|
Overview of Phosphate Bond Modifications
- PHOSPHOROTHIOATES (pure or mixed)
 | Modification structure | Phosphorothioates contain replacement of one oxygen in the phosphate bond by sulphur. The replacement of oxygen by sulphur increases oligonucleotide resistance against nucleases. Pure phosphorothioates: The replacement is done in all phosphate bonds in the chain Mixed phoshorothioates: The replacement is done only in selected phosphate bonds.
| | Application | Methylphosphonates are used especially for antisense applications. | | Recommended purification type: | OPC | | Term of delivery | B | | Price | Calculated according to the following table. |
|
| Coefficients to calculate the phosphorothioate prices: | | 40 nmol | 200 nmol | 1 µmol | 10 µmol | | 2,25 | 1,9 | 1,4 | 1,25 |
|
- METHYLPHOSPHONATES (pure or mixed)
 | Modification structure | Methylphosphates have one of the oxygen atoms of the phosphate bond replaced by the methyl group. They are stable against nucleases on the order of several days; they do not activate Rnase H. Pure methylphosphonates: The replacement is done in all phosphate bonds Mixed methylphosphonates: The replacement is done only in selected phosphate bonds
| | Application | Methylphosphonates are used especially for antisense applications. | | Recommended purification type: | OPC | | Term of delivery | X | | Price | Individual calculation is necessary (according to representation of individual bases) |
|
- H-PHOSPHONATES (pure or mixed)
 | Modification structure | One of oxygen atoms on the phosphate bond is replaced by hydrogen. Pure H-phosphonates: The replacement is done in all phosphate bonds Mixed H-phosphonates: The replacement is done only in selected phosphate bonds | | Application | H-phosphonates are used especially as intermediate products in preparation of other modifications of the phosphate bond (amidates, triesters, radioactively labelled phosphorothioates etc.) | | Recommended purification type: | OPC | | Term of delivery | X | | Price | Individual calculation is necessary (according to representation of individual bases) |
|
|
