Tris acid

Wien a little concentrated hydrochloric acid is added the green solution becomes yellow, because now the trichloride is formed and the influence of the second benzene ring is also suppressed, so that the (yellow) fuchsonimine type is formed. All triphenylmethane dyes dissolve in concentrated sulphuric acid with an orange-yellow colour exactly like triphenylcarbinol itself (carbonium salts, Kehrmann). By diluting the solution with water a colourless solution of the tri-acid benzenoid carbinol salt can be obtained. 

Figure 15 Examples of artificial collagen model peptide knots, (a) Regioselective artificial cystine knot, (b) dilysine scaffold,(c) c/s,c/s-1,3,5-trimethylcyclohexane-1,3,5-tricarboxylic acid Kemp tri acid , (d) TREN-(suc-OH)3, (Tris(2-aminoethyl)amine) succinic acid, (e) Fe + [2,2 -bipyridyl-peptide]3, " (f) monoalkyl chains, " (g) Boc-/3-Ala-TRIS-(OH)3 knot, and (h) N-terminal GFGEEG link. ...

The Krebs cycle is sometimes still referred to as the citric acid cycle, citric acid being one of the intermediates involved, and even the tricarboxylic acid cycie, in that several of the intermediates are tri-acids. As the name suggests, the process is a cycle, so that there is a reasonably constant pool of intermediates functioning in an organism, and material for degradation is processed via this pool of intermediates. Overall, though, the material processed does not increase the size of the pool. The compound... 

Glyceride. An ester of glycerol and fatty acids in which one or more of the hydroxyl groups of the glycerol have been replaced by acid radicals. Glycerides occur in nature and can be made synthetically. The most common ones are based oa fa try acids and occur in oild and fats. Mono and triglycerides are of commercial importance... 

Q = 0.2 M tris acid maleate (24.2 g of tris (hydroxymethyl) amino methane + 23.2 g of maleic... 

Although phosphoric acid has three hydroxy groups that can be used to form derivatives, the various reactions involved are again similar to those of carboxylic acids. For example, the reaction of phosphorus oxychloride, which can be viewed as a tri(acid chloride) of phosphoric acid, with excess dimethyl amine produces a triamide, hexa-methylphosphoric triamide ... 

Triazonane bearing three ethyl carboxylate 2,2 -bipyridine units was synthesized in 83% yield from the corresponding 6-bromo derivative 200 by a carboalkoxylation reaction promoted by a catalytic amount of Pd(0) (Equation 13). Subsequent smooth saponification resulted in the tris-acid 201 in 80% yield <2001JA2436, 2002JOC3933>. 

Resistance to streptomycin. Streptomycin [209] is produced by Strep-tomyces griseus. It is a tri-acidic base consisting of three components streptidine, streptose and N-methylglucosamine (Figure 7. II). The compound has a broad spectrum of antimicrobial activity, including Ps. aeruginosa (Table 7.13). 

The most important esters of this class are, the neutral or tri-acid esters of glycerol with the higher acids of the saturated and the unsdtu-rated series. The most important acids, in this connection, are given in the following list ... 

Constitution of Fats and Oils.—These acids which have all been previously discussed (pp. 136 and 170) embrace the more common ones that are found as esters in most oils and fats. The tri-acid ester of glycerol and palmitic acid may be taken as an example of a typical fat. It is exactly analogous to the ester of glycerol and acetic acid which we have just considered, and its formula is ... 

Complexes incorporating a constrained bis-carboxylate ligand, ZrX2(XDK) (X = Bn, NMe2 XDK = m-xylylenediamine bis(Kemp s triacid imide)) and Zr(XDK)2 have been synthesized and characterized structurally. This ligand was derived from Kemp s tri-acid imide derivative of m-xylylenediamine (92) and shown to chelate through the two carboxylic acid fragments.483... 

Prepare a solution of tris acid maleate 50 mM by mixing 6 g of tris(hydroxymethyl)aminomethane and 5.8 g of maleic acid in 1 L H O. Prepare a 50 ruM NaOH solution. Mix the 50 mL of the tris acid maleate solution and 48 mL of NaOH solution. Verify and adjust the pH by adding one of the Tris acid maleate or NaOH solutions. 

Marine Surface Sediments.. (0-2m) sediments beneath the highly productive upwelling regions in the Gulf of California and off the coast of Peru were chromatograph cally separated (see "Experimental") into (a) pheophytins, (b) pheophorbides (viz. mono carboxylic acids) and (c) chlorin acids (I.e. di-/tri-acids). Table II contains the result of these preliminary analyses and includes the concentration of pigments, present depositional environment and sample depth. 

Citric acid, a tri-acid, is very widespread in nature (e.g. lemons). Its very important biochemical and metabolic role (Krebs cycle) requires no further demonstration. Citric acid slows yeast growth but does not block it (Kalathenos et al.,... 

The first synthetic amide-based anion receptor 1 was reported in 1986 by Pascal Jr. and coworkers.This neutral cyclophane-type receptor was synthesized by reaction of l,3,5- m-(bromomethyl)benzene with three equivalents of cystearnine to form a triamine which was then clipped with one equivalent of the tris-acid chloride of 1,3,5-benzenetriacetic acid. The receptor contains three amide NH groups chat may be directed into the center of... 

As stated in Section 2.4, the condensation reaction may be the basis for the mechanism of stepwise polymerization. As long as the functionality equals 2 (di-acid and di-alcohol in polyester or di-amine in polyamide), only linear chains are obtained. However, once polyfunctionality prevails (appearance of tri-alcohol like glycerol, or tri-acid), reactive branches are formed that may interact and lead to a three-dimensional structure, called cross-linked (gelation). This is the basis for thermosetting polymers on one hand, or for stabilizing the elastomeric chain on the other hand (replacing vulcanization). 

The three polyester prepolymers prepared having varying viscosity (different di/tri acid ratio) with essentially the same hydroxyl content were used to define optimum reaction conditions for introduction of unsaturated groups via addition of glycidyl methacrylate to the liable hydroxyls. 

Di- and tri-acid triglycerides with one or two unsaturated chains have more complex phase behaviour. Cocoa butter which is dominated by triglycerides with oleic acid in the 2-position and palmitic and stearic acid in the 1- and 3-positions, exhibits six crystal forms. Transitions into the most stable form causes so-called blooming of chocolate. An interesting study of the polymorphism and the... 

It is surprising that relatively little work has been published on the use of unmodified castor oils in the synthesis of polyesters compared with studies involving several of its preliminary chemical modifications, as discussed below. A noteworthy excursion into incorporation of castor oil in biodegradable polyesters destined to function as drug carriers [11,12] describes the melt co-polycondensation of the oil with mannitol, as well as different aliphatic di-and tri-acids. Use of comonomers sebacic acid and citric acid is shown in Scheme 3.6. 

Comparable yields of glydne were obtained by Cheronis and Spitz-mueller (149) in the reaction at 60 to 65 C. of chloroacetic acid and a saturated solution of ammonium carbonate in aqueous ammonia. It was proposed (149, 204) that the proportion of di and tri acids was depressed in this mixture (containing relatively few moles of ammonia per mole of chloroacetic acid) because of the increase in carbamino ycinate ion resulting from an effect of the carbonate ion. It has beoa found that glycine may be synthesized satisfactorily with mixtures in which the equivalent ratio of ammonia to carbonate to chloroacetio acid is 5 to 4 to 1. 

The reaction is quite general as can be seen from the various reactions. Isopropylnaphthalene has been reported to add across the MA double bond. Methyl-p-toluate similarly adds, producing a unique tri-acid derivative... 

BSAA, now being called a chromate-free anodising process [35], theoretically uses no chromate salts in the cleaning stages or as the electrolyte. A minor exception to this chromate-free concept does, however, occur as some operators use a tri-acid based deoxidiser which does contain some chromic acid together with sulphuric and hydrofluoric acids. 

Active agent Free amines Di- or tri-acids NaCl and Na2S04... 

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