3,5-Dihydroxycinnamic acid

On the basis of the obtained results and the literature[17-18], we assume that during the oxidative decomposition of p-coumaric acid 1, three kind of reaction can happen before the opening of the aromatic ring (Scheme 1) cleavage of the very reactive exocyclic double bond to give p-hydroxybenzaldehyde 2, hydroxylation of the aromatic ring to yield 3,4-dihydroxycinnamic acid 3 and oxidation of aldehydes to carboxylic acids such as oxidation of 2 to p-hydroxybenzoic acid 4. Compound 2 can be hydroxylated to yield 3,4- dihydroxybenzaldehyde 6. and Compound 4 can also be hydroxylated to yield 3,4-dihydroxybenzoic acid 5. 

Coumaric acid (or 4-hydroxycinnamic acid) R = H Caffeic acid (or 3,4-dihydroxycinnamic acid) R = OH Cinnamaldehyde... 

Ananas comosus (L.) Merrill China Ergosterol peroxide, ananasic acid, 5-stigmautena-3(3,7d-diol, 3,4-dihydroxycinnamic acid, 4-hydroxycinnamic acid, bromelin, vitamins.57 Antioxdant activity, for digestion, lower blood pressure, anticancer. 

The most common cinnamic acids are caffeic (3,4-dihydroxycinnamic acid), ferulic (3-methoxy-4-hydroxy), sinapic (3,5-dimethoxy-4-hydroxy) and p-coumaric (4-hydroxy) acid, Table 4 [13]. 

The phenolic acids of interest here [caffeic acid (3,4-dihydroxycinnamic acid), ferulic acid (4-hydroxy-3-methoxycinnamic acid), p-coumaric acid (p-hydroxycinnamic acid), protocatechuic acid (3,4-dihydroxybenzoic acid), sinapic acid (3,5-dimethoxy-4-hydroxyxinnamic acid), p-hydroxybenzoic acid, syringic acid (4-hydroxy-3,5-methoxybenzoic acid), and vanillic acid (4-hydroxy-3-methoxybenzoic acid)] (Fig. 3.1) all have been identified as potential allelopathic agents.8,32,34 The primary allelopathic effects of these phenolic acids on plant processes are phytotoxic (i.e., inhibitory) they reduce hydraulic conductivity and net nutrient uptake by roots.1 Reduced rates of photosynthesis and carbon allocation to roots, increased abscisic acid levels, and reduced rates of transpiration and leaf expansion appear to be secondary effects. Most of these effects, however, are readily reversible once phenolic acids have been depleted from the rhizosphere and rhizoplane.4,6 Finally, soil solution concentrations of... 

Synonyms 3,4-Dihydroxycinnamic acid 3,4-Dihydroxybenzeneacrylic acid Source Murga, R. Sanz, M.T. Beltran,S. ... 

The structure was proved by synthesis of a reference sample obtained by catalytic hydrogenation of dihydroxystyrene, itself prepared by decarboxylation of 3,4-dihydroxycinnamic acid (caffeic acid) according to Reichstein (1932). 

From the results of a study in which Kentucky reference IRl cigarettes were spiked with increasing levels of chlorogenic acid (the 3-ester of 3,4-dihydroxycinnamic acid with... 

The ability of oxidation products of 3,4-dihydroxycinnamic acid to prevent the binding of TSH to human... 

Auf mkolk M, Amir SM, Kubota K, et al. The active principles of plant extracts with antithyrotropic activity oxidation products of derivatives of 3,4-dihydroxycinnamic acid. Endocrinology 1985 116 1677-1686. 

As p-hydroxy-cinnamic acid can exist in either the or trans configuration, both were tested. The data (Table III) showed that the -isomer was more active than the trans-isomer. Saturation of the double bond in the aliphatic portion of the molecule was investigated by testing the dihydro-derivatives of p-hydroxycinnamic and 3,4-dihydroxycinnamic acids. The dihydro-acids were slightly more active than the corresponding cinnamic compounds. 

Dihydroxycinnamic acid 2-ester with 3-(3,4-dihydroxyphenyl) lactic acid R-(+)-2-(3,4-Dihydroxycinnamoyloxy)-3-(3,4-dihydroxyphenyl) propionic acid. See Rosmarinic acid... 

Synonyms Benzenepropanoic acid, a-[[3-(3,4-dihydroxyphenyl)-1 -oxo-2-propenyl] oxy]-3,4-dihydroxy- Benzenepropanoic acid, o-[[(3,4-dihydroxyphenyl)-1 -oxo-2-propenyl] oxy]-3,4-dihydroxy- Cinnamic acid, 3,4-dihydroxy-, 2-ester with 3-(3,4-dihydroxyphenyl) lactic acid 3,4-Dihydroxycinnamic acid 2-ester with 3-(3,4-dihydroxyphenyl) lactic acid R-(+)-2-(3,4-Dihydroxycinnamoyloxy)-3-(3,4-dihydroxyphenyl) propionic acid a-[[(3,4-Dihydroxyphenyl)-1-oxo-2-propenyl] oxy]-3,4-dihydroxybenzenepropanoic acid Rosemary acid Rosmarinate Classification Naturally occurring polyphenolic compd. 

Caffeic acid (3,4-dihydroxycinnamic acid) is a widespread phenolic acid with a well-known antioxidant activity (Nardini et al. 1995, Vieira et al. 1998). In human monocytic U937 cells it inhibited both ceramide-induced NF-xB binding activity and apoptosis at (imolar concentrations (Nardini et al. 2001). Other antioxidants were totally ineffective in inhibiting apoptosis, although affecting NF-xB activation. Caffeic acid was found to inhibit protein tyrosine kinase activity, suggesting that this mechanism can be on the basis of the inhibition of apoptosis. 

A novel one-pot two-step pathway for the synthesis of 5-vinylbenzo[Anodic oxidation of 6 in the presence of 2,6-lutidine and lithium perchlorate gave a mixture of dioxole 7 and side product 8, which could be converted entirely into 7 upon treatment with p-toluenesulfonic acid (13AGE12865). Boron trifluoride-promoted cycloaddition of P-methoxyvinyl sulfides to... 

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