Cinnamic acid derivatives and

The chemical formulae for a variety of plant phenols are given in Fig. 16.2, including examples of simpler phenols, such as cinnamic acid derivative, and of tocopherols, flavonoids, flavonoid glycosides and anthocyanidins. The flavonoids include the following subclasses flavanones (taxifolin), flavones (luteolin), flavonols (quercetin) and flavanols (catechin/epicatechin). The... 

Lignin has a complex structure that varies with the source, growing conditions, etc. This complex and varied structure is typical of many plant-derived macromolecules. Lignin is generally considered as being formed from three different phenylpropanoid alcohols— coniferyl, coumaryl, and sinapyl alcohols, which are synthesized from phenylalanine via various cinnamic acid derivatives and commercially is sometimes treated as being composed of a Cg repeat unit where the superstructure contains aromatic and aliphatic alcohols and ethers, and aliphatic aldehydes and vinyl units. 

Houpis, I.N., Patterson, L.E., Alt, C.A., Rizzo, J.R., Zhang, T.Y. and Haurez, M. S3mthesis of PPAR Agonist via Asymmetric Hydrogenation of a Cinnamic Acid derivative and Stereo-specific Displacement of (S)-2-Chloropropionic Acid. Org. Lett. 2005, 7, 1947-1950. 

Cinoiazepam [inn] is one of the [1,41 benzodiazepines, a BENZODIAZEPINE BINDING-SITE AGONIST, with most of its properties similar to diazepam. It has HYPNOTIC, ANTICONVULSANT and ANXIOLYTIC activity. It has been used orally to treat insomnia and anxiety, cinoxacin [ban, inn, jan, usan] (Clnobac ) is an ANTIMICROBIAL, One of a 4-quinolone family related to nalidixic acid, which, though symthetic, are sometimes described as ANTIBIOTICS. It can be used clinically as an ANTIBACTERIAL, mainly used orally for gut infections. Cinoxate [inn, usan] is a cinnamic acid derivative and can be used in topical sunscreen preparations. 

In TFA solution, electron-rich examples of cinnamic acid derivatives and phenols give high yields of 4-aryl-3,4-dihydrocoumarins at room temperature with good regioselectivity <05JOC2881,05T9291>. 

Apparently, the quality of cleavage planes (Sections 2.1.7 and 2.1.8) plays its role here and it is to be assumed that a slope limit might be found between 32 and 48° for these typical examples, as we start with almost flat molecules in both 64 b and 65 b. Clearly, more examples have to be analyzed in order to definitely assess the borderline. Unfortunately, most of the early claims with cinnamic acid derivatives and their so-called a-, -, and -/-structures were not substantiated with published X-ray data and these were not available upon request. Finally, the steepness of molecules on cleavage planes is less important for Z —y E isomerizations (Section 2.1.5). It should therefore be checked whether 65 b undergoes as yet undetected solid-state photoisomerization at a suitable wavelength to give 64 b. 

The phenolic compounds present in these three commodities fall into two general classifications, cinnamic acid derivatives and flavonoids. Included in the former are chlorogenic acid and its isomers, free cinnamic acids such as caffeic and p-coumaric acid and various esters of those two acids. Included among the flavonoids are the following ... 

The main classes of phenolic compounds found in fruits are (1) phenolic acids, (2) stilbenes, (3) lignans, (4) flavonoids, and (5) tannins or proanthocyanidins. These classes are the most abundantly occurring phenolic compounds which are also an integral part of everyday dietary antioxidants in populations worldwide [7]. The most abundant phenolic compounds in the diet are phenolic acids (benzoic and cinnamic acid derivatives) and flavonoids which account for 60% and 30%, respectively, of total dietary phenolic compounds [7]. These phenolic compounds may be associated with various carbohydrates and organic acids and with one another (Figure 2 Table 1). 

Benzoic and cinnamic acid derivatives and flavonoids are the two most distributed phenolics within plants. Polyphenolic units are biosynthesized via shikimate pathway, resulting in cinnamic acids C -C phenylpropanoid building block that also contributes to other plant phenolics backbones such as those from flavonoids (Q-Ca-Ce), anthocyanidins (C6-C3-C6), and coumarins (C6-C3). Stilbeneoids (C6-C2-C6) and benzoic acid derivatives (Cfi-Ci) such as gallic and ellagic acids are also synthesized through this metabolic pathway (Fig. 1). 

From a number of plant tissues PAL has been extracted in two different forms (3-6). The results of end product inhibitor studies with these enzymes by different workers have been summarized by Ranjeva, Boudet and Alibert (7) In all cases a differential inhibition of a particular enzyme by benzoic acid derivatives and cinnamic acid derivatives was observed. Some were inhibited more by the former compounds, others more by the latter. This has been interpreted as evidence that the different PAL isoenzymes are part of different pathways, one leading to cinnamic acid derivatives and the other to benzoic acid derivatives. 

Aromatic biosynthesis, aromatizatioa biosynthesis of compounds containing the benzene ring system. The most important mechanisms are 1. the shi-kimate/chorismate pathway, in which the aromatic amino acids, L-phenylalanine, L-tyrosine and L-trypto-phan, 4-hydroxybenzoic acid (precursor of ubiquinone), 4-aminobenzoie acid (precursor of folic acid) and the phenylpropanes, including components of lignin, cinnamic acid derivatives and flavonoids are synthesized and 2. the polyketide pathway (see Polyke-tides) in which acetate molecules are condensed and aromatic compounds (e.g. 6-methylsalicylic acid) are synthesized via poly-fl-keto acids. Biosynthesis of flavonoids (e.g. anthocyanidins) can occur by either pathway. 

The phenomenon of catalytic facilitation is also shown by membrane-bound multienzyme systems involved in the formation of cinnamic acid derivatives and cyanogenic glycosides (Table 3). The proximity of these enzymes in or on membranes favors transformation of internally produced intermediates even if these compounds are not covalently bound. 

A special group of polyketides (D 3.3) is formed from the CoA-esters of cinnamic acid derivatives and one, two, or three molecules of malonate. 

Pro 4 Very rapid irreversible sorption occurs on initial addition of high concentrations of phenolic acids to soil subsequently, however, sorption is very slow for cinnamic acid derivatives and almost non-existent for benzoic acid derivatives. For soil systems with continuous production of phenolic acids a semi-steady state will occur and irreversible sorption will thus be very small. That phenolic acids and soils can potentially reach a steady state has been demonstrated in the continuous-flow system. 

The labelling sites of decodine 6.49) and decinine 6.50) formed from [2- " C]lysine [as (. /7)] were C-5 and C-9. This locates ring A as being derived from this amino acid. Ring D plus attached C3 unit [see especially 6.48) corresponds to a cinnamic acid derivative, and it has been shown that this fragment derives from phenylalanine, a... 

We examined the epoxidation of carbon-carbon double bonds by oxygen atom transfer reactants. We used the competition between cinnamic acid derivatives and crotonic acid in water (D2O) and water with added 2-propanol. There was no selectivity when the oxidant... 

Adisakwattana, S., Chantarasinlapin, P., Thammarat, H. and Yibchok-Amm, S., 2009. A series of cinnamic acid derivatives and their inhibitory activity on intestinal a-glucosidase. Journal of Enzymelnhihition and Medicinal Chemistry 24 5), 1194-1200. 

A large number of inhibitors of DOPA decarboxylase have been described a few of the most imtent compounds are listed in Table 7. Inhibitors include DOPA analogues such as a-methylDOPA. cinnamic acid derivatives and hydrazino compounds. Although many of these compounds are effective inhibitors of the enzyme in vivo, there is such a Mgh DOPA-decarboxylase activity in most tissues that it has proved very difficult to produce any significant inhibition of catechohunine bio-... 

Simonyan, A. V. (1993). Activity of cinnamic acid derivatives and new methods for their synthesis (review). Pharmaceutical Chemistry Journal, 27(2), 92. 

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