490-61-9Relevant academic research and scientific papers
General synthesis of epi-series catechins and their 3-gallates: Reverse polarity strategy
Ohmori, Ken,Yano, Takahisa,Suzuki, Keisuke
supporting information; experimental part, p. 2693 - 2696 (2010/08/21)
A general synthetic route to the epi-series catechins was developed based on the reverse polarity strategy. Aromatic nucleophilic substitution reaction followed by the sulfinyl-metal exchange and cyclization enabled stereo-controlled access to various members of epi-series catechins and their 3-gallates.
Enantioselective synthesis of afzelechin and epiafzelechin
Wan, Sheng Biao,Chan, Tak Hang
, p. 8207 - 8211 (2007/10/03)
The flavonoids afzelechin and epiafzelechin as well as their gallate esters were synthesized enantioselectively via Sharpless hydroxylation followed by regioselective cyclization. Graphical Abstract
New oligomeric proanthocyanidine from Ziziphus jujuba
Malik, Aibek,Kuliev,Akhmedov,Vdovin,Abdullaev
, p. 40 - 42 (2007/10/03)
Chemical and spectral data establish the structure of an oligomeric proanthocyanidine PZ-5 isolated from Ziziphus jujuba.
(+)-AFZELECHIN 3-RHAMNOSIDE FROM CASSIPOUREA GERRARDII
Drewes, Siegfried E.,Taylor, Craig W.,Cunningham, Anthony B.
, p. 1073 - 1075 (2007/10/02)
A new flavanol glycoside has been isolated from the bark of Cassipourea gerrardii.Its structure has been established from spectroscopic and hydrolytic studies as (+)-afzelechin 3-O-α-L-rhamnopyranoside.Delayed homonuclear COSY studies show up interesting long-range couplings between specific protons. Key words: Cassipourea gerrardii; Rhizophoraceae; bark; (+)-afzelechin 3-O-α-L-rhamnopyranoside.
Tannins and Related Compounds. LXI. Isolation and Structures of Novel Bi- and Triflavanoids from the Leaves of Cassia fistula L.
Morimoto, Satoshi,Nonaka, Gen-Ichiro,Chen, Rong-Fu,Nishioka, Itsuo
, p. 39 - 47 (2007/10/02)
Together with (-)-epiafzelechin (1) and its 3-O-glucoside (4), (-)-epicatechin (2) and procyanidin B-2 (3), seven new biflavanoids (5-7, 9-12) and two triflavanoids (8, 13) have been isolated from the leaves of Cassia fistula L. (Leguminosae).On the basis of chemical and spectroscopic evidence, the structures of 5-8 were established to be proanthocyanidins each having (-)-epiafzelechin unit(s) in the molecule, while 9-13 were shown to consist of (2S)-7,4'-dihydroxyflavan and (-)-epiafzelechin units.Keywords - Cassia fistula; Leguminosae; proanthocyanidin; flavan-3-ol glucoside; flavan-3-ol; flavan; condensed tannin; thiolytic degradation; acid-catalyzed condensation
Tannins and Related Compounds. LVI. Isolation of Four New Acylated Flavan-3-ols from Oolong Tea. (1)
Hashimoto, Fumio,Nonaka, Gen-Ichiro,Nishioka, Itsuo
, p. 611 - 616 (2007/10/02)
A chemical examination of the aqueous acetone extract of commercial oolong tea has led to the isolation of four new acylated flavan-3-ols 1-4, together with the known compounds 5-13.On the basis of chemical and spectroscopic evidence, compounds 1-4 have been characterized as (-)-epiafzelechin 3-O-gallate (1), (-)-epicatechin 3-O-(4-O-methyl)-gallate (2), (-)-epicatechin 3-O-p-hydroxybenzoate (3) and (-)-epigallocatechin 3-O-cinnamate (4).
(-)-EPIAFZELECHIN 5-O-β-D-GLUCOSIDE FROM CRATAEVA RELIGIOSA
Sethi, V. K.,Taneja, S. C.,Dhar, K. L.,Atal, C. K.
, p. 2402 - 2404 (2007/10/02)
Epiafzelechin 5-glucoside was characterized from the bark of Crataeva religiosa together with other known compounds. - Key Word Index: Crataeva religiosa; Capparidaceae; flavan-3-ols; (-)-epiafzelechin 5-O-β-D-glucoside.
