92279-06-6Relevant academic research and scientific papers
Formation of strecker aldehydes from polyphenol-derived quinones and α-amino acids in a nonenzymic model system
Rizzi, George P.
, p. 1893 - 1897 (2006)
Fruits and vegetables contain naturally occurring polyphenolic compounds that can undergo enzyme-catalyzed oxidation during food preparation. Many of these compounds contain catechol (1,2-dihydroxybenzene) moieties that may be transformed into o-quinone d
Methyl p-coumarate, a melanin formation inhibitor in B16 mouse melanoma cells
Kubo, Isao,Nihei, Ken-Ichi,Tsujimoto, Kazuo
, p. 5349 - 5354 (2004)
p-Coumaric acid and methyl p-coumarate inhibit the oxidation of l-tyrosine catalyzed by mushroom tyrosinase. However, both were oxidized as monophenol substrate analogues at an extremely slow rate. Methyl p-coumarate significantly suppressed the melanin formation in B16 mouse melanoma cells, whereas p-coumaric acid did not show this activity. p-Coumaric acid (4-hydroxycinnamic acid) and methyl p-coumarate (methyl 4-hydroxycinnamate) inhibit the oxidation of l-tyrosine catalyzed by mushroom tyrosinase. However, both were oxidized as monophenol substrate analogues at an extremely slow rate. This oxidation was significantly accelerated as soon as catalytic amounts (0.01 mM) of l-3,4-dihydroxyphenylalanine (l-DOPA) became available as a co-factor. Methyl p-coumarate significantly suppressed the melanin formation in B16 mouse melanoma cells, whereas p-coumaric acid did not show this activity.
Degradation of cyanidin 3-glucoside by caffeic acid o-quinone. Determination of the stoichiometry and characterization of the degradation products
Kader, Farid,Irmouli, Mohammed,Zitouni, Nedjma,Nicolas, Jean-Pierre,Metche, Maurice
, p. 4625 - 4630 (1999)
Caffeic acid o-quinone (CQ) was prepared by oxidation of caffeic acid with o-chloranil in organic media. The reaction between the purified CQ and cyanidin 3-glucoside (Cy 3-glc, o-diphenolic anthocyanin) was monitored by HPLC, and quantitative analyses we
Stable isotope-labeling studies on the oxidative coupling of caffeic acid via o-quinone
Tazaki, Hiroyuki,Taguchi, Daisuke,Hayashida, Takaomi,Nabeta, Kensuke
, p. 2613 - 2621 (2007/10/03)
The formation of ortho-quinone from ortho-diphenol is a key step in its dimerization. An NMR analysis of the oxidation of 3,4-dihydroxycinnamic acid (caffeic acid) by NaIO4 revealed the formation of 3-(3′ ,4′-dioxo-1′ ,5′-cyclohexadienyl) prope
A defense Mechanism against Pathogenic Bacteria in the Digestive Tracts of Silkworm Larvae-in vitro Evidence of the Formation of Caffeoquinone, a True Antibacterial Substance, and Synergism of Amino Compounds
Nakano, Hidenori,Tahara, Satoshi,Iizuka, Toshihiko,Mizutani, Junya
, p. 549 - 556 (2007/10/02)
For the defense mechanism against pathogenic bacteria in the digestive tracts of silkworm larvae reared on mulberry leaves, in vitro evidence of the formation of atrue antibacterial substance was obtained. caffeic acid (CA) derived from chlorogenic acid (ChA)was converted into caffeoquinone (CQ) by base-catalyzed oxidation in a buffer solution (pH 10.0).CQ was trapped as 6'phenylsulfonylcaffeic acid (6'sulfone) by the addition of benzenesulfinic acid (BSA).The synergetic effects of amino compounds on the antibacterial activity of CQ are discussed in detail, and the probable reactions of CA with amino and thiol compounds in the alkaline solution are proposed.
TRAPPING OF DOPACHROME WITH 2,3-DIHYDRO-1H-CYCLOPENTINDOLE
Omote, Yoshimori,Tomotake, Atsushi,Kashima, Choji
, p. 2993 - 2994 (2007/10/02)
Dopachrome (6) and related o-benzoquinones including dopaquinone (2d) were trapped, by treating each quinone from the corresponding catechol, with 2,3-dihydro-1H-cyclopent-indole (3) to afford -propellane adduct.
