الفهرس 
1. INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
3. Pharmaceuticals:
DMA can be used both as a solvent and as a reagent in the production of various pharmaceuticals. In the production of novel x-ray contrast media, DMA is used as a solvent. Cephalosporins, which are among one of the leading classes of antibiotics, are partly produced from derivatives of 7-ADCA (7-aminodeacetoxy-cephalosporanic acid). DMA is used in the manufacturing process.
4. Various polymers:
DMA is a good solvent for polyimide resins, both in coating and film production. It is also the ideal solvent for the production of dialyser membranes, based on polysulfones. A mixture of DMA and lithium chloride is a useful solvent for cellulose fibers in several applications.
5. Dimethylacetamide is also used as an excipient in drugs, e.g. in Vulmon (teniposide), Busulfex (busulfan) or Amsidine (amsacrine).
6. Dimethylacetamide is a medium potency reproductive toxicant (toxic for reproduction).
Importance of Dimethylacetamide 24-26
1. Dimethylacetamide is commonly used as solvent for fibers (e.g., polyacrylonitrile, spandex) or in the adhesive industry. It is also employed in the production of pharmaceuticals and plasticizers as reaction medium.
2. It is used in the production of polyacrylonitrile and polyurethane based fibers, films and coatings. The polar nature of DMA enables it to act as a combined solvent and reaction catalyst in many reactions producing high yields and pure product in short time period
3. There are indications that dimethylacetamide is incompatible with polycarbonate. Devices (e.g. syringes) that contain polycarbonate dissolve when coming into contact with dimethylacetamide.
4. The use of amide + water mixtures as solvents has attracted much attention in recent years, as solvents in the study of various physico-chemical properties of electrolytic solution. Mixing DMA with water caused contraction in volume of several systems due to the interaction involving hydrogen bond formation between water and DMA.
1.3.4. The structure of Dimethylsulfoxide 27-41:
N,N-Dimethylsulfoxide (DMSO) is an organo sulfur compound with the formula (CH3)2SO. This colorless liquid is an important polar aprotic solvent that dissolves both polar and non-polar compounds and is miscible in a wide range of organic solvents as well as water. It has a relatively high melting point. DMSO has the unusual property that many individuals perceive a garlic-like taste in the mouth after contact with the skin.27
In terms of chemical structure, the molecule has idealized Cs symmetry. It has a trigonal pyramidal molecular geometry consistent with other three-coordinate S (IV) compounds, with a non-bonded electron pair on the approximately tetrahedral sulfur atom.28
Since DMSO is an important solvent studies concerning solute-solvent interaction. DMSO is highly associated solvent and it is found that cations arث mostly solvated in it whilst anions remain relatively encumbered by DMSO. 29
Dimethylsulfoxide preparation 30
Dimethylsulfoxide is produced from dimethylsulfide, a by-product of kraft pulping. It is industrially produced by oxidation of dimethylsulfide with oxygen or nitrogen dioxide.
The sulfur center in DMSO is nucleophilic toward soft electrophiles and the oxygen is nucleophilic toward hard electrophiles. With methyl iodide it forms trimethylsulfoxonium iodide, [(CH3)3SO]I:
(CH3)2SO + CH3I → [(CH3)3SO]I
This salt can be deprotonated with sodium hydride to form the sulfurylide:
[(CH3)3SO]I + NaH → [(CH3)2CH2SO + NaI + H2
Importance of Dimethylsulfoxide 31
1. The methyl groups of DMSO are only weakly acidic, with a pKa=35. For this reason, the basicities of many weakly basic organic compounds have been examined in this solvent.
2. Deprotonation of DMSO requires strong bases like lithium diisopropylamide and sodium hydride. Stabilization of the resultant carbanion is provided by the S(O)R group. The sodium derivative of DMSO formed in this way is referred to as ”dimsylsodium”. It is a base, e.g., for the deprotonation of ketones to form sodium enolates, phosphonium salts to form Wittig reagents, and formamidinium salts to form diaminocarbenes. It is also a potent nucleophile.
3. In organic synthesis, DMSO is used as a mild oxidant.
Properties of Dimethylsulfoxide 32, 33
1. DMSO is a polar aprotic solvent and is less toxic than other members of this class, such as dimethylformamide, dimethylacetamide, N-methyl-2-pyrrolidone, and is frequently
used as a solvent for chemical reactions involving salts, most notably Finkelstein reactions and other nucleophilic substitutions.
2. It is also extensively used as an extractant in biochemistry and cell biology. Because DMSO is only weakly acidic, it tolerates relatively strong bases and as such has been extensively used in the study of carbanions.
3. Because of its high boiling point, 189 °C (372 °F), DMSO evaporates slowly ate.