Abstract

A method for synthesis of oligonucleotide analogs having dithiophosphate internucleosidic linkages is described. Monohalohydrocarbylthiophosphoramidites are utilized to prepare nucleoside thiophosphoramidite intermediates which are activated for nucleoside coupling with tetrazole catalysts. Sulfur oxidation and dehydrocarbylation of the coupled thiophosphite intermediates provide oligonucleotide analogs having achiral dithiophosphate internucleosidic linkages.

Other References

• "Deoxynucleoside Phosphoramidites--A New Class Of Key Intermediates For Deoxypolynucleotide Synthesis", Tetrahedron Letters, vol. 22, No. 20, pp. 1859-1862, 1981, Beaucage et al
• "An Investigation Of Several Deoxynucleoside Phosphoramidites Useful For Synthesizing Deoxyolignucleotides", McBride et al., Tetrahedron Letters, vol. 24, No. 3, pp. 245-248, 1983
• "Synthesis Of Dinucleoside Phosphorodithioates Via Thioamidites", Brill, et al., Tetrahedron Letters, vol. 29, No. 43 pp. 5517-5520, 1988
• "Synthesis Of Oligodeoxynucletides Containing Specific Methylphosphonothioate and Dithioate Moieties", Brill, et al., Aug. 8-12, 1988
• "Preparation Of A Deoxynucleside Thiophosphoramidite Intermediate In The Synthesis Of Nucleoside Phosphorodithioates", Faraschtschi & Gorenstein, Tetrahedron Letters, vol. 29, No. 52, pp. 6843-6846, 1988
• "Synthesis Of Oligodeoxynucleoside Phosphorodithioates Via Thioamidites", Brill, et al., J. Amer. Chem. Soc., 1989, vol. 111, pp. 2321-2322
• Chemical Abstracts No. 107:198467b, Al'fonsov et al. Zh. Obshch. Khim, 56(8), 1697-1699 (1986)
• Chemical Abstracts No. 96:85bb8d, Sinyashin et al. Zh. Obshch. Khim. 51(11), 2410-2413, (1981