Solid supports controlled pore glass

Synthesis (i) a hydrophobic polymer, terminally modified with a carboxylic acid moiety, was mixed with a coupling agent and reacted with a 50-amino-modified oligonucleotide on solid support (controlled pore glass, CPG) (ii) deprotection and cleavage of the resulting DNA polymer conjugate from solid support (iii) dialysis of cleaved DPA into deionized water to form a mixture... 

CPG = Controlled Pore Glass (solid support) 1 and 2 (Bj, B2, B3, B4), commercially available... 

Even controlled-pore glass (CPG) could be successfully employed as solid support with (9-glycosyl trichloroacetimidates as glycosyl donors. Thus, limitations of solvents and reaction temperatures in the glycosylation step, as experienced with the Merrifield resin, are restricted to those observed in solution-phase synthesis. Therefore, regio- and stereocontrol of the glycosylation reactions should be available from well-established solution-phase methodologies. 

For the automated solid-phase synthesis of oligonucleotides, however, silica was found to be the support of choice [192-197]. Silica with large pore size (25-300 nm), so-called controlled pore glass (CPG), is generally used for this purpose. The main advantages of CPG, as compared with silica gel, are its more regular particle size and shape, and greater mechanical stability. 

The above list of solid supports is by no means exhaustive. Many others have been proposed and evaluated for use in peptide synthesis, including polypropylene membranes, cotton, controlled-pore glass beads, polyethylene sheets, and others. 

The biocatalyzed phenylacetyl removal can be carried out using both solubilized or immobilized substrates1771. The latter methodology has been developed using controlled pore glass (CPG) as a solid support (Fig. 18-7). 

An oligonucleotide bearing a 3 -phosphoryltyrosine residue has been synthesised from the modified tentagel or controlled pore glass solid support (202). The hydroxyl group of tyrosine was protected with a levulinoyl group which could be removed with sodium borohydride. 

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