Multifunctional Naturally occurring

Maleic anhydride CAS. 108-3I-6. til, maleic acid [CAS 110-16-7]. (2), and I umarie acid [CAS 110-17-81. i3) are multifunctional chemical intermediates that lind applications in nearly every Held id industrial chemistry. Each molecule contains two acid carbonyl groups and a double bond in the u. position. Maleic anhydride and maleic acid are important raw materials used in the manufacture of phthalic-type alkyd and polyester resins, surface coatings, lubricant additives, plasticizers. copolymers, and agricultural chemicals [see Alkyd Resins Polymers, and Lubricant). Both chemicals derive their common names from naturally occurring malic acid. 

Lactic acid (2-hydroxypropionic acid) is a naturally occurring multifunctional organic acid that is found in many food products, particularly in those which involve natural or processed fermented food preparations. Currently, more than 70% of lactic acid is used as acidulents, food preservatives, and feedstock for the manufacture of calcium stearoyl-2-lactylates in the baking industry. The consumption of lactic acid is estimated to be around 30 million lb in the US with an estimated increase of 6% per year. Therefore, lactic acid is an intermediate-volume specialty chemical used chiefly for food processing. 

Other amphoteric surfactants include the betaines derived from imidazolines, which absorb UV light and the lecithins or phosphati-dicholines, which are naturally occurring phospholipids [7]. Multifunctional surfactants associating a nonionic moiety with a charged one are considered ionic surfactants. 

This goal was the objective of the present investigation, which is concerned with the preparation of polymers from naturally-occurring, multifunctional hydroxyacids and aminoacids. On degradation such polymers could revert in the body to their original natural products. The natural products chosen for this purpose were malic acid (I), which is an intermediate in the citric acid cycle, and aspartic acid (II), which is a common component of many proteins. High yield synthetic procedures were developed for the conversion of both compounds into cyclic monomers, which could be polymerized to polymers of controlled molecular weights. Malic acid was converted to the 3-lactone and aspartic acid to the 3-lactam, and each was polymerized to its respective polyester and polyamide, as outlined in the equations below ... 

The multifunctional nature of Cinchona alkaloids makes them especially prone for a complex reactivity that occurs with a degradation or rearrangement of the carbon moiety, often controlled by the stereochemistry of the particular alkaloid. These characteristic for Cinchona alkaloid transformations include an acid-catalyzed formation of cinchotoxines 59 described as early as in 1853 by Pasteur [108] or synthesis of diverse cyclic ethers, for example, )S-isoquinidine 60 or jS-isocupreidine 61, bearing oxazatwistane moiety [180, 201, 202] (Scheme 21.5). This can be used as an efficient catalyst of a stereoselective Baylis-HiUman reaction [8-10, 203, 204]. Hoffmann studied in detail the two distinct cage rearrangements... 

The self-assembly of natural and synthetic multifunctional unimers occurs, in fact, by a combination of classical molecular recognition and growth mechanisms. Self-assembled, reversible structures include linear, helical, columnar, and tubular polymers micelles monolayers and three-dimensional phases and networks. Self-assembled systems based on an interplay between covalent chains and supramolecular interactions are also important. Typical examples are side-chain SPs (Chapter 5), host-guest polymeric composites and dendrimers (Chapters 2 and 7), polymers with mechanical bonds (Chapter 8), and block copolymers (Chapters 9-11). 

Schematically shown are two separate P-oxidation systems, one involved in degradation of straight chain fatty add derivatives (left side), the other handling 2-methyl-branched compounds (right side), each of them consisting of four steps that are catalyzed by an acyl-CoA oxidase, a multifunctional protein (MFP) (containing two or more activities) and a thiolase. Only the proteins belonging to the left system are (at least in rodents) induced by peroxisome proliferators and correspond to those initially discovered and characterized in rat liver. In rat, the CoA-esters of bile add intermediates and pristanic acid are desaturated by separate enzymes (highlighted in italic), while in man only one oxidase appears to be involved. Before the naturally occurring 2R-pristanic acid and 25R-bile acid intermediates can be desaturated, a racemisation reaction is required. The 2-methyl-2-enoyl-CoAs, generated by the oxidases, are thought to be hydrated by the same MFP-2. Under normal conditions, the intermediates are believed to be channeled from...

There is a continuing need for the development of multifunctional materials. The ability to develop a material that contains a user-defined blend of two or more functions into an exclusive composite is desirable in the assembly of novel, multifunctional self-cleaning surfaces. Naturally occurring superhydrophobic surfaces have inspired researchers to devise fabrication techniques for biomimetic synthetic surfaces that generate an... 

Falardeau, P., Champagne, P., Poyet, P., Hariton, C., and Dupont, E. (2001) Neovastat, a naturally occurring multifunctional antiangiogenic drug, in phase III clinical trials. Semin. Oncol, 28, 620-625. 

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