Ethyl catechol

A pure culture of the organism was inoculated into a basal medium with the addition of 0.025% caffeic acid. After 7 days incubation at 25°C under conditions of reduced oxygen tension, the caffeic acid was completely metabolized. Metabolites of caffeic acid are identified as dihydrocaffeic acid and ethyl catechol, respectively. In the 1960s, it has been reported that a constitutive enzyme present in strains of Aerobacter decarboxylates caffeic acid to 4-vinylcatechol nonoxidatively [20], Several cinnamic acids have been tested and the decarboxylation product from /7-coumaric acid has been identified as 4-vinylphenol. Thus, the bacterial enzyme activity requires a relatively unhindered 4-hydroxy group on the aromatic ring and an acrylic acid side chain. 

METHOD 4 [115]-80% phenol in aqueous H2SO4 soiution of pH 3 is brought to 50 C. 30% H2O2 is then added causing an exothermic reaction and a temperature of 15 C over 3-4 minutes time. 6% aqueous H2SO3 is added after 4.5 minutes, the solution quickly cooled and extracted with isopropyl acetone (Strike would think that another solvent like methyl ethyl ketone could be used) to give 60% catechol. 

Both methyl aryl and methyl alkyl ethers are cleaved under these conditions. A methylenedioxy group, used to protect a catechol, is cleaved under similar conditions in satisfactory yield methyl and ethyl esters are stable (0-20°, 2 h). °... 

Waldmann et al. used tyrosinase which is obtained from Agaricus bisporus for the oxidation of phenols to give ortho-quinones via the corresponding catechols in the presence of oxygen (scheme 33).1881 A combination of this enzymatic-initiated domino process with a Diels-Alder reaction yields the functionalized bicyclic components 164 and 165 as a 33 1 mixture starting from simple p-methyl-phenol 160 in the presence of ethyl vinyl ether 163 as an electron rich dienophile via the intermediates 161 and 162 in an overall yield of 77%. 

Another series of complexes able to coordinate reversibly dioxygen is constituted by the derivatives [M(triphos)(catecholate)]+ illustrated in Scheme 4 (M = Co(III), Rh(III), Ir(III) triphos = MeC(CH2PPh2)3 catecholate = 9,10-dihydroxyphenantrene, di-/er/-butyl-catecholate, 3,4, 5,6-tetrachloro-catecholate, 4-methyl-catecholate, ethyl-3,4-dihydroxy-benzoate and 1,2-dihydroxynaphthalene).23... 

Methamidophos, see Acephate Methane, see Acetaldehyde, Benzoic acid, 7 Bromobenzoic acid. 3-Bromobenzoic acid. 4-Bromobenzoic acid. Bromoform, Carbatyl, Catechol, 2-Chlorobenzoic acid. 3-Chlorobenzoic acid. Chloroform, Dibromochloromethane, 2,5-Dichlorobenzoic acid. 1,2-Dichloroethane, Ethylamine, Ethyl bromide. Ethylene dibromide, Ethylenimine, Formic acid, Hydroqninone, 4 Hvdroxvbenzoic acid. Indole, 2-Iodobenzoic acid. 3 lodobenzoic acid. Methyl bromide, 4-Iodobenzoic acid. 2-Methylphenol, 4-Methylphenol, Phenol, Prorocatechuic acid. Svringic acid. Svringaldehvde. TCDD, Tetrachloroethylene, Toluene, Trichloroethylene, Vanillin. Vanillic acid. Vinyl chloride... 

The preparation of dibenzo-18-crown-6 polyether directly from catechol and bis(2-chloroethyl) ether has been reported previously. The present procedure is an improvement of this method. Although dibenzo-18-crown-6 polyether can be obtained in 80% yield from bis-[2-(o-hydroxyphenoxy)-ethyl] ether and bis(2-chloroethyl) ether, the former intermediate has to be synthesized by a method involving several steps. One of the hydroxyl groups of catechol must be protected against alkali by reaction with a molecule of dihydropyran or chloromethylm ethyl ether. Then the intermediate is treated with bis(2-chloroethyl) ether in the presence of alkali and, finally, converted into the desired intermediate by acid hydrolysis. The yield of bis[2-(o-hydroxyphenoxy)-ethyl] ether was less than 40% so that the overall yield of dibenzo-18-crown-6 polyether never approached 39-48%, the yield of the present direct method. 

Other Proteins The ouabain-binding site on (Na /K -adenosine-5 -triphosphatase, 46, 523 penicillin isocyanates for /3-lactamase, 46, 531 active site-directed addition of a small group to an enzyme the ethylation of ludferin, 46, 537 mandelate racemase, 46, 541 d imethylpyrazole carboxamidine and related derivatives, 46, 548 labeling of catechol O-methyltransferase with N-haloace-tyl derivatives, 46, 554 affinity labeling of binding sites in proteins by sensitized photooxidation, 46, 561 bromocolchicine as a iabei for tubuiin, 46, 567. 

From this work it is evident, then, that the hydrolysis of glycol lignin with sodium hydroxide does yield a rather significant amount of catechol and its methyl and ethyl derivatives. A maximum quantity of these, which amounted to 9% of the original lignin, was obtained at the conditions cited above. 

N 21-54% orn-colored ndls + % H2O (from dil ale), mp - explodes violently at 169-72° readily sol in glacial acet ac, chlf 8c ethyl acet sol in warm alkalies, giving a blue-red soln si sol in acet 8c benz was prepd by diazotizing either 5-nitro-3-amino be nzopyro-catechol-l-methyl ether or 2-bromo-5-nitro-3-aminoanisole (Refs 1, 2 Sc 3)... 

Okazaki, S., Hoshiya, T., Takahashi, S., Futakuchi, M., Saito, K. Hirose, M. (1993) Modification of hepato-and renal carcinogenesis by catechol and its isomers in rats pretreated with V-ethyl-V-hydroxyethylnitrosamine. Teratog. Carcinog. Mutag., 13, 127-137... 

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