1,2,3 - Trihydroxybenzene

The synthesis of 2,4-dihydroxyacetophenone [89-84-9] (21) by acylation reactions of resorcinol has been extensively studied. The reaction is performed using acetic anhydride (104), acetyl chloride (105), or acetic acid (106). The esterification of resorcinol by acetic anhydride followed by the isomerization of the diacetate intermediate has also been described in the presence of zinc chloride (107). Alkylation of resorcinol can be carried out using ethers (108), olefins (109), or alcohols (110). The catalysts which are generally used include sulfuric acid, phosphoric and polyphosphoric acids, acidic resins, or aluminum and iron derivatives. 2-Chlororesorcinol [6201-65-1] (22) is obtained by a sulfonation—chloration—desulfonation technique (111). 1,2,4-Trihydroxybenzene [533-73-3] (23) is obtained by hydroxylation of resorcinol using hydrogen peroxide (112) or peracids (113). 

Neither the mechanism by which benzene damages bone marrow nor its role in the leukemia process are well understood. It is generally beheved that the toxic factor(s) is a metaboHte of benzene (107). Benzene is oxidized in the fiver to phenol [108-95-2] as the primary metabolite with hydroquinone [123-31-9] catechol [120-80-9] muconic acid [505-70-4] and 1,2,4-trihydroxybenzene [533-73-3] as significant secondary metabolites (108). Although the identity of the actual toxic metabolite or combination of metabolites responsible for the hematological abnormalities is not known, evidence suggests that benzene oxide, hydroquinone, benzoquinone, or muconic acid derivatives are possibly the ultimate carcinogenic species (96,103,107—112). 

Rieble S, DK Joshi, MH Gold (1994) Purification and characterization of a 1,2,4-trihydroxybenzene... 

Dioxygenase. Although it is not involved in the transformation of PAHs, it may be noted for the sake of completeness that a catechol intradiol dioxygenase is involved in the fission of 1,2,4-trihydroxybenzene that is formed from a number of aromatic substrates (Rieble et al. 1994). 

The degradation of resorcinol can take place by several pathways that are initiated by hydroxylation. 1,2,4-Trihydroxybenzene is degraded by (a) 1 2 dioxygenation and... 

Reichenbecher WW, B Schink (1997) Desulfovibrio inopinatus sp nov, a new sulfate-reducing bacterium that degrades hydroxyhydroquinone (1,2,4-trihydroxybenzene). Arch Microbiol 168 338-344. 

The metabolism of pentafluoro-, pentachloro-, and pentabromophenol by Mycobacterium fortuitum strain CG-2 is initiated by a monooxygenase that carries out hydroxylation at the para position (Uotila et al. 1992). Cell extracts of Rhodococcus chiorophenoiicus Mycobacterium chlorophenolicunt) strain PCP-1 in the presence of a reductant transformed tetrafluoro-, tetrachloro-, and tetrabromohydroquinone to 1,2,4-trihydroxybenzene by reactions that clearly involve both hydrolytic and reductive loss of fluorine (Uotila et al. 1995). 

The blue dye (47), formed from the autoxidation of 4-/V,TV-di methyl-amino-2-hydroxyaniline, is the oxygen analogue of methylene blue. The autoxidation of 1,2,4-trihydroxybenzene, carried out in the presence of ammonia, gives the hydroxyphenoxazinone dye (48) via a 2,4-dihydroxyani-line intermediate (Scheme 17). Many types of phenoxazines, phenazines, and phenoxazinium salts can be obtained by autoxidation of polyhydroxyben-zenes and their amino derivatives. Some autoxidative dyes may give poly-... 

The synthesis of 2-hydroxyphenazine (9) caused unexpected problems, though. The resultant yield of 9 was very low with both the condensation of 2-hydroxy-1,4-benzoquinone (33) [30], available from 1,2,4-trihydroxybenzene... 

Hydroxyhydroquinone (24) forms colorless plates from diethyl ether when freshly prepared. It occurs in many plants and trees in the form of ethers, quinonoid pigments, coumarin derivatives, and complex compounds. Sponges from the coastal waters of Florida have been found to contain small amounts of 1,2,4-trihydroxybenzene and traces of 2,2, 4,4, 6,6 -hexahydroxybiplienyl (25) (78). The benzenetriol has also been isolated from tobacco leaves and tar from tobacco smoke (79). Hydroxyhydroquinone has strong reducing properties. Applications have been suggested in the synthesis of agricultural... 

In a study by Orzechowski et al. (1995), hepatocytes from adult male Wistar rats and NMRI mice were incubated for 1 hour with 0.5 mM 14C-benzene, and the supernatant analyzed for metabolites. Formation of sulfate conjugates of benzene, hydroquinone, and 1,2,4-benzenetriol was also studied in a separate experiment. Mouse hepatocytes produced two metabolites (1,2,4-trihydroxybenzene sulfate and hydroquinone sulfate) that were not found in rat hepatocyte incubations. These sulfate metabolites were found in incubations including benzene, or the metabolites themselves, hydroquinone and 1,2,4-benzenetriol. Mouse hepatocytes were almost three times more effective in metabolizing benzene, compared to rat hepatocytes. This difference was accounted for in the formation of hydroquinone, hydroquinone sulfate, and 1,2,4-trihydroxybenzene sulfate. These in vitro experiments indicate there are both quantitative and qualitative differences in rodent metabolism of benzene. 

Phenol, hydroquinone, catechol, benzoquinone, and 1,2,4-trihydroxybenzene form adducts in bone marrow mitochondria, resulting in the inhibition of the synthesis of mitochondrial proteins that are necessary for mitochondrial function (Kalf et al. 1982). 

HydroxylatUm of resorcinol ethers Methyl or THP ethers of resorcinol are oxidized regioselectively by w-chloroperbenzoic acid in CH2CI2 at 0° to derivatives of 1,2,4-trihydroxybenzene in yields of 55-80%. 

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