Results 171 to 180 of about 4,664 (206)

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 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. 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 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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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 Related Polyphenols fromPistacia weinmannifolia

Planta Medica, 2000
Two new gallotannins, pistafolins A (1) and B (2), were isolated from the leaf extract of Pistacia weinmannifolia. Their structures were determined by spectral methods. Four known gallotannins (3-6), seven known flavonoid glycosides (7-13), along with 1-O-beta-D-(6'-O-galloyl)-glucopyranosyl-3-methoxy-5-hydroxybenzen e (14), gallic acid (15), methyl ...
A J, Hou, L Y, Peng, Y Z, Liu, Z W, Lin, H D, Sun   +4 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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Gallotannin Determination Using HPLC

2003
Pipette 1 ml of supernatant A (see Section 5) into the above mentioned culture tubes, remove acetone in a vacuum oven adjusted at 40°C (pressure 300 mbar). It takes about 3 h to remove acetone. Acetone can also be removed by flushing with nitrogen gas. Dry the contents completely in a heating block at 40°C by flushing with nitrogen.
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Gallotannin Biosynthesis: A New β-Glucogallin-dependent Galloyltransferase from Sumac Leaves Acylating Gallotannins at Positions 2 and 4

Journal of Plant Physiology, 1999
Summary Leaves of Saghorn sumac (Rhus typhina) contain. several isoenzymes that catalyze the R-glucogallin (1-O-galloyl-β-D-glucose)-dependent transformation of 1,2,3,4,6-penta-O-galloyl-β-D-glucose to complex gallotannins. Among these, a new galloyltransferase has been isolated that preferentially acylated the 4-position of the substrate, followed ...
Ruth Niemetz, Georg G. Gross
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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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