Results 101 to 110 of about 1,075 (155)

The structure of gallotannins

Chemistry of Natural Compounds, 1973
1. It has been established that the semiacetal hydroxyls of the carbohydrate components of the tannins of the smoketree and of Turkish galls are substituted by galloyl residues and the C3 hydroxy group is free; on the other hand, in the tannins from sumac and Chinese galls all the hydroxy groups of the sugars are substituted by galloyl residues with ...
I. Sh. Buziashvili, N. F. Komissarenko, I. P. Kovalev, V. G. Gordienko, D. G. Kolesnikov   +4 more
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Gallotannins. Part XIII. The structure of Chinese gallotannin: evidence for a polygalloyl chain

Journal of the Chemical Society C: Organic, 1966
Evidence is presented relating to the disposition of the depsidically linked galloyl groups on the penta-O-galloyl-β-D-glucose core of Chinese gallotannin. Interpretation of the n.m.r. spectra of methylated gallotannin fractions using the spectra of model depsides and several tri-O-methylgalloyl sugar derivatives permits the tentative formulation of ...
G. Britton, P. W. Crabtree, E. Haslam, J. E. Stangroom   +3 more
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Gallotannins. Part XIV. Structure of the gallotannins

Journal of the Chemical Society C: Organic, 1967
Structures are suggested for the principal naturally occurring polyesters of gallic acid, based upon 1H n.m.r. spectroscopy. The mass-spectroscopic behaviour of methylated Chinese gallotannin is described.
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Gallotannins and flavonoids from Haematoxylon campechianum

Phytochemistry, 1996
Two new compounds, 2,6-bis-O-digalloyl-3-O-galloylglucose and 2-O-trigalloyl-1,3,4,6-tetrakis-O-galloylglucose, along with four known gallotannins, were isolated and identified from the leaves of Haematoxylon campechianum. In addition, four known flavonoid and three simple phenolic compounds were also detected.
F E, Kandil, N H, el-Sayed, H N, Micheal, M S, Ishak, T J, Mabry   +4 more
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Gallotannins are uncompetitive inhibitors of pancreatic lipase activity

Biophysical Chemistry, 2020
Inhibition of pancreatic lipase (PL) is used to treat dyslipidemias and obesity. Phenolic compounds are highly bioactive molecules that can inhibit various enzymes. Our aim was to evaluate the inhibitory activity of selected phenolic compounds of increasing molecular complexity, namely, phenolic acids, mangiferin, penta-O-galloyl-β-d-glucose (PGG) and ...
Elena N. Moreno-Córdova, Aldo A. Arvizu-Flores, Elisa M. Valenzuela-Soto, Karina D. García-Orozco, Abraham Wall-Medrano, Emilio Alvarez-Parrilla, J. Fernando Ayala-Zavala, J. Abraham Domínguez-Avila, Gustavo A. González-Aguilar   +8 more
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Pyrethrin and Gallotannin in the Flowers of Peony

Nature, 1962
FROM a light petroleum extract of dried petals of peony (Peonia albiflora Pall.) an oily substance (74.08 per cent C, 9.94 per cent H) was isolated by means of nitromethane extraction. It comprises 0.13 per cent of the dry weight of petals and 18 per cent of light petroleum extracts and shows in the ultraviolet spectral region maxima at 227 and 280 mµ ...
I. CHMIELEWSKA, Z. KASPRZYK
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Mechanistic Studies on the Antidiabetic Properties of Gallotannins

Current Pharmaceutical Design
The escalating prevalence of type 2 diabetes (T2DM) has emerged as a global public health dilemma. This ailment is associated with insulin resistance and heightened blood glucose concentrations. Despite the rapid advancements in modern medicine, where a regimen of medications is employed to manage blood glucose effectively, certain treatments ...
Xueqing, Li, Wei, Wu, Yuting, Liu, Jiale, Zhao, Yibei, Gui, Hailin, Wang, Lijun, Wang, Yiyang, Luo, Gang, Zhou, Yumin, He, Chengfu, Yuan   +10 more
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Determination of Gallotannins in Beer by Gas Chromatography

Proceedings. Annual meeting - American Society of Brewing Chemists, 1971
(1971). Determination of Gallotannins in Beer by Gas Chromatography. Proceedings. Annual meeting - American Society of Brewing Chemists: Vol. 29, Proceedings of the Annual Meeting 1971, pp. 171-182.
Helen Trachman, Leonard T. Saletan
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Biosynthesis and Biodegradation of Complex Gallotannins

1999
According to an already classical definition formulated by Freudenberg in 1920,1 plant tannins are divided into condensed tannins (nowadays often referred to as proanthocyanidins), which are derived from C-C linked flavan-3-ol units, and into hydrolyzahle tannins. The latter are characterized by a central polyol moiety (β-D-glucose in most cases) whose
Ruth Niemetz, Joerg U. Niehaus, Georg G. Gross   +2 more
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Gallotannine und Ellagen-gerbstoffe

1956
Wenn uber Fortschritte der Chemie der Gallotannine berichtet werden soll, so mus ein Ausgangspunkt gewahlt werden, von dem aus die neu gewonnenen Erkenntnisse geschildert werden. Das ist in unserem Falle nicht schwer. Emil Fischer hatte fur das chinesische Gallotannin (aus den Blattgallen von Rhus semialata) und das turkische Gallotannin (aus den ...
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