Structure of catechinic acid. Base rearrangement product of catechin

Sears, Karl D.; Casebier, R. L.; Hergert, H. L.; Stout, George H.; McCandlish, L. E.

doi:10.1021/jo00936a015

Cited by 64 publications

(41 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…12(a)) showed the presence of high amounts of epigallocatechin (12) as reported by Nagle et al [39] and Graham [40] as the major catechin found in green tea. Also, similar to the findings of Chen et al [41] epicatechin (10) was the second most abundant flavan-3-ol in green tea. Also, in Fig.…”

Section: Tea Leavessupporting

confidence: 89%

“…Another remarkable result of the THM-GC-MS of catechin (trans epimer) and epicatechin (cis epimer) was the large retention time difference between partially methylated catechin (8) and epicatechin (10). On THM of epicatechin product 10 (not shown) was the dominant peak in the chromatogram, thus, this paper has shown that one can discriminate between epicatechin and catechin using the THM approach of analysis.…”

Section: Thm-gc-ms Of Catechin and Epicatechinmentioning

confidence: 74%

“…under basic conditions [8][9][10] or as a result of photo-isomerization [11]. Several compounds were isolated in a base-catalyzed reaction of catechin and epicatechin at high pH and different temperatures.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Analysis of catechins and condensed tannins by thermally assisted hydrolysis/methylation-GC/MS and by a novel two step methylation

Shadkami

Estévez

Helleur

2009

Journal of Analytical and Applied Pyrolysis

View full text Add to dashboard Cite

Section: Tea Leavessupporting

confidence: 89%

Section: Thm-gc-ms Of Catechin and Epicatechinmentioning

confidence: 74%

See 1 more Smart Citation

Analysis of catechins and condensed tannins by thermally assisted hydrolysis/methylation-GC/MS and by a novel two step methylation

Shadkami

Estévez

Helleur

2009

Journal of Analytical and Applied Pyrolysis

View full text Add to dashboard Cite

“…Rearrangement products of catechins have also been held responsible for the inhibition of collagen breakdown by collagenases in vitro [32]. Three candidates for active rearrangement products are (+)-epicatechin [12], catechinic acid [27], and quinones.…”

Section: Discussionmentioning

confidence: 99%

Effect of catechins and citrus flavonoids on invasionin vitro

et al. 1991

View full text Add to dashboard Cite

Catechins, a group of flavonoid molecules, inhibit invasion of mouse MO4 cells into embryonic chick heart fragments in vitro. The anti-invasive effects can be ranked as follows: (+)-catechin greater than (-)-epicatechin greater than 3-O-methyl-(+)-catechin greater than 3-O-palmitoyl-(+)-catechin. Most of the catechins are unstable in cell culture media, and their spontaneous rearrangement products tend to bind to extracellular matrix (ECM). Due to these interactions proteases such as tissue-type plasminogen activator (t-PA) are linked to the ECM glycoprotein laminin. This leads to a partial inactivation of the enzyme. Within the group of catechins we found a positive correlation between anti-invasive activity and linking of t-PA to laminin. Citrus flavonoids are also anti-invasive in vitro (tangeretin greater than nobiletin greater than hesperidin = naringin). However, these stable molecules show poor affinity for ECM, and do not link enzymes to laminin. These data suggest that catechins and citrus flavonoids inhibit invasion in vitro by different mechanisms.

show abstract

“…The quinone methide intermediate is rather labile, and side reactions other than epimerization are thought to occur from this intermediate (Sears et al, 1974;Kennedy et al, 1984). Both epi type catechins and non-epi type catechins are also labile to dimerization (Roginsky et al, 2005), hydrolysis (Ito et al, 2003), oxidation and polymerization (Hatano et al, 2004).…”

Section: Epimerization Behavior Of Tea Catechins and The Effect Of β-Cdmentioning

confidence: 99%

Effect of Cyclodextrins on the Thermal Epimerization of Tea Catechins

Okumura

Ichitani

Takihara

et al. 2008

FSTR

View full text Add to dashboard Cite

The epimerization reaction of tea catechins was investigated at pH 5.5 and 120 °C in the absence/presence of cyclodextrins (CDs). In the absence of CDs, a considerable quantity (~20%) of products originating from reactions other than the epimerization ("other products") was formed during the epimerization of gallated catechins. In the case of (-)-EGCg, addition of β-CD to the reaction solution reduced the quantity of these other products to just a few percent, but other CDs with different cavity sizes had little effect. Generally, the addition of β-CD increased the ratio of non-epi type catechins, that is, [non-epi type catechin] / ([epi type catechin]+[non-epi type catechin]). Molecular orbital (MO) calculations using the PM3 method suggested that non-epi type catechins are more thermodynamically stable than their epitype counterparts, moving the equilibrium position in favor of non-epi type catechins in the epimerization process.

show abstract

Structure of catechinic acid. Base rearrangement product of catechin

Cited by 64 publications

References 0 publications

Analysis of catechins and condensed tannins by thermally assisted hydrolysis/methylation-GC/MS and by a novel two step methylation

Analysis of catechins and condensed tannins by thermally assisted hydrolysis/methylation-GC/MS and by a novel two step methylation

Effect of catechins and citrus flavonoids on invasionin vitro

Effect of Cyclodextrins on the Thermal Epimerization of Tea Catechins

Contact Info

Product

Resources

About