Automated organic synthesizers

The first step in the chemical synthesis is to investigate the scope and limitations of the synthetic reactions [32, 40], since different clusters of compounds, or even compounds within a cluster, may require different experimental settings. Even with automated solid state syntheses using polymer beads as carriers of compounds, the synthetic steps need to be optimised so that reasonable yields are obtained for all compounds in the library. Otherwise unbalanced test data will result, with subsequent loss of information. Such optimisation is easy to accomplish with few compounds. Recently, robots that optimise organic syntheses on the basis of statistical... 

Bicknell et al. (161) has recently reported the successful transfer onto SP of a modified version of the Tsuge reaction (162) to produce a 96-member discrete hbrary L5 of tricyclic compounds by means of a commercially available automated SP multiple organic synthesizer (163). In this synthetic adaptation, the Tsuge reaction, that is, cycloaddition of pyridinium methilides with olefinic dipolarophiles, as shown in... 

Unlike solid-phase organic synthesizers, automated synthesizers for peptide synthesis are commercially available (Advanced ChemTech, Protein Technologies, to name just two old players in this field). The automated solid-phase synthesis of peptides was reviewed in 2002,and then again with aspects of peptidomimetic development. " Since the landscape changes frequently, the latest information can always be obtained on the Internet. 

This issue highlights the characterization difference between parallel synthesis and combinatorial synthesis. Parallel synthesis is automated traditional organic chemistry. Each compound is made in a separate reactor, purified and characterized. There is no excuse for not fully characterizing compounds made by parallel synthesis. Jonathan Ellman s laboratory at UC Berkeley has been a pioneering academic center for solid-phase chemistry development. His philosophy is to synthesize libraries of discrete compounds in a spatially separate fashion, rather than libraries of compound mixtures, to allow for rigorous analytical characterization [48,49],... 

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