Results 201 to 210 of about 7,397 (236)

Dimeric hydrolysable tannins from Tamarix pakistanica

Phytochemistry, 1993
Abstract Tamarixinins B and C, two new dimeric hydrolysable tannins, have been isolated from the flower extract of Tamarix pakistanica. Spectral data and chemical correlation with the known tannins by Smiles rearrangement established their structures, in which the monomeric units are linked to each other by isodehydrodigalloyl group(s).
Takashi Yoshida, Atalla H.F. Ahmed, Muhamad U. Memon, Takuo Okuda   +3 more
openaire   +1 more source

Hydrolysable tannins of Eucalyptus delegatensis wood

Phytochemistry, 1970
Abstract Five ellagitannins have been isolated from the wood of Eucalyptus delegatensis by fractionation with Sephadex and characterized by hydrolysis reactions and NMR spectra. They include 2,3- and 4,6-(hexahydroxydiphenoyl)-glucose, a di-(hexahydroxydiphenoyl)-glucose known as pedunculagin, and two more complex tannins of incompletely determined ...
Margaret K. Seikel, W.E. Hillis
openaire   +1 more source

Analysis of hydrolysable tannins

Animal Feed Science and Technology, 2001
This review deals with the main issues relating to the analysis of hydrolysable tannins (HTs). It covers briefly their distribution in the plant kingdom and describes their main structural features. HTs have often been ignored because they are apparently more difficult to analyse than condensed tannins.
openaire   +1 more source

Dimeric hydrolysable tannins from melastoma Malabathricum

Phytochemistry, 1992
Abstract Three new hydrolysable tannin dimers, malabathrins B, C and D, and 11 known tannins including three dimers (nobotanins B, G and H) and a trimer (nobotanin J), have been isolated from the leaves of Melastoma malabathricum. The structures of new dimers were determined by spectral analysis and chemical correlations with nobotanins B and J.
Takashi Yoshida, Fumihisa Nakata, Kumi Hosotani, Aya Nitta, Takuo Okudat   +4 more
openaire   +1 more source

Monomeric and dimeric hydrolysable tannins of Tamarix nilotica

Phytochemistry, 2009
An ellagitannin monomer, nilotinin M1 (1), and three dimers, nilotinins D1 (2), D2 (3), and D3 (4), were isolated from leaves of Tamarix nilotica (Ehrenb.) Bunge. Structures were elucidated based on analysis of spectroscopic data and chemical correlations with known compounds.
Mohamed A A, Orabi, Shoko, Taniguchi, Tsutomu, Hatano   +2 more
openaire   +2 more sources

Circular dichroism of hydrolysable tannins-II dehydroellagitannins

Tetrahedron Letters, 1982
Abstract The CD spectra of dehydroellagitannins and related compounds have empirically shown that the absolute configuration at C-1′ of the dehydrohexahydroxydiphenoyl group can be determined by the Cotton effect around 200 nm.
Takuo Okuda, Takashi Yoshida, Tsutomo Hatano, Toshitaka Koga†, Namiko Toh†, Kaoru Kuriyama††   +5 more
openaire   +1 more source

Hydrolysable tannins and proanthocyanidins from green tea

Phytochemistry, 1984
Abstract Two hydrolysable tannins were isolated from green tea, and their structures were characterized by chemical and spectral means as 1,4,6-tri- O -galloyl-β- d -glucose and 1- O -galloyl-4,6-(−)-hexahydroxydiphenoyl-β- d -glucose. In addition, a new proanthocyanidin gallate was isolated, together with the known procyanidins B-2, B-4 and C-1 ...
Gen-Ichiro Nonaka, Ryo Sakai, Itsuo Nishioka   +2 more
openaire   +1 more source

Methylation, acetylation and gel permeation of hydrolysable tannins

Journal of Chromatography A, 1994
Abstract Different derivatization methods for hydrolysable tannins were compared and assessed for calibration of gel permeation systems. Methylation of ellagitannins such as vescalagin or castalagin with either diazomethane or dimethyl sulphate yields small amounts of the expected permethylated products together with several by-products resulting ...
Carole Viriot, Augustin Scalbert, Catherine L.M. Hervé du Penhoat, Christian Rolando, Michel Moutounet   +4 more
openaire   +3 more sources

Condensed and Hydrolysable Tannins as Antioxidants Influencing the Health

Mini-Reviews in Medicinal Chemistry, 2008
Natural polyphenols are a wide class of secondary plant metabolites and represent an abundant antioxidant component of human diet. An important, but often neglected group of natural polyphenols, are tannins. This review offers a general description of chemistry of both hydrolysable and condensed tannins (proanthocyanidins), the mechanisms of their ...
Vit, Koleckar, Katerina, Kubikova, Zuzana, Rehakova, Kamil, Kuca, Daniel, Jun, Ludek, Jahodar, Lubomir, Opletal   +6 more
openaire   +2 more sources

Differential scanning calorimetry of hydrolysed mangrove tannin

Polymer International, 2000
Mangrove-bark-tannin adhesives are potential substitutes for phenol–formaldehyde (PF) wood-bonding adhesives which are derived from petroleum, a finite natural resource. However, mangrove-bark-tannin adhesive exhibits poor adhesive properties, including brittleness, poor wet strength, and poor wood penetration.
S Sowunmi, R?O Ebewele, O Peters, A?H Conner   +3 more
openaire   +1 more source