenbach, Hans"

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    Chemical Investigations of Tropical Medicinal Plants, XXI [1] Long Chain Alkyl Esters of Ferulic and p-Coumaric Acid from Bauhinia manca
    (1986) Stöcker, Markus; Constenla Umaña, Manuel Arturo; Achenbach, Hans
    Bauhibia manca (Leguminosae) is a vine growing in the lowland forests of Costa Rica and Panama [2]. In Costa Rica, an infusion of the stems and leaves is taken as an astringent and diuretic, and as a remedy for diabetes[3,4] An antidiabetic effect is also claimed by a pharmacological study [5]. Since nothing is known about the constituents of Bauhinia manca we started phytochemical investigations of the woody parts of this plant. from the petrol extract a number of long-chain alkyl esters of ferulic and p-coumaric were isolated.
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    Constituents of Fevillea cordifolia: New Norcucurbitacin and Cucurbitacin Glycosides
    (1993) Achenbach, Hans; Waibel, Reiner; Hefter Bübl, Ursula; Constenla Umaña, Manuel Arturo
    The seeds of Fevillea cordifolta have yielded 11 new fevicordin-type 29- norcucurbitacins 3-13, and two new cucurbitacin glycosides 14 and 15, which were isolated along with previous reported fevicordin A [2] and its glucoside [1]. Structure determinations are based on spectroscopic studies and on chemical interconversions.
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    Fevicordin A and Fevicordin A Glucoside, Novel Norcucurbitacins from Fevillea cordifolia
    (1987) Achenbach, Hans; Hefter Bübl, Ursula; Constenla Umaña, Manuel Arturo
    From the seeds of the Central American Fevillea cordifolia (Cucurbitaceae) fevicordin A glucoside (1) and fevicordin A (2) members of the novel norcucurbitacin group, were isolated.
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    Flavonoid and other constituents of Bauhinia manca
    (1988) Achenbach, Hans; Stöcker, Markus; Constenla Umaña, Manuel Arturo
    Phytochemical analysis of the stem of Bauhiniu munca yielded 63 compounds, among them six new natural products. Major constitutents were found to be 3-0-galloylepicatechin, gallic acid, cinnamic acid, /3-sitosterol and its B-D-glucoside. The two new flavans possess significant antifungal activity.
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    Ítem
    Gaschromatographische Analyse des Samenfettes der mittelamerikanischen Fevillea Cordifolia (Cucurbitaceae)
    (1992) Achenbach, Hans; Hefter Bübl, Ursula; Waibel, Reiner; Constenla Umaña, Manuel Arturo; Hahn, Horts
    The fat of the seeds of Fevillea cordifolia was extracted under exclusion of oxygen and light and then characterized by 13C-NMR in regard to the contained unsaturated acid moieties. The total fat was separated by HPLC to yield one major fraction (˜ 45%), one medium fraction (˜ 18%) and some minor fractions. All substantial fractions showed the chromophore of a conjugated triene. According to MS-analysis the major fraction consists of distearyleleostearylglycerol. The total fat was converted by transesterification to a mixture of fatty acids methyl esters, which was analyzed by subsequent HPLC and GC: Main fatty acids were found to be stearic acid (53%) and the triple conjugated α-eleostearic acid (31%). Interestingly, punicic acid, which is isomeric to α-eleostearic acid and contained in various seed fats of Cucurbitaceae plants, could not be detected.