Biomedical subjects

Hideyuki Ito

Publications and source records attributed to Hideyuki Ito.

40 records · Page 3Linked to original sources

PubMed2002

Proanthocyanidin glycosides and related polyphenols from cacao liquor and their antioxidant effects.

Purification of polar fractions from cacao liquor extracts gave 17 phenolics including four new compounds. The new compounds were characterized as a C-glycosidic flavan, an O-glycoside of a dimeric and two O-glycosides of trimeric A-linked proanthocyanidins, on the basis of spectroscopic data. Isolated polyphenols showed inhibitory effects on nicotinamide adenine dinucleotide phosphate-dependent lipid peroxidation in microsomes and on the autoxidation of linoleic acid. These effects were attributed to the radical-scavenging activity in the peroxidation chain reactions, based on the findings that the cacao polyphenols effectively scavenged the 1,1-diphenyl-2-picrylhydrazyl radical.

Animals↗

PubMed2002

Dimeric and trimeric hydrolyzable tannins from Quercus coccifera and Quercus suber.

Three new hydrolyzable tannins, cocciferins D(1) (1), D(2) (2), and T(1) (4), were isolated from the leaves of Quercus coccifera. Cocciferin D(2) (2) and two additional new tannins, cocciferins D(3) (3) and T(2) (5), were also obtained from the leaves of Quercus suber. Their oligomeric structures were elucidated on the basis of spectroscopic methods and chemical evidence. Compounds 2, 3, and 5 were rare oligomers possessing glucose cores with both open-chain and pyranose forms.

Algeria↗

PubMed2002

Accumulation of hydrolyzable tannins by Aleurites fordii callus culture.

A callus culture of Aleurites fordii Hemsley (Euphorbiaceae) producing five galloylglucoses and an ellagitannin, geraniin, was established. The production of pentagalloylglucose was remarkably enhanced under light irradiation compared with that in the dark. Cell growth and tannin production were also greatly affected by changing the concentrations and composition of nitrogen sources.

Aleurites↗

PubMed1996

Synthesis of Trideca-O-methyl-alpha-pedunculagin. Diastereo-Favoritism Studies on Intramolecular Ester-Cyclization of Axially Chiral Diphenic Acids with Carbohydrate Core.

Total synthesis of trideca-O-methyl-alpha-pedunculagin was achieved by a simple sequence. The key step is the synthesis of methyl 4,6-O-benzylidene-2,3-O-[(S)-4,4',5,5',6,6'-hexamethoxydiphenoyl]-alpha-D-glucopyranoside through intramolecular ester-cyclization of racemic hexamethoxydiphenoyl chloride with methyl 4,6-O-benzylidene-alpha-D-glucopyranoside at the 2,3-position. The diastereoselectivity results obtained in the intramolecular cyclization of hexamethoxydiphenic acid to the carbohydrate core raises a very interesting point in considering the pathway of (R)-diphenic acid biosynthesis.

Journal Article↗