Tricarboxylic acid

DL-l-Hydroxypropane-l,2,3-tricarboxylic acid (isocitric acid) (Other values on Vol,3, p.l60) 

Na salt used as background electrolyte (CH ) N salt used as background electrolyte 

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VII,10. AMMONIUM SALT OF AURIN TRICARBOXYLIC ACID ( ALUMINON )... 

Extension of the Hantzsch s Synthesis to Thiazole Carboxylic and Thiazole Acetic Acids (Table II-IO). Mono-, di-, and tricarboxylic acids are among the most easily prepared thiazole derivatives. 

Glutamic acid is formed m most organisms from ammonia and a ketoglutaric acid a Ketoglutaric acid is one of the intermediates m the tricarboxylic acid cycle (also called the Krebs cycle) and arises via metabolic breakdown of food sources carbohy drates fats and proteins... 

Alnminon (qualitative test for aluminum). The reagent consists of 0.1% solution of the ammonium salt of aurin tricarboxylic acid. A bright red precipitate, persisting in alkaline solution, indicates aluminum. 

Condensation polymers prepared with some monomer of functionality greater than 2, for example, a polyester formed with some glycerol or tricarboxylic acid. 

As an example of the quantitative testing of Eq. (5.47), consider the polymerization of diethylene glycol (BB) with adipic acid (AA) in the presence of 1,2,3-propane tricarboxylic acid (A3). The critical value of the branching coefficient is 0.50 for this system by Eq. (5.46). For an experiment in which r = 0.800 and p = 0.375, p = 0.953 by Eq. (5.47). The critical extent of reaction, determined by titration, in the polymerizing mixture at the point where bubbles fail to rise through it was found experimentally to be 0.9907. Calculating back from Eq. (5.45), the experimental value of p, is consistent with the value =0.578. 

In addition to its presence in fmits, S(—)-malic acid has been found in cultures of a variety of microorganisms including the aspergiUi, yeasts, species of Sekrotinia, and Penicillium brevicompactum. Yields of levorotatory malic acid as high as 74% of theoretical have been reported. Iron, manganese, chromium, or aluminum ions reportedly enhance malic acid production. S(—)-Mahc acid is involved in two respiratory metaboHc cycles the Krebs tricarboxylic acid... 

H-Azepine-2-thione, hexahydro-1 -methyl- C NMR, 7, 498 <79AJC567> 4H-Azepine-2,6,7-tricarboxylic acid, trimethyl ester AG 7, 499 (72JA2770)... 

Isoxazole-5-thione, 4-arylazo-3-methyl-tautomerism, 6, 57 Isoxazole-5-thiones tautomerism, 6, 11 Isoxazole-3,4,5-tricarboxylic acid esters... 

Thiophene-2,3,4-tricarboxylic acids synthesis, 4, 884, 920 Thiophene-2,3,5-tricarboxylic acids synthesis, 4, 920... 

D. Methionine.—A suspension of 21.5 g. (0.063 mole) of this tricarboxylic acid in 350 cc. of hot water is heated on the steam bath and 40 cc. of concentrated hydrochloric acid (sp. gr. 1.19) is added. Carbon dioxide is immediately evolved and the substance goes into solution. After heating for one and a half hours, 200 cc. more of concentrated hydrochloric acid is added and heating is continued for forty-five minutes longer. The solution, on cooling, deposits phthalic acid this is filtered off and washed with two 50-cc. portions of water (Note 3). The combined filtrate and washings are evaporated to dryness on the steam bath under reduced pressure, and the dry residue is dissolved in... 

Methylsuccinic acid has been prepared by the pyrolysis of tartaric acid from 1,2-dibromopropane or allyl halides by the action of potassium cyanide followed by hydrolysis by reduction of itaconic, citraconic, and mesaconic acids by hydrolysis of ketovalerolactonecarboxylic acid by decarboxylation of 1,1,2-propane tricarboxylic acid by oxidation of /3-methylcyclo-hexanone by fusion of gamboge with alkali by hydrog. nation and condensation of sodium lactate over nickel oxide from acetoacetic ester by successive alkylation with a methyl halide and a monohaloacetic ester by hydrolysis of oi-methyl-o -oxalosuccinic ester or a-methyl-a -acetosuccinic ester by action of hot, concentrated potassium hydroxide upon methyl-succinaldehyde dioxime from the ammonium salt of a-methyl-butyric acid by oxidation with. hydrogen peroxide from /9-methyllevulinic acid by oxidation with dilute nitric acid or hypobromite from /J-methyladipic acid and from the decomposition products of glyceric acid and pyruvic acid. The method described above is a modification of that of Higginbotham and Lapworth. ... 

Aurin tricarboxylic acid [4431-00-9] M 422.4, m 300". The acid is dissolved in aqueous NaOH, NaHS03 solution is added until the colour is discharged and then the tricarboxylic acid is ppted with HCI [Org Synth Coll Vol I 54 1947]. Do not extract the acid with hot water because it softens forming a viscous mass. Make a solution by dissolving in aqueous NH3. See Aluminon for the ammonium salt. 

Chemical Designations - Synonyms 2-Hydroxy-l,2,3-Propane-Tricarboxylic Acid beta-Hyd-roxytricarballylic Acid beta-Hydroxytricarboxylic Acid Chemical Formula H0C(CH2C0jH)jC02H. Observable Characteristics - Physical State (as normally shipped) Solid Color White Odor None. Physical and Chemical Properties - Physical State at 15 T7 and 1 atm. Solid Molecular Weight 192.1 Boiling Point at 1 atm. Not pertinent (decomposes) Freezing Point 307, 153, 426 Critical Temperature Not pertinent Critical Pressure Not pertinent Specific Gravity 1.54 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 -4,000, -2,220, -93 Heat of Decomposition Not pertinent. 

The position in which the veratryl residue is attached to this isoquinoline nueleus in papaveraldine and papaverine is determined by the formation of pyridine-2 3 4-tricarboxylic acid in the oxidation of papaverine by hot permanganate. On the basis of these results, Goldschmiedt assigned the following formula to papaveraldine —... 

Papaverinic acid, CieHjjO N. HjO, crystallises in small tablets, m.p. 233°. It is dibasic, readily forms an anhydride, furnishes an oxime and a phenylhydrazone, contains two methoxyl groups, and on oxidation yields veratric and pyridine-2 3 4-tricarboxylic acids, and hence is represented by the following formula —... 

If the NHj group is eliminated first, as in the fusion of eolehieine with potassium hydroxide, and the product is oxidised with permanganate, terephthalie and trimellitic (benzene 1 2 4-tricarboxylic) acids are formed, which should come from a third benzene ring. 

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