HYDROXYETHYL Subject

In a test at Mayak nuclear fuel reprocessing plant in Russia, alkaline high-active waste was subjected to extraction by a mixture of parent /-butyl calix[6]arene, 2- [bis(2-hydroxyethyl)amino]methyl -4-alkylphenol, and a solubilizer in dodecane. 

A mean minimum steady-state serum concentration of 0.004 pg/ml of clopenthixol was reported in 24 subjects, who had been receiving average doses of 200 mg intramuscularly every 4 weeks, for 5 to 6 months (S. J. Denckerer a/., Actapsychiat. scand., 1980,61, Suppl. 279, 55-63). Following an oral dose of 30 mg of clopenthixol to 1 subject, a peak serum concentration of about 0.005 pg/ml of d -clopenthixol was attained in about 3 hours the peak concentration of the inactive /ra/i5-isomer was slightly higher and was attained after 4 hours the serum concentrations declined slowly and were still measureable after 48 hours only traces of the des-(2-hydroxyethyl) metabolite were detected (T. Aaes-Jorgensen, J. Chromat., 1980,183 Biomed. AppL, 9, 239-245). 

Hydroxyethyl cellulose is subject to enzymatic degradation, with consequent loss in viscosity of its solutions. Enzymes that catalyze this degradation are produced by many bacteria and fungi present in the environment. For prolonged storage, an antimicrobial preservative should therefore be added to aqueous solutions. Aqueous solutions of hydroxyethyl cellulose may also be sterilized by autoclaving. 

The photoinduced substitution of 1-isoquinolinecarbonitrile (238) by ethanol to give l-(l-hydroxyethyl)isoquinoline (239) has been found to be subject to a magnetic field effect. This suggests that the reaction proceeds predominantly via... 

The halogenated biphenyls represent a class of compounds where reductive conditions [51] (solvated electron, aromatic radical anions, ketyl radicals) answer the purpose much better than the OH radical. However, this is to be seen in the context that the toxicity of the halogenated biphenyls exceeds that of biphenyl itself by such a wide margin that the latter compound is considered as relatively harmless. Complete removal of the pollutant would still have to rely on the oxidative pathway. A similar situation exists with respect to nitro-aromatics [52] which are also subject to reductive attack, indirectly by the OH radical via a-hydroxyethyl radical generated from the additive ethanol [53]. 

The subject of surfactant-modified, water-soluble polymers, briefly discussed in Water-Soluble Polymers, is addressed in the last three sections (Chapters 16-28) of this book. These associative thickeners are covered in detail, ranging from the maleic acid copolymers of variable compositions introduced in various commercial markets in the early 1960s to the most recent entries (that is, in the open literature), hydrophobe-modified poly (acrylamide). Chapter 23 is complementary to the spectroscopic studies in Chapters 13-15 it explores new approaches to understanding associations in aqueous media. The three hydrophobe-modified polymers that have gained commercial acceptance in the 1980s, (hydroxyethyl)cellulose, eth-oxylate urethanes, and alkali-swellable emulsions, are discussed in detail. In particular, hydrophobe-modified (hydroxyethyl)cellulose, which is... 

Alcoholism. Many investigations showed that alcoholism modulates the level of PTM-like phosphorylation [47], Alcohol consumption was shown to decrease the sialic acid conjugation to transferrin, an important carrier protein secreted from the liver to blood and other glycoproteins. This observation led to the development of a laboratory test for chronic alcohol use. Similar studies showed that direct production of alcohol metabolism (alpha-hydroxyethyl radicals, acetaldehyde and lipid peroxides) causes PTM that correlates with alcohol consumption in animal models and human subjects [48]. 

The transesterification of N-(j3-hydroxyethyl)ethylenediamine by p-nitro-phenyl picolinate has been shown to be subject to zinc ion catalysis by Sigman and Jorgensen 27). Their investigations indicate that reaction very probably occurs through the formation of a ternary complex in which zinc ion functions both to lower the pKa of the hydroxyethyl moiety, and to serve as a template for the reaction. The high specificity manifest in this catalytic process is emphasized by the fact that no catalysis of acyl-group transfer occurs when N-((8-hydroxy-ethyl) ethylenediamine is replaced by ethylenediamine, 1,5-diaminopentane, di-ethylenetriamineor aminoethanol. Furthermore, the reactions of the p-nitrophenyl esters of isonicotinic and acetic acids with N-((8-hydroxyethyl) ethylenediamine are not subject to zinc ion catalysis. 

The pKa of the Zn(II)-complexed /5-hydroxyethyl moiety, as estimated from the pH-dependence of the observed rate of transesteiification (assuming that the reaction is subject to a specific base-catalyzed reaction), is approximately 8.4. This corresponds to an estimated pKa perturbation of 3—4 units relative to the pKa of the free hydroxyethyl group. Although the authors make no mention of this point, the observed 33-fold increase in the rate of hydrolysis of p-nitrophenyl-picohnate by zinc ion raises the possibility that hydrolysis under these conditions occurs via an analogous mechanism involving the nucleophilic activation of coordinated (inner sphere) water. 

The latices studied were composed primarily of either polystyrene or a copolymer of -butyl acrylate and methyl methacrylate. Their diameters were of order 0-4yjan. Hydroxyethyl cellulose was the water soluble polymer subjected to detailed investigations, but poly(oxyethylene) and polyacrylamide exhibited a qualitatively similar pattern of flocculation behaviour. Six different samples of hydroxyethyl cellulose were studied, their molecular weights varying from 68 500 to 887 000. 

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