03 Fakultät Chemie

Permanent URI for this collectionhttps://elib.uni-stuttgart.de/handle/11682/4

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1981 - 19863

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Institute: search.filters.UBSInstitut.Sonstige EinrichtungAuthor: search.filters.author.Effenberger, FranzSubject: search.filters.subject.540Start date: 1980End date: 1989

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Now showing 1 - 3 of 3
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    A novel synthetic route to L-proline (Amino acids ; 7)
    (1986) Drauz, Karl-Heinz; Kleemann, Axel; Martens, Jürgen; Scherberich, Paul; Effenberger, Franz
    Reaction of L-5-oxoproline esters L-2 with phosgene at 0° C gives L-5,51-dichloro-1-(chlorocarbonyl)proliene esters L-6 ,which readily lose hydrogen chloride to form L-5-chloro-1-(chloroarbonyl)-4,5-dehydroproline esters L-7. Catalytic hydrogenation (Pd/C, 180 bar) of L-7 yields L-1-(chlorocarbonyl)proline esters L-15 and thence, upon hydrolysis, L-proline ( L17 ). A "one-pot reaction" for the whole sequence is described, starting from easily accessible L-5-oxoproline esters and yielding L-proline in 78% overall yield and 99.7% optical purity.
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    The effect of N-methyl-formimino-methylester on the neural olfactory threshold in albino mice
    (1984) Schmidt, C.; Schmidt, Uwe; Breipohl, Winrich; Effenberger, Franz
    The effects of N-methyl-formimino-methylester were studied in albino mice. Very short exposure (0.5 and 1 s) to the concentrated vapour led to an increase of the neural olfactory threshold to geraniol . There was a slow recovery of the olfactory sensitivity and after about 40 days the threshold values returned to normal.
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    Light microscopical investigations (Chemical blockade of olfactory perception by N-methylformimino-methylester in albino mice ; 2)
    (1981) Rehn, Bernd; Breipohl, Winrich; Schmidt, C.; Schmidt, Uwe; Effenberger, Franz
    Evidence is given that N-methyl-formimino-methylester (MFM), a highly volatile substance, causes olfactory receptor cell degeneration in mice. The time course of this degeneration and morphological changes in the compartment of receptor cell progenitor cells are described. Due to the morphological appearance of the progenitor cells and their dynamic transformation after exposure to MFM, two different types of progenitor cells can be distinguished: (a) light-staining globose basal or blastema cells, which are thought to be real progenitor cells and to remain in the mitotic cycle for generating new sensory cells; and (b) dark-staining basal cells with condensed chromatin, which are quiescent. The results agree with electrophysiological data indicating temporary inhibition of olfactory perception after MFM.