P acetate

C10H10N4O2S. White powder, which darkens on exposure to light m.p. 255-256 C. Prepared by condensing p-acet-amidobenzenesulphonyl chloride with 2-aminopyrimidine and subsequent hydrolysis. Soluble sulphadiazine is the sodium salt. Sulphadiazine is the least toxic of the more potent sulphonamides. ... 

The important drug sulphapyridine (or M. B. 693 or 2-sulphaniIyl-aminopyridine) may be readily synthesised from 2-aminopyridine and p-acet-amidobenzenesulplionyl chloride (Section IX,9) as follows ... 

Sulphapyridine. Dissolve 18-8 g. of 2-aminopyridine in 40 ml. of dry pyridine (Section 11,47,22) in a 250 ml. flask and add 48 0 g. of p-acetamidobenzenesulphonyl chloride (4) the temperature rises to about 70°. Cool, add excess of water, filter the precipitated 2-(p-acet-amidobenzonesulphonamido)p3Tidine (s acetyl-sulphapyridine) at the pump and recrystallise it from 50 per cent, acetic acid. The yield of pm product, m.py. 224°, is 46-5 g. 

Figure 8 Dissolution-time profile of acetaminophen crystals (75 mg, 355-500 pm) in water at 4°C. The crystals were grown at 30°C and at 240 rpm from aqueous solutions containing initially 23.1 g/dm3 acetaminophen and the following concentrations of p-acet-oxyacetanilide a ( ) Zero ( ) 100 mg/dm3 (A) 300 mg/dm3 (O) 500 mg/dm3. (Reprinted with permission from Ref. 6.)...

Salt marsh, New Positive relation Soil extractable P (acetic Theodose... 

Baeyer-Villiger oxidation of ketone 104 with metachloroperbenzoic (MCPBA) acid afforded lactone 105 (86 %). There was no detectable trace of the product resulting from oxygen insertion between centers C(2) and C(3). On treatment with acidic methanol, 105 was transformed into a 90 4 mixture of a- and p-acetal-acids 106 (94 %). Treatment with 2 equivalents of MeLi afforded methyl ketone 107... 

Cyclolanost-24-methylene-3 -P-acetate P1CS033 Cymen-8-ol, para EO , Pl snz Cymene, para Pl snz, CS068 qCS156 Inflorescence ... 

S ATP -P acetate <1-18> (<8> acetate kinase/phosphotransacetylase, major role of this two-enzyme sequence is to provide acetyl coenzyme A which may participate in fatty acid synthesis, citrate formation and subsequent oxidation [1] <3> function in the metabolism of pyruvate or synthesis of acetyl-CoA coupling with phosphoacetyltransacetylase [15] <11> function in the initial activation of acetate for conversion to methane and CO2 [19] <10> key enzyme and responsible for dephosphorylation of acetyl phosphate with the concomitant production of acetate and ATP [30]) (Reversibility r <1-18> [1, 2, 5-21, 24-27, 29-33]) [1, 2, 5-21, 24-27, 29-33]... 

Winzer, K. Lorenz, K. Duerre, P. Acetate kinase from Clostridium acetobutylicum a highly specific enzyme that is actively transcribed during acidogenesis and solventogenesis. Microbiology, 143, 3279-3286 (1997)... 

The scheme proposed for the reaction over HFAU was that PA dissociates in phenol (P) and ketene and that o-HAP, which was highly favoured over the para isomer, results partly from an intramolecular rearrangement of PA, partly from acyl group transfer from PA to P whereas p-HAP results from this latter reaction only. In these experiments, the zeolite deactivation was very fast, as a result of coke deposition and zeolite dehydroxylation. Catalyst stability can be considerably improved by operating at lower temperatures and especially by substituting equimolar mixtures of PA and water or P and acetic acid for PA. Much higher HAP yields were obtained by using the P - acetic acid mixture as reactants.[68]... 

The scheme (Figure 3.5) of the transformation of this P - acetic acid mixture over HMFI at 553 K was established from the effect of conversion (or of contact time) on product distribution.[69] At short contact times (i.e. at low conversions), PA was practically the only reaction product. However, there was also formation of a very small amount of o-HAP (Figure 3.6). This means that O acetylation is much faster than C acetylation (ca. 20 times) and that the latter reaction leads to the ortho isomer only. Because of the high rate of O acetylation, thermodynamic equilibrium between P, acetic acid and PA was established at relatively short contact times. At high conversions, the formation of o-HAP involved the participation of PA as demonstrated by the decrease in PA yield and the apparent secondary mode of o-HAP formation (Figure 3.6). This mode of o-HAP formation from PA is mainly intermolecular involving the acetylation of P by PA. The intramolecular transformation of PA into o-HAP is much slower as shown by comparing the transformations of pure PA and of an equimolar mixture of PA and P.[69] The formation of small amounts of p-HAP would result mainly from the hydrolysis of... 

Optimal operating conditions and catalysts Only the effect of temperature was investigated. Generally, the higher the temperature, the higher the conversion of PA, but the faster the deactivation and the lower the selectivity for HAP (see, for example, in Table 3.8 with a HBEA sample[77]). The same can be observed for the transformation of a 1 1 molar P-acetic acid mixture over HMFI,[73,74] but the deactivation was much slower than for PA transformation.[74] A zero reaction order... 

The checkers employed E. I. du Pont de Nemours and Company, Inc., c.p. acetic acid, which was further purified by distillation from potassium permanganate. 

The isomeric o-aimnophenylmercurie acetate is difficult to separate from the larger amount of the p- compound which would separate with it if the filtrate from the initial crop of the p- acetate were allowed to stand. Dimroth found, however, that there was a considerable difference m the solubilities of the chlorides, so the filtrate is treated with an excess of sodium chloride solution, precipitating p-aminophenylmercuric chloride in the amorphous state, while the o-ammo chloride separates in crystalline form. The mixture is sucked off, dried, and the 0- derivative extracted with not too much warm alcohol, separating as leaflets after the solution is chilled and allowed to stand The amorphous residue of p- chloride may be boiled with alcohol or benzene, and separates from the cold solution as leaflets melting at 1880, with decomposition. 

Trimethylsilyl)ethyl 4,6-O-p- Acetal Toluene Amb. Benzoyl chloride 46 39 — 134... 

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