Antibiotics, chirality

Aboul-Enein, H.Y and Ali, I., Optimization strategies for HPLC enantioseparation of racemic drugs using polysaccharides and macrocyclic antibiotic chiral stationary phases, II Farmaco, 57, 513, 2002. 

Aboul-Enein, H.Y. and Serignese, V., Quantitative determination of clenbuterol enantiomers in human plasma by high-performance liquid chromatography using the macrocyclic antibiotic chiral stationary phase teicoplanin, Biomed. Chromatogr., 13, 520, 1999. 

Based on the theory, the separation of enantiomers requires a chiral additive to the CE separation buffer, while diastereomers can also be separated without the chiral selector. The majority of chiral CE separations are based on simple or chemically modified cyclodextrins. However, also other additives such as chiral crown ethers, linear oligo- and polysaccharides, macrocyclic antibiotics, chiral calixarenes, chiral ion-pairing agents, and chiral surfactants can be used. Eew non-chiral separation examples for the separation of diastereomers can be found. 

Aboul-Enein, H. and Ali, I. (2002) Optimization Strategies for HPLC Enantioseparation of Racemic Drugs Using Polysaccharides and Macrocyclic Glycopeptide Antibiotic Chiral Stationary Phases, Farmaco 57, 513-529. 

Pharmaceuticals and fine chemicals, where its product portfolio covers a wide variety of specialties including antibiotics, chiral intermediates, and recombinant proteins. 

Despite these evident drawbacks, a broad variety of SOs have been used in CMPA-based enantiomer separations, including cyclodextrins, proteins, macro-cyclic antibiotics, chiral ion-pairing agents, amino acids in combination with transition metal salts, and crown ethers. Recent application for the separation of pharmaceutically relevant chiral compounds utilized P-cyclodextrins [46-48] charged cyclodextrins [49, 50], macrocyclic antibiotics [51, 52] and chiral ion-pairing agents [53, 54]. A more detailed discussion of CMPA-based enantiomer separation is beyond the scope of this chapter. The interested reader is referred to dedicated reviews [55, 56]. 

The reactions of enolates with aldehydes (aldol reactions) or with imines have been widely developed since the 1970s. Asymmetric aldol-type reactions are very important in the multistep synthesis of complex molecules such as ionophores or p-lactam antibiotics. Chirality has been introduced either on the substituents of boron, on the metal ligands or on the carbon skeleton of the enolate. Aldol reactions are usually run at low temperatures, and when metal enolates are used, the reactions are sometimes easily reversible [160, 209],... 

CARBON-13 NMR SPECTRA SMALL PEPTIDES DIHYDROFOLATE REDUCTASE ANTIBIOTICS CHIRAL RESOLUTION DRUG METABOLISM... 

Double bond, 14, 38-40, 170-172 Double helix, 1094—1096. See also Deoxyribonucleic acid Drugs. See also AIDS Antibiotics chiral, 273 generic names of, 63 Dyes, 896-897... 

Fine and speciality chemicals, for example, antibiotics, chiral intermediates for pharmaceuticals, agrochemicals, sugars, and derivatives such as sorbitol, specialty enzymes, vitamins, dyes, fragrances, cosmetics, and polysaccharides. 

Medvedovici A, Sandra P, Tortblo L, David F (1997) Chiral packed column subciitical fluid chromatography on polysaccharide and macrocycUc antibiotic chiral stationary phases. 1 Chromatogr A 785 159-171... 

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