Solid oligonucleotide synthesis

The protected nucleoside-3-phosphoramidite monomer units such as 671 are used in the solid-phase oligonucleotide synthesis. In the 60mer synthesis, 104 allylic protective groups are removed in almost 100% overall yield by the single Pd-catalyze reaction with formic acid and BuNH2[432], N,(9-protection of uridine derivatives was carried out under pha.se-transfer conditions[433]. 

Synthetic organic polymers, which are used as polymeric supports for chromatography, as catalysts, as solid-phase supports for peptide and oligonucleotide synthesis, and for diagnosis, are based mainly on polystyrene, polystyrene-divinylbenzene, polyacrylamide, polymethacrylates, and polyvinyl alcohols. A conventional suspension of polymerization is usually used to produce these organic polymeric supports, especially in large-scale industrial production. 

One widely used method involving protected compounds is solid-phase synthesis (polymer-supponed reagents). This method has the advantage of requiring only a simple workup by filtration such as in automated syntheses, especially of polypeptides, oligonucleotides, and oligosaccharides. 

The disadvantage of this method is that the dichloridites and monochloridites are sensitive to water and thus could not be used readily in automated oligonucleotide synthesis. This problem was overcome by Beaucage and Caruthers, who developed the phosphoramidite approach. In this method, derivatives of the form R 0P(NR2)2 react with one equivalent of an alcohol (catalyzed by species such as l//-tetrazole) to form diesters, R OP(OR")NR2, which usually are stable, easily handled solids. These phosphoroamidites are easily converted to phosphite triesters by reaction with a second alcohol (catalyzed by l//-tetrazole). Here, again, oxidation of the phosphite triester with aqueous iodine affords the phosphate triester. Over the years, numerous protective groups and amines have been examined for use in this approach. Much of the work has been reviewed. ... 

Synthetic oligonucleotides are very important tools in the study and manipulation of DNA, including such techniques as site-directed mutagenesis and DNA amplification by the polymerase chain reaction. The techniques for chemical synthesis of oligonucleotides are highly developed. Very efficient automated methodologies based on solid phase synthesis are used extensively in fields that depend on the availability of defined DNA sequences.52... 

Silica or porous glass is usually used as the solid phase in oligonucleotide synthesis. The support is functionalized through an amino group attached to the silica surface. There is a secondary linkage through a succinate ester to the terminal 3 -OH group. 

Over the past decade the techniques of combinatorial synthesis have received much attention. Solid phase synthesis of polypeptides and oligonucleotides are especially adaptable to combinatorial synthesis, but the method is not limited to these fields. The goal of combinatorial synthesis is to prepare a large number of related... 

Nucleotides and nucleic acids are critical tools in the areas of gene expression, therapeutics, and diagnostics. However, there are certain challenges associated with their large-scale purification and subsequent characterization. While solid-state oligonucleotide synthesis is relatively simple and can be totally automated, intra- and intermolecular associations may occur involving shorter sequences that may hybridize with the desired full length... 

William Fraser was born in Hamilton. He studied at the other of the two local universities, Strathclyde, where he obtained a first class B.Sc. honors degree in 1986 and Ph.D. in 1989 under the direction of Professor Colin J. Suckling and Professor Hamish C. S. Wood. He was awarded a Royal Society European Exchange Postdoctoral Fellowship and worked in the laboratories of Professor Albert Eschenmoser at the ETH, Zurich. In 1991, he took up his present position as lecturer in medicinal chemistry at Aston University, Birmingham. His scientific interests include nucleoside and nucleic acid chemistry, solid-supported, synthesis, and study of base-modified antigene oligonucleotides targeted to DNA. 

R Arshady, E Atherton, MJ Gait, RC Sheppard. An easily prepared polymer support for solid phase peptide and oligonucleotide synthesis. Preparation of substance P and a nonadeoxyribonucleotide. J Chem Soc Chem Commun 423, 1979. 

With the development of appropriate cartridges and proper chemistry that would allow the synthesis of the molecule on the disk and than the use of the same disk directly for affinity chromatography by placing it in a chromatographic cartridge, it is reasonable to expect that SMC will become a very efficient tool in the solid phase synthesis of peptides, oligonucleotides, and similar molecules. 

The ability to synthesize chemically short sequences of single-stranded DNA (oligonucleotides) is an essential part of many aspects of genetic engineering. The method most frequently employed is that of solid-phase synthesis, where the basic philosophy is the same as that in solid-phase peptide synthesis (see Section 13.6.3). In other words, the growing nucleic acid is attached to a suitable solid support, protected nucleotides are supplied in the appropriate sequence, and each addition is followed by repeated coupling and deprotection cycles. 

SCHEME 34. synthesis of protected phosphoramidites suitable for solid-phase oligonucleotide synthesis. 

Scheme 13.55. Automated Solid-Phase Synthesis at Oligonucleotides ...

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