Pharmaceutical use

Pharmaceutically useful steroids may be either obtained by total synthesis or by degradation and functional group conversions from inexpensive natural steroids. Both approaches will be discussed in this section (H. Langecker, 1977 R.T. Blickenstaff, 1974). 

Some plant and animal steroids occur in large quantities and can be used as inexpensive starting materials for pharmaceutically useful steroid hormones (see table 22). 

Biosynthesis ofS(— )-M llc Acid. Aqueous fumaric acid is converted to levorotatory malic acid by the intracellular enzyme, fumarase, which is produced by various microorganisms. A Japanese process for continuous commercial production of S(—)-mahc acid from fumaric acid is based on the use of immobilized Brevibacteriumflavum cells in carrageenan (32). The yield of pyrogen-free S(—)-mahc acid that is suitable for pharmaceutical use is ca 70% of the theoretical. 

Alkenylsuccinic anhydrides made from several linear alpha olefins are used in paper sizing, detergents, and other uses. Sulfosuccinic acid esters serve as surface active agents. Alkyd resins (qv) are used as surface coatings. Chlorendric anhydride [115-27-5] is used as a flame resistant component (see Flame retardants). Tetrahydrophthalic acid [88-98-2] and hexahydrophthalic anhydride [85-42-7] have specialty resin appHcations. Gas barrier films made by grafting maleic anhydride to polypropylene [25085-53-4] film are used in food packaging (qv). Poly(maleic anhydride) [24937-72-2] is used as a scale preventer and corrosion inhibitor (see Corrosion and corrosion control). Maleic anhydride forms copolymers with ethylene glycol methyl vinyl ethers which are partially esterified for biomedical and pharmaceutical uses (189) (see Pharmaceuticals). 

A major pharmaceutical use of poly(oxyethylene) sorbitan fatty acid esters is in the solubilization of the oil-soluble vitamins A and D. In this way, multivitamin preparations can be made which combine both water- and oil-soluble vitamins in a palatable form. 

An excellent overview of vitamin analytics is available (13). Specifications for the vitamins are available for food use (14) and pharmaceutical use (15). 

Specifications for niacin and niacinamide for food use are given in the Vood Chemicals Codex (63) and for pharmaceutical use in the United States Pharmacopeia (64). The Codex also gives specifications for niacinamide ascorbate. 

Estimates of world demand iu 1979 were as high as 1300 x 10 lU of vitamin D. This was divided iuto thirds for Europe, the United States, and the rest of the world, respectively. Of this demand, 90% was estimated for animal-feed fortification and 10% for food and pharmaceutical uses. It is estimated that the demand will be 1500—1600 x 10 IU iu 1997 for animal usage and 100 x 10 IU for human use. The United States will require approximately 500 TU (1 trillion units = 25 kg i j -vitamin D or 17 t of resiu) for animal use and 30 TU (approximately 1 t of crystalline (7j -vitamin D ) for human use. This represents approximately 50 t of vitamin D resiu/yr for animal use worldwide and about 2.5 t of crystalline vitamin D for human use. A substantial proportion of the vitamin D is imported, and with all uses iucluded, it is estimated that 80—90% of the sales are of vitamin D. ... 

In pharmaceutical uses, the general inertness of lanolin and its derivatives, together with their ease of emulsification (185), have been important criteria. These properties are also important in cosmetics, but with emphasis also on the abiHty to absorb large quantities of water or, after suitable modification, to stabilize o/w emulsions. 

Until 1930, approximately 90% of bismuth usage was for pharmaceutical appHcations (9). From that point until the 1970s, research produced new appHcations that greatiy expanded the uses of the metal. At that point the pharmaceutical use accounted for about 50% of the total bismuth consumption. By 1991, the fusible alloy category along with the other subdivisions each accounted for about 10% of the bismuth usage. Pharmaceutical usage was down to 20%. 

The neutral glasses are generally less resistant than the hard borosilicate type, but are more easily melted and shaped. They are formulated so that the pH of aqueous solutions is unaffected by contact with the glass, making it particularly suitable in pharmaceutical use for the storage of pH-sensitive drugs. 

Aziridine-2-carboxylates are playing important roles in the synthesis of natural products and pharmaceutically useful molecules. In this section, applications of chiral nonracemic aziridine-2-carboxylates in the synthesis of natural products are discussed. 

Typical examples that fall in this group would be the determination of the active ingredients in analgesic tablets for pharmaceutical use, such as aspirin or codeine or the analysis of a food product such as margarine. Examples of both these analyses will be described to illustrate the sample preparation procedure. 

Pharmaceutical uses, of thiazolium salts, 80 of thiazolocyanines, 80 2-tautomeric equilibrium (imino) U.V. spectra, 263... 

For thousands of years, nature has provided humankind with a large variety of materials for the most diversified applications for its survival, such as food, energy, medicinal products, protection and defense tools, and others. The pharmaceutical industry has benefitted from such diversity of biomaterials and has exploited the use of natural products as sources of both drugs and excipients. One example of a promising biomaterial for pharmaceutical use is xylan, a hemicellulose largely found in nature, being considered the second most abundant polysaccharide after cellulose. 

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