Results 211 to 220 of about 6,629 (239)

Antitumor-promoting activities of hydrolyzable tannins in mouse skin

Carcinogenesis, 1992
Ellagic acid and gallic acid and its derivatives, applied topically to female CF-1 mice 20 min before each 12-O-tetradecanoylphorbol-13-acetate (TPA) treatment inhibit the inductions of epidermal ornithine decarboxylase activity, hydroperoxide production and DNA synthesis caused by this potent tumor promoter in relation with their abilities to inhibit ...
H U, Gali, E M, Perchellet, D S, Klish, J M, Johnson, J P, Perchellet   +4 more
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Hydrolyzed Tannins of Euphorbia glareosa Leaves. Structure of Glarein C

Chemistry of Natural Compounds, 2000
The structure of glarein, a new hydrolyzed tannin from Euphorbia glareosa Pall. ex Bieb. leaves, was established using physicochemical properties of the compound itself, its hydrolysis products, and IR, UV, and PMR spectra.
L. N. Gvazava, M. D. Alaniya
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Hydrolyzable Tannins having a Depsidone-forming Valoneoyl Group

HETEROCYCLES, 1990
The orientation of the valoneoyl group in praecoxins C and D as in the structures of praecoxins C and D was unequivocally proved by the 1 H- 13 C long-range shift correlation spectrum of rugosin C which was chemically correlated with praecoxin ...
Takuo Okuda, Tsutomu Hatano, Osamu Namba, Ling Chen, Taeko Yasuhara, Kazufumi Yazaki, Takashi Yoshida   +6 more
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Gallic Acid Derivatives and Hydrolyzable Tannins

1989
Gallic acid and its derivatives as they occur in extracts of oak-galls constitute a chemical reagent of considerable antiquity. The blue-black color produced when an aqueous infusion is treated with salts of iron was first described by Pliny; its use in the analysis of mineral waters and as a component of invisible ink were noted as early as the ...
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Hydrolyzable tannin substances

Chemistry of Natural Compounds, 1975
T. K. Chumbalov, T. N. Bikbulatova
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Enzymes in the Biosynthesis of Hydrolyzable Tannins

1992
The two classes of hydrolyzable tannins (i.e., gallotannins and ellagitan-nins) have long been postulated to originate from 1,2,3,4,6-pentagalloyl-glucose as their common precursor. The biosynthesis of this pivotal ester was studied with enzymes from oak and sumac leaves. β-Glucogallin (l-O-galloyl-β-D-glucose), the first intermediate of this metabolic
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Hydrolyzable Tannins

2012
Jourdes, M., Pouységu, L., Quideau, S., Mattivi, Fulvio, Truchado, P., Tomás Barberán, F. A.   +5 more
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Tannin structural elucidation and quantitative ³¹P NMR analysis. 2. Hydrolyzable tannins and proanthocyanidins.

Journal of agricultural and food chemistry, 2014
An unprecedented analytical method that allows simultaneous structural and quantitative characterization of all functional groups present in tannins is reported. In situ labeling of all labile H groups (aliphatic and phenolic hydroxyls and carboxylic acids) with a phosphorus-containing reagent (Cl-TMDP) followed by quantitative ³¹P NMR acquisition ...
Federica, Melone, Raffaele, Saladino, Heiko, Lange, Claudia, Crestini   +3 more
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Biosynthesis, Biodegradation, and Cellular Localization of Hydrolyzable Tannins

1999
Tannins occupy a prominent position among plant polyphenols, not only because of their widespread occurrence in the plant kingdom but also on grounds of their technological, ecological, and medical significance. Unfortunately, it is impossible to describe simply this large group of natural products on the basis of a common, general chemical structure ...
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Hydrolyzable Tannins: Gallotannins and Ellagitannins

2013
Michaël Jourdes, Laurent Pouységu, Denis Deffieux, Pierre-Louis Teissedre, Stéphane Quideau   +4 more
openaire   +1 more source