Solid phase synthesis SPS

Two general methods are used to build a library of compounds by the general techniques of combinatorial chemistry solid-phase synthesis (SPS) and solution-phase synthesis. 

Conventional liquid phase synthesis suffers from the limitation that each product or intermediate has to be separated from the other components of the reaction mixture. An elegant answer to this problem is to use a solid phase synthesis (SPS) approach. In such an approach the compounds are synthesized on a solid support and simple washing steps replace the laborious work up and isolation procedures. At the end of the synthesis the product is released from the solid support. The SPS of oligomers of amino acids or nucleotides is well estabilished and task chemists are facing now is the development of SPS routes for small organic molecules. 

Solid-phase synthesis (SPS) is limited by a shortage of simple and rapid techniques for reaction monitoring, specifically for functional group transformations. The traditional preparation and subsequent analysis (HPLC,... 

Polymer-supported Synthetic Methods - Solid-phase Synthesis (SPS) and Polymer-assisted Solution-phase (PASP) Synthesis... 

Fig. B.14.1. Classical solid-phase synthesis (SPS) and polymer-assisted solution phase (PASP). In SPS (I) products are constructed step-wise, covalently attached to an insoluble polymer support. PASP...

Since the beginning, combinatorial chemistry has strongly depended on the techniques of solid-phase synthesis (SPS). For this reason a detailed presentation of solid-phase (SP) chemistry in which the differences compared to classical organic chemistry in solution are highlighted appears at the beginning of this book. 

Solid-phase synthesis (SPS) of peptides containing at their C-termini the usual carboxylic acid or carboxamide functionalities is a well-established process the peptide is traditionally attached to the resin through the a-carboxyl group of the C-terminal residue, and synthesis proceeds in the C A direction (1,2). However, synthetic peptides containing modifications at the C-termini are often desired because of their potential therapeutic properties and/or synthetic significance as intermediates in peptide and protein chemistry. Therefore, effective solid-phase methods are needed for the preparation of these peptide targets (3). The present chapter describes backbone amide linker (BAL) strategies (4)... 

The process of solid-phase synthesis (SPS) involves linking the snbstrate to the resin, carrying out various reactions, washing away by-products, and finally cleaving the prodnct from the support with minimal impurities. The polymer-bound intermediates may simply be filtered off and washed after each stage or, more conveniently, by using a special flask containing a sinter, controlled by a stopcock, at the base. 

Figure 14.7 Solid phase synthesis (SPS) using immobilized carbamates and carbazates on Wang resin.

Carbodiimides were the coupling reagents most commonly used in solid-phase synthesis (SPS) until about 1985 (Fig. 3) [13-15]. For conducting SPS involving an intermediate treatment with trifluoroacetic acid (TFA) [e.g., solid-phase peptide synthesis (SPPS) by the rert-butoxycarbonyl (Boc)/... 

In solid phase synthesis (SPS) of biopolymers, the peptide/nucleotide/glycoside chain is assembled in the nsnal manner (conventional approach) from the C-/3 -/NR-end. The first monomer unit of the biopolymer to be synthesized is connected via its car-boxyl/hydroxyl/hydroxyl gronp to an insoluble polymer. A necessary prerequisite is that anchoring groups (linkers) are introdnced into the polymeric material (step 1). The first protected monomer is then reacted with the functional gronp of the linker (step 2). The... 

Solid-phase reactions play an important role in parallel synthesis and combinatorial chemistry, particularly in the area of medicinal chemistry, where their potential has emerged as a result of the possibility of automation. Considerable attention has been focused on adapting and exploiting the advantages of solid-phase synthesis (SPS) to produce libraries of such organic compounds. In this context, transition metal-pro-... 

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