Synthetic polymers, imprinted

Preparation of Synthetic Polymers Imprinted with L- or D-Phenylalanine Anilide... 

Preparation of Synthetic Polymers Imprinted with (H-)-Ephedrine, (H-)-Pseudoephedrine, and (H-)-Norephedrine [48]... 

Suedee, R., Songkram, C., Petmoreekul, A., Sangkunakup, S., Sankasa, S. and Kongyarit, N., Thin-layer chromatography using synthetic polymers imprinted with quinine as chiral stationary phase, J. Planar Chromatogr., 11, 272-276, 1998. 

Aboul-Enein, H.Y., El-Awady, M.I. and Heard, C.M., Direct enantiomeric resolution of some cardiovascular agents using synthetic polymers imprinted with —)S-timolol as chiral stationary phase by thin layer chromatography, Pharmazie, 57, 169-171, 2002. 

Chiral synthetic polymer phases can be classified into three types. In one type, a polymer matrix is formed in the presence of an optically pure compound to moleculady imprint the polymer matrix (Fig. 10) (107,108). Subsequent to the polymerisation, the chiral template is removed, leaving the polymer matrix... 

Takeuchi, T., Fukuma, D., and Matsui, J., Combinatorial molecular imprinting an approach to synthetic polymer receptors, Anal. Chem., 71, 285, 1999. 

Steinke,., Sherrington, D. C. and Dunkin, I. R. Imprinting of Synthetic Polymers Using Molecular Templates. Vol. 123, pp. 81-126. 

Different classifications for the chiral CSPs have been described. They are based on the chemical structure of the chiral selectors and on the chiral recognition mechanism involved. In this chapter we will use a classification based mainly on the chemical structure of the selectors. The selectors are classified in three groups (i) CSPs with low-molecular-weight selectors, such as Pirkle type CSPs, ionic and ligand exchange CSPs, (ii) CSPs with macrocyclic selectors, such as CDs, crown-ethers and macrocyclic antibiotics, and (iii) CSPs with macromolecular selectors, such as polysaccharides, synthetic polymers, molecular imprinted polymers and proteins. These different types of CSPs, frequently used for the analysis of chiral pharmaceuticals, are discussed in more detail later. 

Synthetic Polymers and Molecular Imprinted Polymers (MIPs)... 

A class II aldolase-mimicking synthetic polymer was prepared by the molecular imprinting of a complex of cobalt (II) ion and either (lS,3S,4S)-3-benzoyl-l,7,7-trimethylbicyclo[2.2.1] heptan-2-one (4a) or (lR,3R,4R)-3-benzoyl-l,7,7-trimethylbicyclo[2.2.1]heptan-2-one (4b)... 

Siemann M, Andersson LI, Mosbach K. Separation and detection of maciolide antibiotics by HPLC using macrolide-imprinted synthetic polymers as stationary phases. J Antibiot 1997 50 89-91. 

Stereoselective catalysis using biocatalysts (e.g. enzymes) and also of rationally designed small chiral molecules, deals essentially with the same principle the spatial and selective docking of guest molecules to a chiral host molecule to form complementary interactions to form reversible transient molecule associates (see the specific sections in this volume). The enantiomeric excess of a certain reaction and hence the result will be determined by the degree of chiral discrimination. Along the same theoretical lines the concepts of protein (enzyme, antibody, etc.) mimicks via imprinted" synthetic polymers should be mentioned and will be discussed further. 

Figure 12. Generalized scheme for the formation of a polymeric network with imprinted cavities base d on the chemical and special characteristics of the template (T) the natural polymerlike antibody-type proteins recognize xenobiotics, a fully synthetic polymer may recognize the preentrapped and afterwards washed out template (T) molecule.

Mosbach and collaborators, in 2001, described an innovative approach to drug discovery using polymers imprinted with a biologically active template [31]. The approach, called anti-idiotypic for the similarity with anti-idiotypic antibodies in the immune-response, can be used to create synthetic receptors able to generate inhibitors or receptor antagonists by exploiting the complementarity with the cavity. The imprinted cavity promotes preferentially the formation of compounds with high affinity, which can later be evaluated for the inhibitory activity and the more active selected for further analysis. 

The most popular and commonly used chiral stationary phases (CSPs) are polysaccharides, cyclodextrins, macrocyclic glycopeptide antibiotics, Pirkle types, proteins, ligand exchangers, and crown ether based. The art of the chiral resolution on these CSPs has been discussed in detail in Chapters 2-8, respectively. Apart from these CSPs, the chiral resolutions of some racemic compounds have also been reported on other CSPs containing different chiral molecules and polymers. These other types of CSP are based on the use of chiral molecules such as alkaloids, amides, amines, acids, and synthetic polymers. These CSPs have proved to be very useful for the chiral resolutions due to some specific requirements. Moreover, the chiral resolution can be predicted on the CSPs obtained by the molecular imprinted techniques. The chiral resolution on these miscellaneous CSPs using liquid chromatography is discussed in this chapter. 

In spite of the development of more successful and reliable CSPs (Chaps. 2-8), these miscellaneous types of CSP have their role in the field of the chiral resolution also. The importance of these CSPs ties in the fact that they are readily available, inexpensive, and economic. Moreover, these CSPs can be used for some specific chiral resolution purpose. For example, the CSP based on the poly(triphenylmethyl methacrylate) polymer can be used for the chiral resolution of the racemic compounds which do not have any functional group. The CSPs based on the synthetic polymers are, generally, inert and, therefore, can be used with a variety of mobile phases. The development of CSPs based on the molecularly imprinted technique has resulted in various successful chiral resolutions. The importance and application of these imprinted CSPs lies in the fact that the chiral resolution can be predicted on these CSPs and, hence, the experimental conditions can be designed easily without greater efforts. Because of the ease of preparation and the inexpensive nature of these CSPs, they may be useful and effective CSPs for chiral resolution. Briefly, the future of these types of CSP, especially synthetic polymers and polymers prepared by the molecularly imprinted technique, is very bright and will increase in importance in the near future. 

MATSUI J, MIYOSHIY, doblhoff-dier o and TAKEUCHIT (1995), A molecularly imprinted synthetic polymer receptor selective for atrazine , Anal Chem,... 

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