Oligomer library

Solubility. Anecdotal evidence from several sources suggests that this is a particular concern. However, it is difficult to predict a priori, particularly in instances where oligomer libraries (rather than simple binary or A/B type libraries) are to be generated. 

Phenylacetylene chemistry allows construction of shape-persistent molecular architectures through structural control and monomer diversity.27 Combination of this method with solid-phase techniques enhances the rate at which compounds can be made, especially because automation is possible. Oligomer libraries may also be accessible using this type of chemistry. 

Figure 2 The structure of a tripeptide and the corresponding monomer for solid-phase synthesis, contrasted with trimers and monomers for three other oligomer libraries prepared from bifunctional monomers...

Figure 7.13. Molecular structures of N-Fmoc-protected oxazole (14) and thiazole (15) amino acids used as monomers of oligomer libraries.

As a consequence of the progress and success of diverse oligomer libraries, experts in combinatorial synthetic oligomers, glycopeptide and oligosaccharide libraries, RNA-and DNA-aptamers have each contributed their news in these fields, while novel experimental examples of the use of templates in combinatorial chemistry for the solid-phase synthesis of multiple core structure libraries provide some insight to praxis-relevant work. 

Contrary to the Berkeley and Affymax report, the diversomer paper by Hobbs DeWitt et al. placed no emphasis on the preparation of an oligomer library but focussed entirely on the generation of a library of diverse, albeit related, organic compounds called diversomers . [8] An important reason for the creation of these libraries was to discover lead... 

The major components are series of homologous trimers, tetramers, and pentamers of the three acids 44-46, along with smaller quantities of dimers, hexamers, and heptamers. Furthermore, the secretion contains several isomers of each oligomer, furnishing a combinatorial library of several hundred macro-cyclic polyamines [51, 52]. Using repeated preparative HPLC fractionation, the most abundant trimeric, tetrameric and pentameric earliest-eluting compounds were isolated. One and two-dimensional H NMR spectroscopic analyses showed that these molecules were the symmetric macrocyclic lactones 48, 49, and 50 (m, n, o, p, q=7) derived from three, four or five units, respectively, of acid 46. Moreover, using preparative HPLC and NMR methods, various amide isomers, such as 53,54, and 55 (Fig. 9) were also isolated and characterized [51,52]. 

Figure 3.25 Racemic dynamic combinatorial library targeting (-)-adenosine. Left Racemic porline containing dipeptide library building block. Middle Various enantiomeric oligomers formed through reversible hydrazone exchange. Right The SS enantiomer selected upon equilibration with (-)-adenosine.

Historically, the first major libraries were oligomers of naturally occurring monomers. A good example would be a library of all possible tripeptides. Using the twenty naturally... 

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