Dimethyl sulfoxide organic structure

Some results of the modification of lignin sulfonate Ultra B002 by reaction with terephthaloyl chloride are summarized in Table VI. The total hydroxyl content of the lignosulfonates as well as their derivatives are presented in Table VII. The hydrolytic resistance of selected products is evaluated in Table VIII. The results presented in Tables VI-VIII stress several advantages of the derivatives with terephthaloyl chloride. The modified lignin sulfonates were insoluble, or only very slightly soluble, in organic solvents. They were, however, soluble in dimethyl sulfoxide. Ordered structures were identified by X-ray studies (16,17). 

Bhattacharjya S and Balaram P. Effects of Organic Solvents on Protein Structures Observations of a Structured Helical Core in Hen Egg-white Lysozyme in Dimethyl Sulfoxide. Proteins Structure, Function and Genetics 1997 29 492-507. 

Phenol, the simplest and industrially more important phenolic compound, is a multifunctional monomer when considered as a substrate for oxidative polymerizations, and hence conventional polymerization catalysts afford insoluble macromolecular products with non-controlled structure. Phenol was subjected to oxidative polymerization using HRP or soybean peroxidase (SBP) as catalyst in an aqueous-dioxane mixture, yielding a polymer consisting of phenylene and oxyphenylene units (Scheme 19). The polymer showed low solubility it was partly soluble in DMF and dimethyl sulfoxide (DMSO) and insoluble in other common organic solvents. 

FIGURE 1.1 Structures of organic compounds referred to in the text (a) sucrose (also known as saccharose), (b) dimethyl sulfoxide (DMSO), (c) dimethylformamide (DMF), (d) sorbitol, (e) mannitol, (f) nitrilotriacetic acid (NTA), (g) citric acid, (h) N,N,N, N -fran,s-1,2-diaminocyclohexane-tetraacetic acid (CyTA), (i) saccharic acid, (j) glutamic acid. 

In recent years, a great diversity of structurally well-defined functionalized fullerenes has been designed and synthesized for that purpose. Some of them exhibit pronounced solubility in water (vide infra). But even for compounds being virtually insoluble in water, stable aqueous phases can be obtained in plenty of cases by diluting stock solutions of the compounds in polar organic solvents with various amounts of water. Notably, dimethyl sulfoxide (DMSO) and tetrahydro-furan (THF) have turned out to be excellent surfactants for preparing stable aqueous fullerene solutions (Angelini et al., 2005 Cassell et al., 1999 Da Ros et al., 1996 Gun kin et al., 2006 Illescas et al., 2003). Also cosolvents such as dimethylforma-mide (DMF) and methanol can be used to promote water solubility. After subsequent dilution of a saturated solution of C60 in benzene with THF, acetone and finally water, actually stable aqueous suspensions of pristine fullerene can be obtained (Scrivens et al., 1994). 

Alfassi, Z. B S. Padmaja, P. Neta, and R. E. Huie, Rate Constants for Reactions of NO, Radicals with Organic Compounds in Water and Acetonitrile, J. Phys. Chem., 97, 3780-3782 (1993). Allen, H. C., J. M. Laux, R. Vogt, B. J. Finlayson-Pitts, and J. C. Hemminger, Water-Induced Reorganization of Ultrathin Nitrate Films on NaCI—Implications for the Tropospheric Chemistry of Sea Salt Particles, J. Phys. Chem., 100, 6371-6375 (1996). Allen, H. C., D. E. Gragson, and G. L. Richmond, Molecular Structure and Adsorption of Dimethyl Sulfoxide at the Surface of Aqueous Solutions, J. Phys. Chem. B, 103, 660-666 (1999). Anthony, S. E R. T. Tisdale, R. S. Disselkamp, and M. A. Tolbert, FTIR Studies of Low Temperature Sulfuric Acid Aerosols, Geophys. Res. Lett., 22, 1105-1108 (1995). 

It is commonly agreed that enzymes are inactive in nearly anhydrous dimethyl sulfoxide (DMSO) [55] and that such inactivity might be a direct result of protein solubilization in the organic milieu, which causes deleterious changes in the proteins secondary and tertiary structures [56]. However, different authors have recently reported that some proteases, namely thermolysin (from Bacillus thermo-proteolyticus) and Proleather (from Bacillus subtilis), were still active in pure DMSO, despite the fact that proteins were indeed solubilized. The former enzyme cata-... 

It is still not clear why the furanose content is generally higher in organic solvents than in water. The effect on solvation of the water structure [p. 24] has been proposed as an explanation it seems to explain the interesting fact3 that addition of even a small proportion (< 10%) of dimethyl sulfoxide to an... 

A further dependence of the intrinsic viscosity on the content of water-dimethyl sulfoxide mixed solvent for the PVP-MAA/St copolymer system76 has been found the viscosity increases already beyond 30 vol-% of DMSO in the mixture. This indicates the dissociation of the polymer complex. At the same time, in the PMAA-PVP system27, the compact structure of the complex remains intact up to 70 vol-% content of DMSO, i.e. these complexes are very stable to the organic solvent. 

Abbreviations DMSO, dimethyl sulfoxide THF, tetrahydrofuran CHA, cyclohexylamine. Most acidities were measured at 25°C. Some are extrapolated values some are values from kinetic studies. Errors in some cases are several pK units. The farther the pK value is from 0-14, the larger the errors because of estimates and assmptions made when water is not the solvent. Values of pK s for the same substance in different solvents differ because of differences in solvation. Although the acids actual structures are listed in this Appendix, not all references do this. Thus, you may find lists of the pK values for organic amines that refer to the pK of the protonated amine rather than the amine itself. A good rule of thumb is that if the pK value given for an amine is less than 15, it must be the pK of the protonated amine rather than the amine itself. 

Phenol, the simplest and most important phenolic compound in industrial fields, is a multifunctional monomer for oxidative polymerization, and hence, conventional polymerization catalysts afford an insoluble product with uncontrolled structure. On the other hand, the peroxidase catalysis induced the polymerization in aqueous organic solvent to give a powdery polymer consisting of phenylene and ox-yphenylene units showing relatively high thermal stability (Scheme 2).5,6 In the HRP and soybean peroxidase (SBP)-catalyzed polymerization in the aqueous 1,4-dioxane, the resulting polymer showed low solubility the polymer was partly soluble in N,N-dimethylformamide (DMF) and dimethyl sulfoxide and insoluble in other common organic solvents.5 On the other hand, the aqueous methanol solvent af-... 

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