Gallic acid 3,4,5-Trihydroxybenzoic

Gallic acid (3,4,5-Trihydroxybenzoic acid) +0.5 (calomel) glassy carbon 268... 

Whistles, Pyrotechnic. US projectile ground-burst and booby-trap flash simulators precede their flash and expin with a whistling sound. The fact that certain compns whistle when compressed into a tube and ignited has been used in the fireworks industry for many years. The active substance most often used in pyrot whistles is gallic acid (3,4,5-trihydroxybenzoic acid). The K salts of benzoic acid of 2,4-dinitrophenol and of picric acid (2,4,6-trinitrophenol) and the Na salt of salicylic acid (o-hydroxybenzoic acid) are also effective. They are combined with K chlorate,... 

Gallic acid (= 3,4,5-Trihydroxybenzoic acid) (phenolic acid) Widespread basic constituent of the hydrolysable tannins (gallotannins) Mangifera indica (Anacardiaceae) PEP (487 pM) [115]... 

Antiseptic plant-derived phenols include phenol (Phe-OH, hydroxybenzene, carbolic acid), />-cresol (4-methylphenol), catechol (1,2-dihydroxybenzene), resorcinol (1,3-dihydroxybenzene) and pyrogallol (1,2,3-trihydroxybenzene). Other simple phenols with antimicrobial properties include some related to benzoic acid (benzenecarboxylic acid), namely salicylic acid (2-hydroxybenzoic acid), ginkgoic acid (2-hydroxy-6-(pentadec-8-enyl)benzoic acid), gentisic acid (2,5-dihydroxybenzoic acid), pyrocatechuic acid (3,4-dihydroxybenzoic acid) and gallic acid (3,4,5-trihydroxybenzoic acid). Other plant-derived phenol-related compounds include 4-methylcatechol, 1,3-dihydroxy-5-(heptadec-12-enyl)benzene, hydroquinone (1,4-dihy-droxybenzene), 1,4-dihydroxy-2-geranyl (di-isoprenyl)benzene and 4-methoxybenzaldehyde (/>-anisealdehyde). 

Ellagic acid is the dilactone of the dimer of gallic acid (3,4,5-trihydroxybenzoic acid). The biosynthesis of ellagic acid (XVH) in plants occurs via an one-electron oxidation of gallic acid (XVHI) followed by dimerization of the gallic acid radicals, and then proceeds by stabilization... 

Simple benzoic acids are synthesized in plants via the shikimate pathway, which is derived from shikimic acid, which is itself derived from quinic acid via 3-dehydroquinic and 3-dehydroshikimic acids (Scheme 68.1). In fact, shikimic, but not quinic, acid has been described in the leaves and stems of this species [14]. The simplest benzoic acids are protocatechuic acid (3,4-dihydroxybenzoic acid) and gallic acid (3,4,5-trihydroxybenzoic acid). The latter proved to be present in the tissues of C. roseus, in addition to vanillic acid (4-hydroxy-3-methoxybenzoic acid) [15]. The quantitative composition of C. roseus in benzoic acids can be seen in Table 68.1, and the structures of these compounds are represented in Fig. 68.1. 

Equally, compounds are available which retard plant growth. Again both naturally-occurring and a variety of synthetic compounds exist. Examples of the naturally occurring group are gallic acid (3,4,5-trihydroxybenzoic acid) and cinnamic acid, both of which prevent sprouting in stored onions and potatoes. 

The hydroxybenzoic acids that are found in various fruits and occur mostly as esters include salicylic acid (2-hydroxybenzoic acid), 4-hydroxybenzoic acid, gentisic acid (2,4-di-hydroxybenzoic acid), protocatechuic acid (3,4-dihydroxybenzoic acid), gallic acid (3,4,5-trihydroxybenzoic acid), vanillic acid (3-methoxy-4-hydroxybenzoic acid) and ellagic acid (IX, Formula 18.13), the dilactone of hexahydroxydiphenic acid (Table 18.19). Table 18.19 shows the most important sources of 4-hydroxybenzoic acid, protocatechuic acid and gallic acid. Strawberries (0.2-0.5), raspberries (1.2) and blackberries (1.9-2.0) contain higher concentrations of free and bound ellagic acid (g/kg). 

Gallic acid (3,4,5-trihydroxybenzoic acid) can be formed by acid hydrolysis of hydrolyzable tannins. Differences among the ester derivatives are only in the number of carbon atoms in the aliphatic side-chain. These differences confer different physicochemical characteristics, especially in lipophilicity evaluated by the value of partition coefficient (C log P). Chemical modifications in the gallic acid molecule can alter the pharmacokinetic and pharmacodynamic properties, such as changing the solubility and the degree of ionization. The names of the compounds are abbreviated according to the length of the side-chain (Locatelli et al., 2013). 

Tannic acid is generally extracted from the galls by a mixture of solvents involving water, alcohol, ether, and acetone. The complex tannic acid is separated from the simple acids such as gallic acid (3,4,5-trihydroxybenzoic acid) and is then purified. 

Gallic Acid 3,4,5-Trihydroxybenzoic Acid 25167-82-2 Chlorophenol Trichlorophenol... 

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