10.1016/S0960-894X(97)00278-3
The research focuses on the synthesis of novel non-nucleosidic phosphoramidites and controlled pore glass (CPG) supports, which are based on a cyclohexyl-4-amino-1,1-dimethanol backbone. The purpose of this study was to develop a series of reagents that could be used to label oligonucleotides with biotin and fluorescein at various positions, including the 5'-, 3'-, and internal sites. The researchers aimed to improve the efficiency of synthesis and mimic the stereochemical properties of the natural polynucleotide backbone, while also keeping the reporter groups away from the oligonucleotide chain to enhance hybridization efficiency. The key chemicals used in the process included 3-cyclohexene-1,1-dimethanol, benzoyl chloride, sodium borohydride, BF3-Et2O, hydroxylamine-O-sulfonic acid, biotin-N-hydroxysuccinimide ester (biotin-NHSu), fluorescein-NHSu, and various other reagents for the protection, deprotection, and coupling steps. The conclusions of the research were that these novel biotin, fluorescein, and amino labeled phosphoramidites and CPG supports could be used advantageously for the introduction of multiple reporter groups onto oligonucleotides in a cost-effective and efficient manner, retaining the natural 3-carbon atom internucleotide phosphate distance in DNA/RNA, which does not affect the hybridization and annealing properties of the duplex.