Pyrocatechine acid

Propylene Tetramer Propylene Tetramer Propylene Trimer Propyleneimine, Inhibited Propylethylene N-Propyl Mercaptan N-N-Propyl-L-Propanamine Prussic Acid Pseudohexyl Alcohol Pyrazine Hexahydride Pyridine Pyrocatechin Pyrocatechinic Acid Pyrocatechol Pyrocatechuic Acid Pyrofax... 

Pterocarya stenoptera DC Feng Yang (Wing nut) (stem, leaf, bark) Salicylic acid, kino-tannic acid, pyrocatechine acid, protocatechinic acid.48-60 Diuretic, used on wounds and ulcers, hemorrhage, suppuration. 

PYROCATECHINIC ACID (120-80-9) Combustible solid (flash point 260°F/127°C cc). Dust and powder can form explosive mixture with air. Violent reaction with strong oxidizers, nitric acid. Flow or agitation of substance may generate electrostatic charges due to low conductivity. 

CAS 120-80-9 EINECS/ELINCS 204-427-5 Synonyms 1,2-Benzenediol o-Benzenediol Catechol Cl 76500 1,2-Dihydroxybenzene o-Dihydroxybenzene o-Dioxybenzene o-Diphenol o-Hydroquinone 2-Hydroxyphenol o-Hydroxyphenol Oxyphenic acid o-Phenylenediol Pyrocatechin Pyrocatechinic acid... 

Brenz-. pyro-. -apfelsaure, /. maleic acid, -cain, n. Pharm.) pyrocain. -catechin, n. pyrocatechol, pyrocatechin. 

Brenz-holzsaure, /. pyroligneous acid, -kate-chtn, n. pyrocatechol, pyrocatechin. -kate-chingerbstoff, m. pyrocatechol tannin. 

The inhibitive efficiency of boric acid polyesters differs greatly. The highest efficiency is exhibited by polyesters of boric acid, aromatic diols and triols. This derives from the fact that in this case the radicals are accepted not only by boron, but also by the aromatic nucleus. Among the aromatic polyesters, most efficient is ester of boric acid and pyrocatechin due to the Frank-Rabinovich cage effect. The efficiency of inhibi-... 

Start with about 8.0ml of triethanolamine (TEA) at room temperature and a spoonful of water. Now add 2.5 grams of metol and stir to make a slurry. This is eventually going to make a liter but you can start in a 1/4-liter cup. After the slurry gets a little more fluid, add 15.0 to 20.0ml of some warm propylene glycol. Now you can transfer the metol slurry to the 750.0ml of warm propylene glycol and stir until dissolved. Now add 50.0 grams of pyrocatechin and stir until dissolved. Add 4.0 grams of ascorbic acid and stir until dissolved. Stock B is mixed the same as for Pyrocat-HD. 

Most of the chemicals used in black and white processes are safe and biodegradable. A few, such as selenium, pyrogallol, pyrocatechin, sodium hydroxide, and hydrochloric acid, require careful handling and disposal. Throughout The Darkroom Cookbook specific warnings and instructions will be given where appropriate. 

Unless a formula specifically calls for distilled water, in most cases tap water can be used. Even when distilled water is indicated, good quality, filtered tap water will usually suffice. A notable exception is those formulas which call for the use of pyrocatechin (catechol) or pyrogallic acid (pyro or pyrogallol). 

Propylene glycol, 75.0 ml Ascorbic acid, 0.5 g Pyrocatechin, 10.0 g Propylene glycol to make 100.0ml... 

In particular, the synthesis of a-naphthyl ether of pyrocatechinphosphorous acid is conducted in two stages. At the first stage pyrocatechinphos-phoromonochloride is synthesised from pyrocatechin and phosphorus trichloride ... 

The mixture in crystalliser 11 is cooled down to 70 °C and is gradually supplied with carbon tetrachloride the temperature is reduced to 50 °C. At further gradual cooling and agitation a-naphthyl ether of pyrocatechin-phosphorous acid crystallises. After that the mixture is completely cooled to 20 °C. The formed sediment is filtered in nutsch filter 14 and (to eliminate carbon tetrachloride completely) dried for some time in vacuum draft... 

Alizarin may be prepared artificially by fusing dibromanthra-quinone, nitroanthraquinone, or anthraquinonesulphonic acid with potash or soda [3] also by condensation of phthalic acid with pyrocatechin [4], and by reduction of rufigallic acid [13]. Alizarin has only been prepared on an industrial scale from anthra-quinone, and the artificial product has practically displaced madder in the course of the last twenty years. 

Synonyms 1,2-benzenediol catechol o-dihy-droxybenzene 2-hydroxyphenol o-diphe-nol o-hydroquinone o-phenylenediol oxyphenic acid pyrocatechin... 

The stability constants of uranyl amino- and mercapto-acid complexes have been determined. Among the acids investigated were cysteine, methionine, P-alanine, anthranilic acid, serine, threonine, and JV-ac tylglycine. Stability constants of a series of chloro-, bromo-, iodo-, and nitro-substituted salicylic acid and of o-pyrocatechinic, y-resorcylic, and gentisic acids complexes of UOj" have been measured 1 1 and 1 2 species were identified. It was observed that there was a distinct dependence of stability constant on the charge of the central metal atom in UO ", NpO, and Pu " tropolonato complexes. ... 

Figure 22 illustrates the data obtained for tyrosinase in the presence of oxygen and various mediators in the solution. It is seen that the highest stationary potential (—0.9 V) was achieved in the case of caffeic acid. The highest stability is observed in the system with a pyrocatechin-o-quinone, which preserved its activity for 50 hours. 

Phytochemistry The roots contains tannins (catechins, gallic acid, pyrogallol, and pyrocatechin), carbohydrates, and glycosides (Khalmatov 1964). The aboveground parts contain vitamins C, A, E, B, B, B, B,j, organic acids (malic and oxalic), sugars, fibers, hemiceUulose, pectin, and macroelements (Nuraliev 1989). Roots collected in Uzbekistan contained new phenylbutanoid and stilbene derivatives as well as the known compounds rhododendrol, epi-rhododendrin, lindleyin, torachrysone, etc. (Shikishima et al. 2001). 

I, 2-Benzenediol Catechin 1,2-Dihydroxybenzene ortho-Dihydroxybcnzene Oxyphenic Acid Pyrocatechin Pytocatechinic Acid Pyrocathechol Pyrocathechuic Acid Chemical Formula l,2-H0CsH40H (ii) Observable Characteristics — Physical State (as normally shipped) Solid Color White Odor None (iii) Physical and Chemical Properties — Physical State at 15 X and I atm. Solid Molecular Weight 110.11 Boiling Point at I atm. 413.9, 245.5, 418.7 Freezing Point 219.7, 104.3, 377.5 Critical Temperature Not pertinent Critical Pressure Not pertinent Specific Gravity 1.344 at 20°C (solid) Vapor (Gas) Density Not pertinent Ratio of Specific Heats of Vapor (Gas) Not pertinent Latent Heat of Vaporization Not pertinent Heat of Combustion -... 

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