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Lavrenov SN Korolev AM Reznikova MI Sosnov AV Preobrazhenskaya MN 《Carbohydrate research》2003,338(2):143-152
Alkaline degradation of the ascorbigen 2-C-[(indol-3-yl)methyl]-alpha-L-xylo-hex-3-ulofuranosono-1,4-lactone (1a) led to a mixture of 1-deoxy-1-(indol-3-yl)-L-sorbose (2a) and 1-deoxy-1-(indol-3-yl)-L-tagatose (3a). The mixture of diastereomeric ketoses underwent acetylation and pyranose ring opening under the action of acetic anhydride in pyridine in the presence of 4-dimethylaminopyridine (DMAP) with the formation of a mixture of (E)-2,3,4,5,6-penta-O-acetyl-1-deoxy-1-(indol-3-yl)-L-xylo-hex-1-enitol (4a) and (E)-2,3,4,5,6-penta-O-acetyl-1-deoxy-1-(indol-3-yl)-L-lyxo-hex-1-enitol (5a), which were separated chromatographically. Deacetylation of 4a or 5a afforded cyclised tetrols, tosylation of which in admixture resulted in 1-deoxy-1-(indol-3-yl)-3,5-di-O-tosyl-alpha-L-sorbopyranose (12a) and 1-deoxy-1-(indol-3-yl)-4,5-di-O-tosyl-alpha-L-tagatopyranose (13a). Under alkaline conditions 13a readily formed 2-hydroxy-4-hydroxymethyl-3-(indol-3-yl)cyclopenten-2-one (15a) in 90% yield. Similar transformations were performed for N-methyl- and N-methoxyindole derivatives. 相似文献
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Indole glucosinolate breakdown and its biological effects 总被引:1,自引:0,他引:1
Most species in the Brassicaceae produce one or more indole glucosinolates. In addition to the parent indol-3-ylmethylglucosinolate
(IMG), other commonly encountered indole glucosinolates are 1-methoxyIMG, 4-hydroxyIMG, and 4-methoxyIMG. Upon tissue disruption,
enzymatic hydrolysis of IMG produces an unstable aglucone, which reacts rapidly to form indole-3-acetonitrile and indol-3-ylmethyl
isothiocyanate. The isothiocyanate, in turn, can react with water, ascorbate, glutathione, amino acids, and other plant metabolites
to produce a variety of physiologically active indole compounds. Myrosinase-initiated breakdown of the substituted indole
glucosinolates proceeds in a similar manner to that of IMG. Induction of indole glucosinolate production in response to biotic
stress, experiments with mutant plants, and artificial diet assays suggest a significant role for indole glucosinolates in
plant defense. However, some crucifer-feeding specialist herbivores recognize indole glucosinolates and their breakdown products
as oviposition and/or feeding stimulants. In mammalian diets, IMG can have both beneficial and deleterious effects. Most IMG
breakdown products induce the synthesis of phase 1 detoxifying enzymes, which may in some cases prevent carcinogenesis, but
in other cases promote carcinogenesis. Recent advances in indole glucosinolate research have been fueled by their occurrence
in the well-studied model plant Arabidopsis thaliana. Knowledge gained from genetic and biochemical experiments with A. thaliana can be applied to gain new insight into the ecological and nutritional properties of indole glucosinolates in other plant
species. 相似文献
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Korolev AM Yudina LN Rozhkov II Lysenkova LN Lazhko EI Luzikov YN Preobrazhenskaya MN 《Carbohydrate research》2001,330(4):713-477
A facile preparation is described of 3-(indol-3-yl)-2-hydroxy-4-hydroxymethylcyclopent-2-enone and its N-derivatives in 15-40% yields by the degradation of ascorbigen or its N-derivatives in a warm solution of L-ascorbic acid through a sequential domino reaction. The same cyclopentenone derivatives were obtained in 30-40% yields by the condensation of (N-alkylindol-3-yl)glycolic acids with ascorbic acid. 2,6-Dihydroxy-1-(indol-3-yl)hexa-1,4-diene-3-one and 2-hydroxy-4-hydroxymethyl-5-(indol-3-yl)cyclopent-2-enone were identified as intermediates in this reaction. 相似文献
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