Abstract: This invention is related to nucleic acid chemistry and describes novel 1,2-dithiolane functionalized nucleoside phosphoramidites (1, Chart 1) and corresponding solid supports (2, Chart 1). In addition to these derivatives, 1,2-dithiolane moiety can also be functionalized to at the various positions of the nucleobase and sugar part as shown in Schemes 1 to 8. The nucleosides of our invention carry a primary hydroxyl for DMTr (4,4?-dimethoxytrityl) function for chain elongation. Furthermore, the phosphoramidite function is attached at the 3?-hydroxyl of the nucleoside. This allows oligonucleotide chain extension under standard DNA and RNA synthesis chemistry conditions and techniques, thus leading to high quality oligonucleotides. These derivatives are useful for introduction of reactive thiol groups either at 3?- or 5?-end of the oligonucleotides on the solid supports such as gold, silver and quantum dots.

Abstract: This invention is related to nucleic acid chemistry and describes novel 1,2-dithiolane functionalized nucleoside phosphoramidites (1, Chart 1) and corresponding solid supports (2, Chart 1). In addition to these derivatives, 1,2-dithiolane moiety can also be functionalized to at the various positions of the nucleobase and sugar part as shown in Schemes 1 to 8. The nucleosides of our invention carry a primary hydroxyl for DMTr (4,4?-dimethoxytrityl) function for chain elongation. Furthermore, the phosphoramidite function is attached at the 3?-hydroxyl of the nucleoside. This allows oligonucleotide chain extension under standard DNA and RNA synthesis chemistry conditions and techniques, thus leading to high quality oligonucleotides. These derivatives are useful for introduction of reactive thiol groups either at 3?- or 5?-end of the oligonucleotides on the solid supports such as gold, silver and quantum dots.

Abstract: The 5? and 3?-thiol modified oligonucleotides are attractive tools with a vast number of potential applications in the field of nucleic acid chemistry. There is a strong interest in developing new disulfide compounds or to optimize synthesis of existing disulfide modifiers, which are efficient in generating the 3?- or 5?-end reactive thiol group. Various synthetic protocols have been employed to synthesize pure 3-((3-(bis(4-dimethoxytrityl)propyl)di-sulfanyl)propyl 2-cyanoethyl diisopropylphosphoramidite (compound 2) starting from 3-(dimethoxytrityl)propyl)disulfanyl)pro-pan-1-ol, (compound 1). Herein, we describe an efficient, reproducible synthetic and purification protocol for target compound 2 from the compound 1. It is noteworthy that our reaction conditions were reproducible even at multi-gram scale (27 g) with a purity level as achieved in a small scale.