Simple phenolic compounds structure

Tenerife and La Palma, revealed the existence of luteolin and an array of simple phenolic derivatives as well as three known phytosterols, B-amyrin, sitosterol, and stigmasterol. The phenols identified comprised a set of phenylpropanoids myristicin [566] (see Fig. 6.16 for structures 566-573), methyleugenol [567], todadiol [568], todatriol [569], crocatone [570], elemicin [571], apiole [572], and the coumarin scopoletin [573]. The occurrence of these compounds is recorded in Table 6.5. The differences between the two profiles were taken by Gonzalez and his co-workers... 

Many excellent discussions of natural occurrence, structure, characterization, and analysis of phenolic compounds are available in the literature, and a series of books devoted to flavonoid chemistry has also been published. Detailed discussions on various chromatographic modes, including HPLC, GC, column chromatography (CC), capillary electrophoresis (CE), PC, and TLC, of simple phenolics and polyphenols are also presented in the recent book, Handbook of Food Analysis, volume 1, edited by Nollet (1). Due to their diversity and the chemical complexity of phenolic compounds, this chapter is limited to phenolic compounds that are considered to be important to foods and the food industry. 

Breaking of complex structures Production of energy products or simple chemicals for example, lignin can be used for the synthesis of phenolic compounds upon hydrolytic treatment... 

Phenolic compounds constitute one of the most numerous and widely distributed groups of phytochemicals in the plant kingdom. More than 8000 phenolic compounds have been described and this list continues to expand.49 Phenolic compounds exist as simple molecules, such as the phenolic acids, to highly polymerized structures, such as the proanthocyanidins. Harbome48 classified phenolics into 10 subclasses based upon their chemical structure these subclasses include the simple phenolics, phenolic acids, hydroxycinnamic acids, and flavonoids, among others. The flavonols represent one of the most commonly distributed classes of flavonoid compounds. 

In the NE reaction, lignin is degraded by boron trifluoride in the presence of excess phenol. The key step in this process is the dealkylation of DPM-type structural units formed by phenolation the Ca side chain position of the phenylpropane units. To bring this reaction sequence into clear focus, it is appropriate to discuss the alkylation and dealkylation of simple aromatic compounds. 

A method developed by Adler et al. (1958) is based on the oxidation of simple phenolic guaiacyl (Adler and Hernestam 1955) or syringyl (Chang et al. 1975) compounds with aqueous sodium periodate solution to ortho-quinone structures in which process nearly lmol of methanol per mol of phenolic hydroxyl group is released [Eq. (1)]. 

The phenolics of grapes and berry fruits constitute a large group of compounds with various structural complexities. Thus, total phenolics encompass the more simple phenolic acids along with the various classes of flavonoids, some occurring... 

Many concurrent reactions are usually operative. Their relative importance depends on the structure of the resins and the type of curing agent. The degradation products are mostly phenolic compounds. Three mechanisms based on the principle of simple ether cleavage and on the experimental results obtained were proposed ... 

Phenolics and their functional derivatives are widely found throughout the plant kingdom. One defining characteristic of these compounds is that their aromatic ring usually contains at least one hydroxyl substituent. In a broad sense, phenolics, which are classified according to their structural skeleton, are basically derivatives from simple phenols and phenolic acids, phenylpropanoids including coumarins and lignans, flavonoids and related compounds, and stilbenes. Some of these compounds which show anti-inflammatory activity are reviewed in this section. 

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