Abstract: The invention relates to the development and optimization of PCR and RT-PCR systems used to detect nucleic acids, including the diagnosis of genetic, viral, and other diseases. The essence of the proposed method is that neutral derivatives of oligonucleotides, namely phosphoryl guanidines containing one or more phosphate groups in which guanidine or substituted guanidine residue is introduced on the phosphorus atom, are used as primers for the template-based amplification, including polymerase chain reaction (PCR) and PCR combined with reverse transcription (RT-PCR). The invention allows to obtain more reliable, specific and selective results in the process of PCR, in particular, to increase the sensitivity of PCR by reducing the yield of by-products of DNA amplification and/or to control the yield of the PCR product, including intentionally suppressing, by using different combinations of the location and number of modified phosphate groups in the oligonucleotide primers.

Abstract: The present invention is directed to modified oligonucleotides having the following Formula (I) wherein one or more of phosphate groups are substituted at phosphorus, and methods for their synthesis. The modified oligonucleotides are useful for diagnostic applications involving sequence specific recognition of a nucleic acid and for use in a method of medical treatment.

Abstract: The present invention is directed to modified oligonucleotides having the following Formula (I) wherein one or more of phosphate groups are substituted at phosphorus, and methods for their synthesis. The modified oligonucleotides are useful for diagnostic applications involving sequence specific recognition of a nucleic acid and for use in a method of medical treatment.

Abstract: The present invention is directed to modified oligonucleotides having the following Formula (I) wherein one or more of phosphate groups are substituted at phosphorus, and methods for their synthesis. The modified oligonucleotides are useful for diagnostic applications involving sequence specific recognition of a nucleic acid and for use in a method of medical treatment.